Minimize Starlink

Starlink Satellite Constellation of SpaceX

Spacecraft    Launches    Mission Status     References 

Starlink is a satellite constellation development project underway by SpaceX, to develop a low-cost, high-performance satellite bus and requisite customer ground transceivers to implement a new spaceborne Internet communication system.

SpaceX has said it will offer speeds of up to 1 Gbit/s, with latencies between 25 ms and 35 ms. Those latencies would make SpaceX's service comparable to cable and fiber, while existing satellite broadband services have latencies of 600 ms or more, according to FCC measurements.

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Figure 1: Starlink constellation logo (image credit: SpaceX)

Some background: In November 2016, SpaceX filed an application with the FCC (Federal Communications Commission) for a license to operate a constellation of 4425 non-geostationary satellites (NGS) in orbits ranging from 1100 and 1300 km. However, when they issued their regulatory filings in 2017, the plan called for the deployment of nearly 12,000 satellites in Low Earth Orbit (LEO). 1)

However, competition from other satellite internet providers forced SpaceX to expedite their plans. By the Fall of 2018, the company announced a new plan to deploy their first batch of 1600 satellites to a lower altitude at 550 km. The development team also introduced a simplified design so that the first batch would be ready to go no later than the June of 2019.

Rather than broadcasting in two bands (“Ku” and “Ka”), the simplified design of the first batch will broadcast only in the “Ku” band. At present, SpaceX hopes to launch 2200 satellites in the next five years, which will act as a sort of prototype while the company develops an improved design for full-scale production.

Eventually, this will result in a constellation that offers the kinds of performance outlined in the company’s original plan. This presents numerous challenges, not the least of which is the fact that they will need to conduct launches every month for the next five years, averaging 44 satellites per launch.

Second, there’s the matter of attrition, as satellites will begin to deorbit after a few years and SpaceX will need to replace them regularly in order to maintain its constellation. In fact, Hugh Lewis – the UK Space Agency’s representative on the Inter-Agency Space Debris Coordination Committee – recently stated that in order to maintain a constellation of just 4425 satellites, SpaceX will have to launch that many every five years.

However, SpaceX intends to use this to their advantage by gradually replacing inactive satellites with ones that offer superior performance. In this way, the constellation will gradually be upgraded with the addition of heavier satellites that are capable of transmitting more information, and which are placed in longer-lasting, higher orbits.

SpaceX will also need a lot of production space if they are going to meet even the more modestly-sized constellation of 4425. While the company has commenced converting one of their Starlink buildings into a prototype production facility that will assemble the first few dozen satellites, this is merely a fraction of what they will need in the long run.

Starlink is also going to be seeing competition in the coming years thanks to companies like OneWeb and Telesat, which plans to create smaller constellations that will offer service by 2021. Tech giants like Amazon and Samsung have also announced plans to deploy their own constellations, which would consist of 3,236 to 4600 broadband satellites, respectively.


Spacecraft

Designed and built upon the heritage of Dragon, each spacecraft is equipped with a Startracker navigation system that allows SpaceX to point the satellites with precision. Importantly, Starlink satellites are capable of tracking on-orbit debris and autonomously avoiding collision. Additionally, 95 percent of all components of this design will quickly burn in Earth’s atmosphere at the end of each satellite’s lifecycle—exceeding all current safety standards—with future iterative designs moving to complete disintegration. This mission will push the operational capabilities of the satellites to the limit. SpaceX expects to encounter issues along the way, but the lessons learned here are key to developing an affordable and reliable broadband service in the future (Ref. 48).

Some spacecraft parameters: 2)

• Flat-panel design with multiple high-throughput antennas and a single solar array

• Spacecraft mass: 227 kg

• Hall-effect thrusters using krypton as the reaction mass, for position adjustment on orbit, altitude maintenance and deorbit

• Star tracker navigation system for precision pointing

• Able to use Department of Defense provided debris data to autonomously avoid collision 3)

• 95 percent of "all components of this design will quickly burn in Earth’s atmosphere at the end of each satellite’s lifecycle"

The 60 Starlink V1.0 satellites, launched on 11 November 2019, have the additional following characteristics:

• 100% of "all components of this design will quickly burn in Earth's atmosphere at the end of each satellite's lifecycle."

• Ka-band added

• Spacecraft mass of 260 kg

• Albedo reduced.

The satellites are stacked for launch without the need for a dispenser. As a propulsion system for orbit adjustment and maintenance as well as deorbiting, they use krypton-fueled Hall thrusters. The startracker navigation system is based on the heritage of Dragon. The satellites are designed autonomously avoid collisions based on uplinked tracking data. At the end of life, the Starlink satellites are to be actively deorbited, leading to reentry.

Orbit: Circular orbit with an altitude of 550 km. The Starlink spacecraft constellation will be spread into 24 orbital planes with an inclination of 53º.




Development status of the Starlink constellation

• April 15, 2021: SpaceX has added more than $300 million to a fundraising round announced earlier this year to support continued work on its Starship launch system and Starlink satellite constellation. 4)

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Figure 2: SpaceX President Gwynne Shotwell said April 14 that she expects the company’s Starship vehicle to be carrying “large numbers of people” to space, including to the moon, within five years (image credit: SpaceNews/Brian Berger)

- In an amended filing with the U.S. Securities and Exchange Commission April 14, the company revised a filing in February that disclosed raising $850 million. The company says it has now raised $1.164 billion.

- The company didn’t provide details on the source of the additional $314 million. The filing stated that 99 investors participated in the round, compared to 69 in its February filing about the round. The filing also didn’t disclose terms of the financing, although reports in February indicated that new round valued SpaceX at $74 billion, a significant increase over earlier round.

- SpaceX raised $1.9 billion in its previous funding round in August 2020. It has raised more than $6 billion in equity to date.

- Much of that investment has gone to support two high-profile, and high-expense, projects SpaceX is pursuing. One is the Starlink constellation of broadband internet satellites the company is currently deploying, with about 1,350 satellites currently operational.

- In an April 14 talk at the SpaceTech conference by the Massachusetts Institute of Technology’s Department of Aeronautics and Astronautics, Gwynne Shotwell, president and chief operating officer of SpaceX, reiterated comments she made earlier this month that the company will soon have enough satellites in orbit to provide global coverage.

- “With Starlink, we anticipate having full global connectivity, consistent global connectivity, a few months after our 28th launch,” she said, a milestone she anticipated reaching “late this year.” An April 7 launch was the 23rd of the company’s v1.0 Starlink satellites. “We will continue to add capacity with additional satellites after that. We will continue to improve our technology, and basically get more beams on the ground.”

- Among those technology improvements is the incorporation of laser intersatellite links. Shotwell said the company has already tested two generations of that technology on some of its satellites. “The first ones that we flew were very expensive. The second round of technology that we flew was less expensive,” she said.

- A third generation of laser intersatellite links will start flying “in the next few months,” she said. She didn’t elaborate on those plans, but it’s likely those will be included on satellite the company is preparing to launch to polar orbits. The new technology, she said, will be able to operate over longer distances and provide high bandwidth, while being “much less expensive” than earlier versions.

- SpaceX’s other capital-intensive project is its Starship launch system. The company has flown, and destroyed, four Starship prototypes on suborbital test flights in recent months, most recently March 30. A new Starship prototype, SN15, recently arrived on the launch pad at SpaceX’s Boca Chica, Texas, test site for a flight test that could happen as soon as late this month.

- “Starship is an amazing machine. I could not be more excited about a vehicle than I am about Starship,” Shotwell. “That is the vehicle that will take people in great numbers to the moon, to Mars.”

- Despite a test campaign that has so far been filled with vehicle explosions, she remained optimistic that the vehicle will be ready to fly people within several years. “I believe we will be flying large numbers of people on Starship in five years,” she said, including point-to-point transportation between two locations on Earth, a concept SpaceX first discussed in 2017.

- Asked by Dava Newman, an MIT professor and former NASA deputy administrator, if that meant SpaceX would be ready to send people to Mars by 2030 to 2035, Shotwell offered a more aggressive schedule. “We’re shooting for before 2030. It might end up taking that long, but I hope not,” Shotwell said.

- That timeline, she said, was based on the experience she expected the company to build up flying people on point-to-point and lunar Starship missions. “You’re flying enough where you hopefully have enough knowledge of the system and knowledge of risk that you can definitely start the journey to Mars within the next five years.”

- “I recognize,” she added, “we never make our timelines, so they’re aspirational. But you have to aim high.”

• March 18, 2021: NASA and SpaceX have signed a joint agreement to formalize both parties’ strong interest in the sharing of information to maintain and improve space safety. This agreement enables a deeper level of coordination, cooperation, and data sharing, and defines the arrangement, responsibilities, and procedures for flight safety coordination. The focus of the agreement is on conjunction avoidance and launch collision avoidance between NASA spacecraft and the large constellation of SpaceX Starlink satellites, as well as related rideshare missions. A conjunction is defined as a close approach between two objects in space, usually at very high speed. 5)

- “Society depends on space-based capabilities for global communications, navigation, weather forecasting, and much more,” said acting NASA Administrator Steve Jurczyk. “With commercial companies launching more and more satellites, it’s critical we increase communications, exchange data, and establish best practices to ensure we all maintain a safe space environment.”

- The Starlink spacecraft are equipped with global navigation satellite service receivers to estimate orbital parameters, an ion propulsion system, and an autonomous maneuvering capability that provide data for prompt and proactive exchange of information. Both NASA and SpaceX benefit from this enhanced interaction by ensuring all parties involved are fully aware of the exact location of spacecraft and debris in orbit.

- SpaceX has agreed its Starlink satellites will autonomously or manually maneuver to ensure the missions of NASA science satellites and other assets can operate uninterrupted from a collision avoidance perspective. Unless otherwise informed by SpaceX, NASA has agreed to not maneuver its assets in the event of a potential conjunction to ensure the parties do not inadvertently maneuver into one another.

- NASA and the Department of Defense have decades of experience in proactively managing collision risks, as well as potential impacts. Effective mitigation relies on inter-operator coordination, accurate data, a sound technical basis for risk analysis, as well as proactive processes for appropriate actions to mitigate risks. By working together through this agreement, the approach to collision avoidance can be improved for all users.

- In addition to this agreement, NASA is supporting growth in the U.S. commercial space sector through the release of the “Spacecraft Conjunction Assessment and Collision Avoidance Best Practices Handbook,” which the agency issued in December 2020 to improve global awareness of space activity and to share NASA lessons learned regarding close approach coordination and mitigation. The handbook is available at: https://go.nasa.gov/34f9ijM

• October 27, 2020: SpaceX has launched public beta testing of its Starlink communications satellite program that aims deliver high-speed Internet globally, particularly in underserved areas. 6)

- The Elon Musk-founded aerospace manufacturer sent out emails to invite people who signed up on its Starlink website to hear updates about the program.

- The initial Starlink service is called "Better Than Nothing Beta," according to multiple screenshots of an email, CNBC (Consumer News and Business Channel) reported.

- Joining the public beta test costs $99 a month on top of a $499 upfront cost for the ground equipment, which includes a user terminal to connect to the satellites, a mounting tripod and a Wi-Fi router.

- SpaceX also has a Starlink app listed on the Google Play and Apple iOS app stores, which helps users set up their systems and allows them to search areas of the sky for unobstructed views.

- "As you can tell from the title, we are trying to lower your initial expectations," the Starlink Team signed email said. "Expect to see data speeds vary from 50 Mb/s to 150 Mb/s and latency from 20 ms to 40 ms over the next several months as we enhance the Starlink system. There will also be brief periods of no connectivity at all."

- SpaceX said that "nearly 700,000" individuals across the United States had expressed interest in potentially subscribing to the service.

- "Under Starlink's Better Than Nothing Beta program, initial service is targeted for the U.S. and Canada in 2020, rapidly expanding to near global coverage of the populated world by 2021," SpaceX said in the description of its Starlink mobile app.

- The company rolled out private beta testing over the summer for which users had to agree to keep their experience confidential.

- "You may NOT discuss your participation in the Beta Program online or with those outside or your household, unless they are SpaceX employees," the Starlink website said.

- SpaceX said the network will cost about $10 billion or more to build, but the company's leadership estimates that it could bring in up to $30 billion a year, which is more than 10 times the annual revenue of its rocket business.

- On Saturday (24 October 2020), SpaceX launched its Falcon 9 rocket into space, carrying 60 Internet satellites into orbit to help establish connections to remote areas.

- Earlier this month, Musk tweeted that Starlink's constellation had grown large enough to begin beta-testing the Internet service system in the United States and southern Canada.

- The company has launched nearly 900 Starlink satellites to date, which is only a fraction of what's needed for global coverage, but enough to provide service in some areas.

• October 21, 2020: Microsoft and SpaceX announced a partnership Tuesday that would marry the tech leader's Azure computing system with space company's Starlink satellite Internet service. 7)

- Through Starlink, SpaceX plans to use thousands of satellites that would provide high-speed Internet anywhere on Earth. Microsoft's Azure would connect those satellite to the cloud storage.

- "The collaboration that we're announcing will allow us to work together to deliver new offerings for both the public and the private sector to deliver connectivity through Starlink for use on Azure," SpaceX President Gwynne Shotwell said in a video. "Where it makes sense, we will work with [Microsoft]: co-selling to our mutual customers, co-selling to new enterprise and future customers."

- Tom Keane, corporate vice president of Microsoft's Azure Global, said with the space community rapidly growing, new technologies have made connectivity and computing in space more attainable for private and public entities. He said such innovations can be used to benefit a wide range of fields from agriculture, energy, telecommunications and government.

- The partnership allows Microsoft to go head-to-head with Amazon and Starlink challenger Kuiper. That pairing would allow the e-commerce giant's AWS cloud to use satellites, as well.

- The Microsoft-SpaceX partnership will connect Starlink's network to Microsoft data centers around the world. Microsoft said it will mostly be used for customers "who need cloud computing capabilities in hybrid or challenging environments, including remote areas."

- "Resilient satellite communications, coupled with Azure's ability to provide high-performance computing, machine learning and data analytics opens many new opportunities for both public- and private-sector organizations," Keane said.

- "Our partnership approach to satellite communication solutions helps us bring these capabilities to customers faster to help solve their mission-critical space needs," he said.

• March 23, 2020: SpaceX has secured the approval of the Federal Communications Commission (FCC) to deploy up to a million ground antennas for its Starlink satellite constellation project. Previously, the company’s founder Elon Musk referred to the antenna as “a UFO on a stick.” 8)

- SpaceX recently came from the successful launch of its sixth batch of Starlink satellites. It is part of the company’s impressive project to deliver high-speed internet from space.

- Recently, the company was able to secure a key government license to begin rolling out another important feature of its Starlink project. According to federal documents filed by the company, the FCC has given SpaceX approval release about a million antennas that are designed to work with the Starlink satellites.

- According to the company, the antennas are designed to connect users to SpaceX’s network of satellites. Measuring at about 19 inches across, Musk noted that the antennas look like small UFOs. The SpaceX founder also said these devices are very easy to install and use.

- “It looks like a UFO on a stick,” he said according to CNBC. “It’s very important that you don’t need a specialist to install. The goal is for ... just two instructions and they can be done in either order: Point at sky, plug in.”

- SpaceX’s first batch of Starlink satellites was official deployed in May last year. Since then, the company has been regularly carrying out launches for new batches of satellites. Currently, there around 360 Starlink units operating in low-Earth orbit. The launch for the next batch of satellites is scheduled to take place next month.

- Originally, SpaceX planned to deploy a total of 12,000 satellites for its Starlink project. However, documents filed by the company last year revealed that SpaceX was planning to launch an additional 30,000 satellites. Once completed, the entire project could be comprised of about 42,000 satellites.

- As noted by the company, the massive satellite constellation will enable telecommunication companies to provide internet services to customers residing in remote and hard-to-reach regions in different parts of the globe.

- “With performance that far surpasses that of traditional satellite internet, and a global network unbounded by ground infrastructure limitations, Starlink will deliver high-speed broadband internet to locations where access has been unreliable, expensive, or completely unavailable,” SpaceX explained in a statement.

• January 17, 2020: SpaceX plans to launch its next group of Starlink broadband satellites aboard a Falcon 9 rocket as soon as Tuesday, Jan. 21, from Cape Canaveral, two days after the company is scheduled to launch a modified Falcon 9 booster from a separate facility at the Florida spaceport to test the Crew Dragon spaceship’s emergency escape system. 9)

- SpaceX’s ability to achieve back-to-back launch schedule hinges on several factors, including an expected test-firing in the coming days of the Falcon 9 booster slated to fly on the next Starlink launch.

- The Starlink mission — SpaceX’s fourth launch dedicated to the broadband network — was previously scheduled for Monday, Jan. 20. But sources said Friday the launch was pushed back to Jan. 21.

• January 8, 2020: SpaceX says it’s committed to working with the astronomy community to address the brightness of its Starlink satellites, but some astronomers remain concerned about the deleterious effect that system and other megaconstellations will have on their field. 10)

- One of the 60 satellites in the latest Starlink launch Jan. 6 featured an experimental coating intended to reduce its brightness. SpaceX said it will see in the coming weeks how well those coatings work, as well as study any effects they have on the performance of the satellite itself, before deciding how to move forward.

- “Our level of brightness and visibility was a surprise to us,” said Patricia Cooper, vice president of satellite government affairs for SpaceX, during a Jan. 8 special session on the topic of megaconstellation effects on astronomy during the 235th Meeting of the American Astronomical Society (AAS) in Honolulu. SpaceX President Gwynne Shotwell also said last month that SpaceX was surprised by the brightness of the satellites.

- Cooper said that brightness is affected by several issues. The Starlink satellites initially appear bright when released in a lower parking orbit, and the configuration of each satellites’ single large solar array when raising its orbit can also influence its brightness. Once in a final operating orbit of 550 kilometers, the spacecraft brightness decreases to a visual magnitude of about five, making them visible to the naked eye only in darker night skies.

- One challenge, she said, is the unique design of the satellite made it difficult to determine exactly what causes the spacecraft to reflect so much light. “It turns out, we think, that surfaces that scatter light, or reflect light diffusely, are also significant contributors,” she said. That led to the testing of surfaces on the experimental satellite, nicknamed “DarkSat” by some, to reduce that reflectivity.

- While DarkSat is now in orbit, it will take some time to see how effective it is. Patrick Seitzer, an astronomer at the University of Michigan who is studying the effect of satellite constellations on optical astronomy, said at a later press conference that the satellite likely won’t reach its operational orbit until late February. “Then serious measurements can begin,” he said.

- Cooper said that SpaceX would work quickly to reduce the brightness of its satellites, but didn’t give a specific timetable or state if other experimental satellites are in the works. In the meantime, the company will continue to launch the original design of Starlink satellites that are designed to be operational for five years, a plan that some astronomers at the meeting criticized.

- “We don’t know yet if these mitigations are useful and effective,” she said. “We tend to work very quickly. We tend to test, learn and iterate.”

- SpaceX has been meeting with a committee of the AAS to discuss the astronomy community’s concerns about Starlink and to examine ways to mitigate them. That work has included a half-dozen teleconferences and an in-person meeting during this AAS conference, said Jeff Hall, director of Lowell Observatory and chair of the AAS committee.

- “We have not had to cajole SpaceX in any way. They’ve been very receptive and very proactive,” he said. Those discussions, he said, initially focused on SpaceX’s Starlink deployment plans, but more recently have been more just “keeping in touch” as SpaceX prepared to launch its experimental DarkSat.

- Hall added that it was premature to discuss regulations regarding satellite brightness. “Regulation of the Wild West up there is necessary, but that is going to take a great deal of time to implement,” he said, while the problem posed by Starlink and other constellations is a near-term issue that needs to be addressed now.

- Hall added that it was premature to discuss regulations regarding satellite brightness. “Regulation of the Wild West up there is necessary, but that is going to take a great deal of time to implement,” he said, while the problem posed by Starlink and other constellations is a near-term issue that needs to be addressed now.

- Hall and other astronomers said that, like SpaceX, they were surprised by how bright the Starlink satellites appeared. “What surprised everyone — the astronomy community and SpaceX — was how bright their satellites are,” Seitzer said. “We knew these tens of thousands of megaconstellations were coming, but based on the sizes and shapes of things currently in orbit, I thought they’d be maybe eighth or ninth magnitude. We were not expecting second or third magnitude.”

- Both astronomers and SpaceX said they hope, as an initial step to get the Starlink satellites dim enough to not be visible to the naked eye even in the darkest skies. The next step will be to figure out what else can be done to mitigate their effects on major observatories, specifically the Vera Rubin Observatory (formerly Large Synoptic Survey Telescope) under construction in Chile. Astronomers said that wide-field telescope was particularly threatened by Starlink and other megaconstellation satellites.

- Hall said his AAS committee plans to start discussions with OneWeb later this month, shortly before the company begins full-scale deployment of its constellation. Six OneWeb demonstration satellites are currently in orbit, at altitudes higher than SpaceX. Seitzer said the satellites, at about eighth magnitude, are too dim to be seen by the naked eye, but pose in some cases greater concerns to professional astronomers than Starlink satellites because, at their altitudes, they may be visible all night during the summer, rather than just around sunset and sunrise.

- With SpaceX seeking to deploy up to 1,500 Starlink satellites in 2020 alone, and with OneWeb and other constellations under development, astronomers warned this was a major issue to them. “The issue of megaconstellations and astronomy is a serious issue,” Seitzer said. “We have a very short time to deal with this issue.”

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Figure 3: SpaceX says it's committed to reducing the brightness of its Starlink satellites, but while it works on that the company will continue to launch unmodified satellites (image credit: SpaceX)

• October 16, 2019: SpaceX wants spectrum access for nearly four times as many satellites as originally planned for its high-speed internet constellation, the company and a UN agency confirmed on 16 October. 11)

- On October 7, the US FCC (Federal Communications Commission) sent the Geneva-based ITU (International Telecommunication Union) 20 filings with each one asking permission for 1,500 satellites, the ITU's Alexandre Vallet, chief of space services department, told AFP (Agence France Presse).

- A SpaceX request for 12,000 satellites had already been approved. This new lot would add 30,000 to the network called Starlink.

- The ITU manages radio spectrum frequencies and satellite orbits around the world. The 20 new filings mentioned by the ITU official can be seen on its website.

- A SpaceX spokeswoman did not directly confirm that number but said the company "is taking steps to responsibly scale Starlink's total network capacity and data density to meet the growth in users' anticipated needs."

- The idea behind Starlink is that the network of mini-satellites will allow fast response time between user and internet provider.

- The grid created by all these satellites will be such that several of them will be in direct sight from any point on Earth.

- SpaceX launched the first 60 satellites in May and says the constellation will be operational for Canada and the northern US next year.

- It says it will take 24 launches for the rest of the world to be covered.

- To put things into context, there are currently 2,100 active satellites orbiting our planet, out of 23,000 objects recorded. These can be rocket stages, inactive satellites, space junk and other things.

- The prospect of adding another 42,000 satellites to the skies is causing worries for two reasons.

- On one hand, astronomers fear these satellites will get in the way of telescope observations made from Earth.

- When a first group of satellites was launched, many astronomers reported seeing a string of bright lights. SpaceX says it is trying to make the base of the satellites black.

- The second problem is crowding of LEO (Low Earth Orbit), which is up to altitudes of 2,000 km.

- SpaceX has said that three of the first 60 satellites it placed in orbit were out of service a month after being deployed. The company says it has ways of "deorbiting" faulty satellites and keeping them from colliding with other satellites.

- But an incident last month showed these procedures are not yet fully effective.

- ESA (European Space Agency) had to modify the trajectory of its Aeolus satellite to avoid collision with a Starlink orbiter. This is a routine maneuver. However, ESA tried to contact SpaceX and got no answer because the latter did not see the message.

• May 11, 2019: SpaceX CEO Elon Musk has published the first official photo of the company’s near-final Starlink design and confirmed that Falcon 9 will launch a staggering 60 satellites into orbit. 12)

- Known internally as Starlink v0.9, this mission will not be the first launch of operational satellites, but it will be the first internal SpaceX mission with a dedicated Falcon 9 launch. Additionally, the payload will be the heaviest yet launched by SpaceX, signifying an extraordinarily ambitious first step towards realizing the company’s ~12,000-satellite Starlink megaconstellation.

- Put simply, SpaceX’s Starlink v0.9 launch is extremely unique for several reasons. Aside from the unprecedented step of launching 60 spacecraft weighing ~13,000 kg on a developmental mission, both the form factor of each satellite and the style of dispenser/payload adapter has never been seen before. SpaceX appears to have settled on a square dispenser with four separate quadrants for satellites. The satellites themselves look truly bizarre – it’s actually difficult to discern where one spacecraft stops and the next begins.

- Nevertheless, it appears that each Starlink satellite is a relatively thin rectangle, possibly with a squared top and bottom. It’s also possible that they are all around rectangular and that the dispenser instead has two main sections. Either way, the very fact that the Starlink v0.9 payload can scarcely be parsed into recognizable satellites is thrilling. Aside from the rise of smallsats and cubesats, satellite design and engineering has been relatively stagnant for decades, particularly with respect to form factors and structural layouts. Most modern satellites are simply squarish boxes with electronics inside and payloads bolted on the outside.

- Despite using the same exact Falcon fairing that has been standard for years, SpaceX has managed to cram 60 spacecraft – each weighing around 227 kg into just the bottom two-thirds of the fairing, leaving a considerable amount of unused volume for future expansion.

- According to President and COO Gwynne Shotwell, Starlink v0.9 satellites are extremely close to SpaceX’s true final design. However, they are still considered by SpaceX to be a “test batch” of satellites and do not have the optical (laser) interlinks that will be a critical part of Starlink’s unique constellation design.

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Figure 4: The second phase of Starlink testing – 60 advanced satellites – stacked in a single fairing (image credit: SpaceX)

• April 30, 2019: The FCC has granted a request by SpaceX to begin launching spacecraft for the company’s Starlink broadband network to a lower orbit than originally planned, overruling protests by competitors and clearing a major regulatory hurdle before the launch of the first batch of Internet satellites from Cape Canaveral in May. 13)

- The regulatory commission approved SpaceX’s proposal Friday to fly more than 1,500 of its Starlink satellites at an altitude of 550 km, instead of the 1,150 km orbit originally planned.

- “This approval underscores the FCC’s confidence in SpaceX’s plans to deploy its next-generation satellite constellation and connect people around the world with reliable and affordable broadband service,” said Gwynne Shotwell, SpaceX’s president and chief operating officer. “Starlink production is well underway, and the first group of satellites have already arrived at the launch site for processing.”

• April 8, 2019: SpaceX has announced a launch target of May 2019 for the first batch of operational Starlink satellites in a sign that the proposed internet satellite constellation has reached a major milestone, effectively transitioning from pure research and development to serious manufacturing. 14)

- R&D will continue as SpaceX Starlink engineers work to implement the true final design of the first several hundred or thousand spacecraft, but a significant amount of the team’s work will now be centered on producing as many Starlink satellites as possible, as quickly as possible. With anywhere from 4400 to nearly 12,000 satellites needed to complete the three major proposed phases of Starlink, SpaceX will have to build and launch a minimum of ~2200 satellites in the next five years, averaging 37 high-performance, low-cost spacecraft built and launched every month for the next 60 months.

- Despite the major challenges ahead of SpaceX, things seem to be going quite smoothly with the current mix of manufacturing and development. As previously reported on Teslarati, SpaceX CEO Elon Musk forced the Starlink group through a painful reorganization in the summer of 2018, challenging the remaining leaders and their team to launch the first batch of operational Starlink satellites no later than June 2019. As a consequence, a sort of compromise had to be reached where one additional group of quasi-prototype satellites would be launched before settling on a truly final design for serious mass-production.

- According to SpaceX filings with the FCC, the first group of operational satellites – potentially anywhere from 75 to 1000 or more – will rely on just one band (“Ku”) for communications instead of the nominal two (“Ku” and “Ka”), a change that SpaceX says will significantly simplify the first spacecraft. By simplifying them, SpaceX believes it can expedite Starlink’s initial deployment without losing a great deal of performance or interfering with constellations from competitors like OneWeb.

• On 16 November 2018, the US Federal Communications Commission (FCC) announced it had authorized SpaceX to launch 7,518 satellites, adding to 4,425 satellites it has already approved. 15)

- None of the satellites has launched yet. SpaceX has six years to put half in orbit, and nine years to complete the satellite network, according to FCC rules.

• On 1 April 2018, SpaceX received US approval to launch 4,425 LEO (Low Earth Orbit) satellites, a key milestone in its plan to offer broadband with high speeds and low latency around the world. 16) 17)

- The FCC (Federal Communications Commission) issued an order approving SpaceX's application with some conditions. SpaceX intends to start launching operational satellites as early as 2019, with the goal of reaching the full capacity of 4,425 satellites in 2024. The FCC approval just requires SpaceX to launch 50 percent of the satellites by March 2024, and all of them by March 2027.

- "Grant of this application will enable SpaceX to bring high-speed, reliable, and affordable broadband service to consumers in the United States and around the world, including areas underserved or currently unserved by existing networks," the FCC order said.

- SpaceX's network (known as "Starlink") will need separate approval from the ITU (International Telecommunication Union). The FCC said its approval is conditioned on "SpaceX receiving a favorable or 'qualified favorable' rating of its EPFD (Equivalent Power Flux-Density) limits demonstration by the ITU prior to initiation of service." SpaceX will also have to follow other ITU rules.

• February 22, 2018: SpaceX has launched with the debuting of an upgraded payload fairing for the Falcon 9 rocket during Spain’s PAZ satellite lofting from Vandenberg Air Force Base. The launch carried the first two demonstration satellites for SpaceX’s own satellite internet constellation. The launch occurred at an instantaneous launch opportunity at 06:17 Pacific Time (14:17 UTC) on 22 February 2018. 18)

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Figure 5: SpaceX’s first two Starlink prototype satellites are pictured here before their inaugural launch, showing off a thoroughly utilitarian bus and several advanced components. They were launched as secondary payloads with the Spanish radar observation satellite (PAZ) on a Falcon 9 rocket from Vandenberg Air Force Base, California. SpaceX called these two prototype Starlink satellites, Tintin-A and Tintin-B (image credit: SpaceX)




The SpaceX launches of the Starlink constellation are presented in reverse order.


Launch 24: SpaceX continued the rollout of its Starlink broadband constellation with another launch of 60 satellites April 7, edging closer to providing continuous global service. 19)

- A Falcon 9 lifted off from Space Launch Complex 40 at Cape Canaveral Space Force Station at 12:34 p.m. EDT (16:34 UTC) on 7 April 2021. The rocket’s upper stage deployed its payload of 60 Starlink satellites into orbit a little more than an hour later.

- The rocket’s first stage landed on a droneship in the Atlantic eight and a half minutes after liftoff. This was the seventh flight for this booster, which first launched the Demo-2 commercial crew mission last May and most recently launched another set of Starlink satellites March 11.

- This was the 10th Falcon 9 launch of the year for SpaceX, eight of which have been dedicated to Starlink satellites. The company now has 1,378 satellites in orbit when accounting for those launched and subsequently deorbited, according to statistics maintained by Jonathan McDowell.

- That constellation is now nearing the size needed to provide at least basic service globally. “We do have global reach, but we don’t have yet have full connectivity globally,” Gwynne Shotwell, president and chief operating officer of SpaceX, said during an April 6 panel discussion at the Satellite 2021 LEO Digital Forum.

- “We hope after about 28 launches we’ll have continuous coverage throughout the globe,” she added. This launch is the 23rd of v1.0 satellites, although a few v0.9 satellites launched nearly two years ago remain in orbit, along with 10 v1.0 satellites launched into polar orbit on a rideshare mission in January. That suggests the company will reach the continuous coverage milestone after four to five more launches.

- Those launches would push SpaceX against its current FCC authorization, which allows the company to operate up to 1,584 satellites in orbits at approximately 550 km. The company’s current license from the Federal Communications Commission allows it to operate 2,825 additional satellites at altitudes of 1,100 to 1,300 km. SpaceX had filed a request with the FCC to modify that license, moving those additional satellites to 550 km.

- The FCC has yet to rule on that modification, but SpaceX’s current launch rate means the company will hit its current limit of satellites at 550 km within a couple months. Shotwell mentioned during the panel that the company is “bringing our satellites down from our original altitude” to address space sustainability concerns. She did not, though, address the FCC license modification issue beyond saying that the company would continue launching satellites “as we’re allowed.”

- Shotwell said the company would press ahead with Starlink launches even after hitting the threshold of continuous global coverage. “The plan after that is to continue to add satellites to provide additional capacity,” she said. That includes launching additional satellites to polar orbit beginning this summer from Vandenberg Air Force Base in California. Those polar satellites, she said, will likely include laser intersatellite links that the company has experimented with on a few Starlink satellites.

- The element of the overall Starlink effort that has attracted the most attention is the series of launches that has created the world’s largest satellite constellation in less than two years. That has not necessarily been the biggest challenge for SpaceX, though.

- “The satellites and launch have been pretty straightforward for us. We thought we’d struggle a little bit more on the satellites, but it turns out our Dragon, which is a very sophisticated satellite, helped us tremendously in figuring out the satellite architecture for Starlink,” she said.

- What has been a challenge, she said, is dealing with a growing number of customers and building a reliable network, but “none of which we can’t solve.”

- Starlink remains in a beta test in the United States and several other countries. Shotwell said there are no plans to end the beta test and move into full commercial service in the near future. “We still have a lot of work to do to make the network reliable,” she said. “We’ll move out of beta when we have a really great product that we are very proud of.”

- Another area of effort has been on the ground equipment used by Starlink subscribers, notably the electronically steerable antenna. Shotwell said the company has been working to reduce the cost of that equipment, which is required to win wide-scale adoption.

- “We have made great progress on reducing the cost of our terminal,” she said. That equipment originally cost about $3,000. “We’re less than half of that right now.”

- Customers currently pay about $500 for that equipment, meaning that SpaceX is still significantly subsidizing those terminals. That may change, though, as the company makes continued progress to lower costs. “We do see our terminals coming in the few-hundred-dollar range within the next year or two.”

- Shotwell appeared on a panel with executives of several other satellite operators, many of whom argued that hybrid systems that use satellites in low and medium Earth orbits as well as geostationary orbit, or GEO satellites alone, offer better solutions. “We see absolutely no way, no possibility, that those low-orbit constellations can fulfill the latent demand of all the unserved population today,” said Rodolphe Belmer, chief executive of Eutelsat.

- As Belmer and other executives on the panel expressed their reservations about LEO constellations, Shotwell smiled. “I just always smile, by the way, when people make projections about what can and can’t be done with technology,” she said. “I don’t think we have any idea how technology can evolve five years from now.”


Launch 23: A SpaceX Falcon 9 launched another set of Starlink satellites 24 March 2021, 15 years to the day after the company’s first, unsuccessful launch. 20)

- The Falcon 9 lifted off from Space Launch Complex 40 at Cape Canaveral Space Force Station at 08:28 UTC (4:28 a.m. EDT). The rocket’s upper stage deployed its payload of 60 Starlink satellites into low Earth orbit 64 minutes later.

- The rocket’s first stage, on its sixth flight, landed on a droneship in the Atlantic Ocean eight and a half minutes after liftoff. That booster, which first launched last June carrying a GPS satellite, also launched Turksat 5A in January as well as three other Starlink missions.

- This launch, by coincidence, took place exactly 15 years after SpaceX conducted the first launch of its Falcon 1 rocket from Kwajalein Atoll in the Pacific Ocean. That March 24, 2006, launch was unsuccessful, as the first stage’s single engine failed about half a minute after liftoff.

- Two subsequent Falcon 1 launches also failed before the fourth Falcon 1 launch, carrying a test payload, reached orbit in September 2008. The Falcon 1 flew one more mission in 2009 before SpaceX retired the vehicle in favor of the far larger Falcon 9, which has become the company’s workhorse with more than 110 launches since its introduction in 2010.

- This launch was the ninth Falcon 9 mission of 2021 and the fourth this month. Seven of those nine launches, including all four in March, have been dedicated to Starlink, increasing the size of the constellation to more than 1,300 satellites.

Growing capacity and international expansion

- The growth of that constellation has been enabled by both the high launch cadence of the Falcon 9 and mass production of satellites. “We’re currently building roughly six satellites a day at our factory in Seattle, which is pretty remarkable,” Jonathan Hofeller, SpaceX vice president for Starlink, said at Spacetide, a Japanese space business conference, held online March 23. He said the company has maintained that production rate for about a year so far.

- The satellites launched to date, he said, are all first-generation, or “Gen 1,” spacecraft. “We’re already working on the Gen 2 constellation,” he said. “These satellites will be continuously refreshed as we continue to increase both the network capacity and the density by orders of magnitude. We’re excited to be able to eventually provide a lot more internet than we’re even doing now.” He didn’t disclose additional details about the Gen 2 satellites or their schedule.

- SpaceX plans to have global coverage for Starlink by the end of this year. However, as the company expands beta tests in the United States and several other countries, Hofeller noted that the satellite constellation alone is just one element of that rollout. Other key factors include establishing ground stations to serve as gateways as well as the regulatory process, which varies from country to country.

- That regulatory process, he said, can be “very challenging” as the company explains its system to national regulators. “That process just takes a while.”

- Japan, he suggested, is one the countries where that regulatory process is stretched out. Hofeller said the company identified Japan as a country where it wanted to provide service relatively early, and thanked those who have advocated for Starlink to Japanese regulators. “Anything they can do to speed up the regulatory process will be greatly appreciated,” he said, projecting that Starlink service could begin in Japan “as soon as the very end of this year.”

- SpaceX has largely marketed Starlink directly to consumers, a move he said is intended to reduce costs to those customers while also providing a direct feedback loop to SpaceX to help it improve the service. However, as the company expands Starlink into other markets, which range from backhaul services for telecommunications providers to mobility applications, Hofeller said the company would be open to working with partners.

- “We are a rocket company,” he said. “As we grow the capacity, it could be inevitable that we have partners globally.”


Launch 22: A Falcon 9 launched another set of 60 Starlink satellites March 14, 2021, with the rocket’s first stage setting a record with its ninth launch and landing. 21)

- The Falcon 9 lifted off from Launch Complex 39A at the Kennedy Space Center at 6:01 a.m. EST (10:01 UTC) . The upper stage deployed its payload of 60 Starlink satellites into orbit 65 minutes later, bringing the size of the broadband internet constellation to 1,260 satellites.

- The launch was the eighth for the Falcon 9 this year, and took place a little more than 72 hours after another Falcon 9 launch of Starlink satellites. Six of the eight Falcon 9 launches this year have been dedicated to Starlink, and one of the other two, the Transporter-1 dedicated rideshare flight, also carried 10 Starlink satellites.

- The rocket’s first stage landed on a droneship in the Atlantic Ocean eight and a half minutes after liftoff. That booster was on its ninth flight, a record for the Falcon 9. The rocket, which first launched a Crew Dragon spacecraft on the uncrewed Demo-1 mission in March 2019, later launched the RADARSAT Constellation Mission and the SXM-7 satellite for SiriusXM. It launched five Starlink missions before this one, including the booster’s previous flight Jan. 20.

- The booster is now approaching the goal SpaceX set of being able to fly 10 times. However, one company official recently said it may be possible to exceed that goal.

- “We’re learning a lot about refurbishment and we’re learning where the areas are where we need to pay attention to,” said Hans Koenigsmann, senior adviser for build and flight reliability at SpaceX, during a panel discussion at the 47th Spaceport Summit last month. Those areas that require special attention include the booster’s heat shield and engine components. “We’ve been learning with every single landing.”

- Some of those lessons have been hard ones. One booster failed to land after a Feb. 15 launch, breaking a streak of successful landings lasting nearly a year. The company later said an engine shut down during flight when hot gas got through a hole in an engine cover that was a “life leader” in the Falcon 9 fleet, with more launches than any others in the Falcon 9 fleet. The shutdown meant the booster did not have enough thrust for a landing on a droneship.

- “The more you fly, the more you learn,” Benji Reed, senior director for human spaceflight programs at SpaceX, said of the failed landing at a March 1 briefing about the upcoming NASA Crew-2 commercial crew mission. “That’s a great lesson that we learned from these very long life leader components and vehicles.” Those lessons, he said, included revised plans to inspect and replace components.

- Once a booster reaches the milestone of 10 flights, “we will continue to look at that booster and make an assessment whether we can move forward with it,” Koenigsmann said. He suggested the booster may be able to continue to operate, perhaps after replacing some components that wear out. “I don’t think the number 10 is a magic number.”


Launch 21: A SpaceX Falcon 9 launched another set of 60 Starlink satellites March 11, 2021 (08:13 UTC) as the company expanded international service in several countries. 22)

- The Falcon 9 lifted off from Space Launch Complex 40 at Cape Canaveral Space Force Station at 3:13 a.m. EST. The rocket’s upper stage deployed its payload of 60 Starlink satellites 65 minutes after liftoff.

- The rocket’s first stage successfully landed on a droneship eight and a half minutes after liftoff. That booster was on its sixth flight, having previously flown missions ranging from the Demo-2 commercial crew test flight in May 2020 to, most recently, the Transporter-1 rideshare mission on 24 January 2021.

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Figure 6: A Falcon 9 launch March 11 brought the total number of Starlink satellites in orbit to 1,200 (image credit: SpaceX webcast)

- SpaceX now has 1,200 Starlink satellites in orbit, having launched 310 of them this year alone. Five of SpaceX’s seven Falcon 9 missions in 2021 have been dedicated for Starlink, with the other two launching Transporter-1 and the TurkSat-5A geostationary communications satellite. The Transporter-1 launch included 10 Starlink satellites, the first deployed into polar orbit.

- As SpaceX expands the Starlink satellite constellation, the company is also expanding the coverage for its ongoing beta test of the broadband internet service those satellites provide. The company originally limited the beta test to the northern tier of the continental United States, later expanding it to include southern Canada and parts of the United Kingdom.

- During the webcast for this Starlink launch, the company said it is now expanding its service in the U.K., which had been limited to southern England, to the rest of England, Scotland and Wales. SpaceX is also starting service in western Germany and the South Island of New Zealand, with plans to expand in both countries in the coming weeks.

- SpaceX has kept expectations low for the beta test, called “Better Than Nothing” by the company, with average speeds of 50 to 150 Mbit/s and occasional outages. In online forums, though, some users have reported much higher speeds at times, exceeding 300 Mbit/s, but still with intermittent outages.


Launch 20: Launching through a blanket of low-hanging clouds and light mist, a SpaceX Falcon 9 rocket thundered into the sky over Florida’s Space Coast early Thursday and delivered 60 more Starlink internet satellites to orbit. The rocket’s first stage touched down on SpaceX’s floating landing platform in the Atlantic Ocean to complete its eighth trip to space and back. 23)

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Figure 7: A Falcon 9 rocket disappears in a blanket of clouds shortly after launching from NASA’s Kennedy Space Center early Thursday. (image credit: SpaceX)

- On March 4, 2021, a Falcon 9 rocket of SpaceX lifted off from pad 39A at the Kennedy Space Center at 3:24:54 a.m. EST (08:24:54 GMT). Arcing toward the northeast, the Falcon 9 exceeded the speed of sound and dropped its first stage booster about two-and-a-half minutes after liftoff. A single Merlin engine on the upper stage ignited to continue the flight into space, while the first stage descended to a propulsive landing on the drone ship “Of Course I Still Love You” positioned about 400 miles (630 km) downrange from Cape Canaveral.

- The successful landing marked the 75th intact recovery of a Falcon rocket booster since December 2015. The booster on Thursday mission — designated B1049 — made its eighth launch and landing after debuting in September 2018, tying another first stage for the most number of flights in SpaceX’s fleet.

- A Falcon 9 booster on SpaceX’s previous launch Feb. 15 failed to land on the drone ship after one of its nine main engines shut down prematurely during ascent.

- After reaching a preliminary parking orbit, the upper stage coasted halfway around the world before firing its engine again for a one-second orbit adjustment burn over the Indian Ocean. The 60 Starlink satellites deployed from the Falcon 9’s upper stage at 4:29 a.m. EST (09:29 GMT) while flying 172 miles (278 km) above Earth just south of New Zealand.

- The on-target launch came after a series of delays kept the mission grounded since late January. The delays were caused by weather and unspecified technical issues, and two other Falcon 9 missions with Starlink satellites took off from nearby pad 40 at Cape Canaveral Space Force Station while the flight from pad 39A stayed earthbound.

- The change in the order of missions meant the batch launched Thursday was on the 20th Falcon 9 flight dedicated to carrying Starlink satellites, despite its designation on the military-run Eastern Range as Starlink V1.0-L17. Launches No. 18 and 19 ended up flying before No. 17.

- The 60 Starlink satellites, each weighing about a quarter-ton, will unfurl their solar panels and switch on ion krypton thrusters to begin raising their altitude to 341 miles (550 km) in the coming weeks. At that altitude, the satellites will join more than 1,000 active Starlink satellites flying in orbits inclined 53 degrees to the equator, taking them above nearly all of the world’s populated regions.

- SpaceX has launched 1,205 Starlink satellites to date with the 60 fresh relay stations delivered to orbit Thursday. But 63 of the Starlinks have been intentionally deorbited or re-entered the atmosphere after failing, and another 20 are not maneuvering or appear to be in the process of deorbiting, according to a tally of Starlink satellites from Jonathan McDowell, an astronomer and respected tracker of spaceflight activity.

- SpaceX is well on the way to finish deployment of its initial tranche of 1,584 Starlink stations — including spares — later this year. SpaceX won’t stop there, with plans to launch additional orbital “shells” of Starlink satellites into polar orbit to enable global coverage, with a first-generation fleet totaling some 4,400 spacecraft.

- The Federal Communications Commission has authorized SpaceX to eventually operate up to 12,000 Starlink satellites.

- The company is already providing an interim level of service over parts of the Earth, such as Canada, northern parts of the United States, and the United Kingdom. Beta testing of the Starlink services is already underway with users in those regions. SpaceX is also accepting pre-orders from Starlink consumers, who can pay $99 to reserve their place in line to get Starlink service when it becomes available in their area. For people in the southern United States and other lower-latitude regions, that should come by late 2021, SpaceX says.

- Once confirmed, customers will pay $499 for a Starlink antenna and modem, plus $50 in shipping and handling, SpaceX says. A subscription will run $99 per month.


Launch 19: SpaceX successfully launched another Falcon 9 rocket carrying a set of 60 Starlink V1.0 minisatellites into space on 16 February 2021 (03:59 UTC, corresponding to 10:59 p.m. EST on 15 February) from Cape Canaveral SLC-40. The SpaceX rocket released its payload of 60 Starlink satellites in orbit 65 minutes after liftoff. 24)

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Figure 8: A set of 60 Starlink satellites deploys from the upper stage of its Falcon 9 rocket to conclude a Feb. 15 launch (image credit: SpaceX webcast)

- This time around, the rocket's first stage suffered a rare failed landing. The first stage did not land on a droneship in the Atlantic Ocean as planned. Video from the droneship around the time of landing showed a glow in the distance, suggesting a problem with the booster that either caused it to go off-course or to deliberately divert from the landing attempt. SpaceX did not immediately disclose what took place during the failed landing.

- The failure broke a streak of 24 consecutive Falcon 9 launches with successful landings, either on droneships or on land. The last failure took place in March 2020, and was the second failure in three Falcon 9 launches. The March failure was caused by engine cleaning fluid that was trapped inside and interfered with a sensor, while the earlier failure was blamed on incorrect wind data.

- The booster on this launch made its sixth flight. It first flew in December 2019 on a cargo Dragon mission, then was used for another cargo Dragon in March 2020. It subsequently launched a set of Starlink satellites, along with three SkySats for Planet, in June, followed by SAOCOM-1B in August and the NROL-108 mission for the National Reconnaissance Office in December.

- The primary purpose of the mission, though, was a success, adding to the growing constellation of Starlink satellites. SpaceX is expanding its beta testing program, and now has more than 10,000 users in the United States, Canada and the United Kingdom, according to a Feb. 3 filing with the Federal Communications Commission.

- SpaceX, though, is facing renewed opposition from some organizations regarding the nearly $885.5 million in FCC Rural Digital Opportunity Fund (RDOF) awards it won in December. In a recent white paper, the National Rural Electric Cooperative Association and National Rural Telecommunications Cooperative (NRTC) argued that the FCC should closely scrutinize SpaceX’s plans to provide broadband internet service via satellite. Those groups say bids by rural cooperatives for RDOF funding to provide broadband service were shut out by both SpaceX as well as fixed wireless networks.

- “While delivering broadband service at the speeds promised by these applicants may appear to be viable, this service is currently in beta testing and commercially available on a limited basis in extremely limited areas, and questions remain,” the paper states. “Awarding bids to experimental and unproven LEO satellite service is a direct contradiction” to the rules of the RDOF program, it argued.

- “I’m really struggling on the physics and economics” of satellite broadband, said Tim Bryan, chief executive of the NRTC, in a Feb. 4 call with reporters. He claimed there were “anecdotal reports” of people who signed up for Starlink beta but were having problems getting connections any faster than four megabits per second, but didn’t elaborate.

- “Starlink’s performance is not theoretical or experimental,” SpaceX noted in its Feb. 3 FCC filing. The company said it had already demonstrated it could meet or exceed key performance tiers, including 100 megabits per second of data to customers and 20 megabits per second of data from them, as well latencies of 31 milliseconds or less.

- Bryan said his group’s issue was how Starlink could scale up to serve larger numbers of customers. “My concern is mostly around the capacity not of one or two users, but what happens when you get to 20 or 30 or 40 or 50 thousand users,” he said.

- “I have no doubt that the Starlink constellation could be successful in some areas, and in some cases, providing coverage over areas like the deep blue seas and those sorts of places,” he said. “I struggle to see how it’s going to reliably deliver 100-megabit service to the literally hundreds and thousands of customers in the census block groups that it bid for.”


Launch 18: SpaceX successfully launched another set Starlink satellites February 4, 2021 in the first of back-to-back Falcon 9 launches scheduled from Cape Canaveral. The Falcon 9 rocket lifted off at 1:19 a.m. Eastern (06:19 UTC) from Space Launch Complex 40 at Cape Canaveral Space Force Station. Its payload of 60 Starlink satellites separated from the rocket’s upper stage 65 minutes later. 25)

- The rocket’s first stage landed on a droneship in the Atlantic Ocean eight and a half minutes after liftoff. The booster was on its fifth flight, having been used most recently for the launch of the Turksat 5A satellite Jan. 8.

- The launch is the first of two back-to-back Falcon 9 Starlink missions from Florida. A second Falcon 9 is scheduled to launch Feb. 5 from Launch Complex 39A at the Kennedy Space Center, also carrying 60 Starlink satellites.

- For a time, SpaceX planned launching both rockets Feb. 4, less than four and a half hours apart. The company said late Feb. 2 that the launch doubleheader was pending favorable weather and range approvals. While the 45th Space Wing announced Feb. 3 that it approved SpaceX’s launch plans, the company announced later that day it was delaying the launch from LC-39A, which had been scheduled for 5:36 a.m. Eastern, by a day for additional pre-launch checks. — Note: The next launch of SpaceX with a set of 60 Starlink satellites is now postponed to February 15.

- The last time two launches took place from the Eastern Range, which includes Cape Canaveral Space Force Station and KSC, in a single day was in November 1966, with launches of NASA’s Gemini 12 mission and its Atlas Agena docking target 99 minutes apart. SpaceX proposed carrying out two Falcon 9 launches in one day in August 2020, but one of the two launches was scrubbed by weather.


Launch 17: SpaceX first Rideshare mission called Transporter-1. On January 24, 2021 at 15:00 UTC (10 a.m. EST), SpaceX launched a Falcon 9 Block 5 rocket from the Cape Canaveral Air Force Station (SLC-40) with 143 small satellites, a record number of spacecraft on a single mission, giving a boost to startup space companies and stressing the U.S. military’s tracking network charged with sorting out the locations of all objects in orbit. 26)

- This SpaceX mission carried also 10 Starlink satellites into orbit. The other satellites on this Rideshare mission will be listed in the separate Transporter-1 file on the eoPortal.

- SSO orbit of Rideshare mission: SpaceX sent this mission with its 10 Starlink satellites into a polar SSO (Sun-Synchronous Orbit) with permission of the FCC (Federal Communications Commission). Altitude of 560 km and inclination of 97.6º (Ref. 54).
The Falcon 9 rocket soared toward the southeast from the launch pad at Cape Canaveral, then vectored its thrust to fly on a coast-hugging trajectory toward South Florida, before flying over Cuba, the Caribbean Sea, and Central America. The unusual trajectory was similar to the track followed by a Falcon 9 launch in August 2020, which was the first launch since the 1960s from Florida’s Space Coast to head into a polar orbit.

- The Falcon 9’s reusable first stage booster — flying for the fifth time — landed on SpaceX’s “Of Course I Still Love You” drone ship in the Atlantic Ocean southeast of Miami nearly 10 minutes after liftoff. SpaceX said it also retrieved the rocket’s payload fairing halves after they parachuted back to Earth in the Atlantic.

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Figure 9: This photo shows the stack of 143 small satellites aboard SpaceX’s Transporter-1 mission before encapsulation inside the Falcon 9 rocket’s payload shroud (image credit: SpaceX)


Launch 16: SpaceX launched its latest set of 60 Starlink satellites Jan. 20, 2021, bringing the total number of spacecraft launched so far for that broadband constellation to more than 1,000. 27) 28)

- The Falcon 9 lifted off at 8:02 a.m. Eastern (13:02 UTC on 20 January) from Launch Complex 39A at the Kennedy Space Center. The rocket’s upper stage deployed the payload of 60 Starlink satellites 65 minutes after liftoff.

- The rocket’s first stage, making its eighth flight, landed on a droneship in the Atlantic Ocean. SpaceX cautioned during the webcast of the launch that the potential for high ground-level winds made the landing an “envelope expansion” attempt. However, the stage landed without incident in the center of the droneship.

- The launch was the first time SpaceX flew a booster eight times. The booster, first used to launch the Demo-1 commercial crew test flight in March 2019, was most recently flown on the SXM-7 launch Dec. 13. The 38-day turnaround time between launches is also a record for the shortest time between flights of the same booster.

- With this launch, SpaceX has now delivered 1,015 Starlink satellites into orbit, dating back to the two “Tintin” prototypes launched in February 2018. Of those 1,015, 951 are still in orbit, according to statistics maintained by spaceflight observer Jonathan McDowell.

- SpaceX ramped up deployment of Starlink last year, with 14 launches. The rapid growth of the constellation has alarmed astronomers, who are concerned that Starlink and other megaconstellations could disrupt their observations.

- Speaking during a session of the 237th Meeting of the American Astronomical Society Jan. 14, Patricia Cooper, vice president of satellite government affairs at SpaceX, argued that the company has taken major steps to reduce the impact of Starlink satellites on astronomy over the last year.

- “We at SpaceX have certainly enjoyed what I would call a thoughtful and creative technical collaboration with an ever-widening group of astronomers,” she said, resulting in a “deeper and fuller technical understanding of the intersection of the satellite constellation sector and specific projects affect ground-based astronomy.”

- That has resulted in the development of a version of the Starlink satellites called VisorSat, which is equipped with visors to prevent sunlight from reflecting off antennas and other surfaces on the satellites, reducing their brightness. Every Starlink satellite launched after August 2020 is equipped with visors, accounting for more than 400 satellites, she said.

- The goal of the VisorSats is to reduce the brightness of the Starlink satellites to magnitude 7 or fainter. Observations of those satellites that have reached their final orbit, though, indicate they have an average magnitude of 6.5, said Pat Seitzer of the University of Michigan during the conference session.

- Cooper said SpaceX is committed to continue to work with astronomers to mitigate the effect of Starlink, but also emphasized the benefits of the system. “It’s important to keep the purpose of this disruption to astronomy, from your perspective, in context of the goal of the constellation we’re deploying, which is broadband connectivity,” she said.

- “This collaboration needs to continue,” she added, because those discussions are “what’s getting us to a much better, more successful way of coexisting.”

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Figure 10: A Falcon 9 rocket, flying with a first stage flown on seven previous missions, climbs through the atmosphere Wednesday (20 January) over Florida’s Space Coast (image credit: SpaceX)


Launch 15: The 100th flight of a Falcon 9 rocket delivered 60 satellites to orbit for SpaceX’s Starlink network on 25 November 2020 (02:13 UTC, corresponding to 09:13 p.m. EST on 24 November), adding another building block to a planned fleet of thousands of solar-powered space-based relay stations to beam broadband connectivity around the world. 29)

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Figure 11: A Falcon 9 rocket climbs away from pad 40 at Cape Canaveral Air Force Station on 24 November 2020 (image credit: SpaceX)

- The successful mission also set a new record for SpaceX’s rocket reuse program — one that could be broken again within months if SpaceX maintains its feverish launch cadence. For the first time, a reusable Falcon 9 booster completed its seventh trip to space and back on this flight.

- The rocket's 15-story first stage booster dropped away from the Falcon 9 upper stage about two-and-a-half after liftoff, setting a course for a controlled touchdown on SpaceX’s drone ship “Of Course I Still Love You” positioned several hundred miles northeast of Cape Canaveral in the Atlantic Ocean.

- The booster — designated B1049 in SpaceX’s rocket inventory — reignited its center engine for a braking maneuver just before touchdown, then extended a landing gear before settling onto the deck of the drone ship. The apparently flawless landing punctuated the seventh mission of the B1049 vehicle, making it SpaceX’s “fleet leader.”

- Along with its reused first stage booster, the Falcon 9 launched with a recycled clamshell-like payload shroud, half of which flew on two previous missions. The other half of the fairing was a veteran one prior launch.

- Two recovery vessels were dispatched to sea to retrieve the fairing halves from Tuesday night’s mission after they parachuted back to Earth from space.

- While the booster and fairing shells descended back to Earth, the Falcon 9’s upper stage guided the 60 flat-panel Starlink satellites into a transfer orbit inclined 53 degrees to the equator. Around 15 minutes after liftoff, the upper stage released retention rods to allow the stack of 60 spacecraft to fly free from the rocket over the North Atlantic Ocean.

- The Falcon 9 aimed to place the satellites into an elliptical orbit ranging between 132 miles (213 km) and 227 miles (366 km). A member of SpaceX’s launch team confirmed on a mission audio loop that the rocket achieved an on-target orbital insertion.

- The quarter-ton Starlink satellites, built by SpaceX in Redmond, Washington, were expected to unfurl power-generating solar arrays and prime their krypton ion thrusters to begin raising their orbits to an operational altitude of 341 miles (550 km), where they will join more than 800 other Starlink relay stations to beam broadband internet signals across most of the populated world.

- With this launch, SpaceX has deployed 955 Starlink satellites into orbit.


Launch 14: SpaceX successfully deployed 60 more Starlink internet satellites in orbit Saturday, continuing a record launch cadence while engineers assess a concern with Falcon -9 rocket engines that has delayed other missions, including the next crew flight to the International Space Station. 30)

- The 60 Starlink satellites were launched from SLC-40 at Cape Canaveral Air Force Station at 15:31:34 GMT on 24 October 2020. The mission was delayed from Thursday to allow time for engineers to assess a problem with a camera on the Falcon-9 rocket’s upper stage.

- The rocket’s first stage shut down its engines and separated two-and-a-half minutes into the mission, beginning a controlled descent to a pinpoint landing on a floating platform parked some 630 km northeast of the launch site.

- The landing concluded the third trip to space and back for the reusable Falcon-9 booster — designated B1060 — and the touchdown occurred moments before the rocket’s upper stage delivered the 60 Starlink satellites into a preliminary parking orbit.

- SpaceX did not try to catch the Falcon-9’s two-piece payload fairing as they fell back to Earth under parachutes. A nose cone structure damaged a net on one of SpaceX’s fairing recovery vessels on the company’s most recent launch Oct. 18.

- Instead, SpaceX dispatched one of the boats from its fleet to retrieve the fairing structures from the Atlantic Ocean for inspections, refurbishment, and potential use on a future flight.

- After coasting across the Atlantic Ocean, Europe and the Middle East, the Falcon-9’s upper stage briefly reignited its single engine at T+plus 44 minutes to inject the Starlink satellites into a near-circular orbit at an altitude of roughly 275 km with an inclination of 53º to the equator.

- All 60 satellites, which were flat-packed on top of the Falcon 9 rocket for launch, separated from the upper stage at 16:34 GMT. A live video feed from the rocket showed the flat-panel satellites receding from view as they flew south of Tasmania.

- The satellites, built by SpaceX in Redmond, Washington, were expected to unfurl power-generating solar arrays and prime their krypton ion thrusters to begin raising their orbits to an operational altitude of 550 km, where they will join more than 800 other Starlink relay stations to beam broadband internet signals across most of the populated world.

- SpaceX says the Starlink network — designed for low-latency internet service — is still in its early stages, and engineers continue testing the system to collect latency data and speed tests. In a filing with the FCC dated Oct. 13, SpaceX said it has started beta testing of the Starlink network in multiple U.S. states, and is providing internet connectivity to previously unserved students in rural areas.


Launch 13: SpaceX launched 60 more Starlink internet relay platforms into orbit on 18 October 2020 (Sunday, 12:25:57 UTC) from LC-39A at the Kennedy Space Center, as the company ramps up network testing in Washington state and touts a streak of nearly 300 satellites launched since June without a spacecraft failure. 31)

- After 2.5 minutes into the flight, the first stage booster shut down its engines and detached to begin descending toward SpaceX’s drone ship “Of Course I Still Love You” in the Atlantic Ocean.

- The second stage’s single Merlin engine ignited to continue the mission into orbit, and the Falcon 9’s two-piece nose shroud jettisoned nearly three-and-a-half minutes into the flight.

- The first stage booster nailed its landing on SpaceX’s drone ship around 400 miles (630 km) northeast of Cape Canaveral. It was the sixth trip to space and back for this particular booster — designated B1051 — after its debut on an unpiloted test flight of the Crew Dragon spacecraft in March 2019.

- At the same time, the Falcon 9’s upper stage delivered the 60 Starlink internet satellites into a preliminary orbit. The upper stage engine later reignited to maneuver the payloads into a near-circular orbit 278 km above Earth, with an inclination of 53 degrees to the equator.

- The 60 flat-panel satellites separated from the rocket at 9:29 a.m. EDT (13:29 GMT) to conclude SpaceX’s 70th straight successful mission. A camera on the upper stage showed the 60 satellites — each with a mass of about a quarter-ton — flying free of the Falcon 9 over the Indian Ocean.

- SpaceX said its two fairing recovery ships caught both halves of the fairing from Sunday’s launch as the clamshells came back to Earth under parachutes. The net on one of the vessels gave way as the fairing settled into orbit, but SpaceX said its ocean-going recovery team was OK.

- With the satellites launched Sunday, SpaceX has placed 835 Starlink broadband relay stations into orbit, including prototypes that won’t be used for commercial service. That extends SpaceX’s lead in operating the largest fleet of satellites in orbit.

• October 18, 2020: With this launch, SpaceX has now placed 835 Starlink satellites into orbit. However, more than 50 of those satellites have since reentered, including 45 of the 60 “v0.9” Starlink satellites launched in May 2019 and the first two “Tintin” prototypes launched in February 2018. 32)

- Starlink is currently in a private beta test of its broadband internet system, and the company has said it plans to offer a more public beta test before the end of the year. In both the launch webcast as well as recent filings with the Federal Communications Commission, the company has highlighted early users of the system, such as the emergency management department in the state of Washington, which used Starlink to provide connectivity during recent wildfires in the state, as well as the Hoh tribe in the state, which previously had no broadband access because of its remote location.

- The launch is the second Starlink mission in less than two weeks as SpaceX seeks to maintain a rate of roughly two Starlink launches a month to build out the constellation. Those launches have moved ahead while another Falcon 9, carrying a GPS 3 navigation satellite for the U.S. Space Force, remains grounded after a last-second abort Oct. 2 blamed on a problem with gas generators in the rocket’s first-stage engines.

- That scrub led NASA to postpone a Falcon 9 launch of the Crew-1 commercial crew mission, which had been scheduled for Oct. 31. NASA announced Oct. 10 it was postponing the launch to the first half of November while the investigation into the scrub continues.

- NASA has not issued any updates on the status of the Crew-1 launch, although one NASA webpage lists a launch of no earlier than Nov. 11. “That investigation is ongoing,” Tim Dunn of NASA’s Launch Services Program said at an Oct. 16 briefing about the scheduled Nov. 10 launch of the Sentinel-6 Michael Freilich ocean science satellite, which will also use a Falcon 9.

- Dunn said that there has been a “tremendous amount of testing” since the GPS 3 launch scrub, including taking the Merlin engines from that rocket back to SpaceX’s McGregor, Texas, test site for further study. That investigation has involved NASA and Space Force personnel working with SpaceX.

- He did not elaborate, though, on the specific problem with the engines or when either the GPS 3 or Crew-1 missions might launch. “We’ve learned a lot. There’s going to be some hardware implications as we move forward, depending on the engines installed on various rockets,” he said.

- However, he did not expect the engine issue to delay the Sentinel-6 Michael Freilich launch. “As of today, we have a path forward that allows us to do whatever necessary rework may be required and still maintain that 10 November launch date.”


Launch12: Sixty more SpaceX Starlink broadband satellites rocketed into orbit on 6 October 2020 (11:29:34 UTC) from LC-39A at the Kennedy Space Center, breaking a streak canceled launch attempts at the Florida spaceport in recent weeks and nudging the Starlink network closer to reaching a wider population. 33)

- After 2.5 minutes, the first stage booster shut down and jettisoned to begin a descent toward SpaceX’s drone ship positioned in the Atlantic Ocean around 630 km northeast of Cape Canaveral.

- The Falcon 9’s first stage nailed the landing — the 61st successful recovery of a SpaceX rocket booster — as the second stage injected the mission’s 60 Starlink satellites into orbit.

- The reusable booster completed its third trip to space and back, following flights earlier this year to help send NASA astronauts Doug Hurley and Bob Behnken into orbit on a Crew Dragon capsule in May, and a launch in July with South Korea’s Anasis 2 military communications satellite.

- One half of the two-piece, clamshell-like payload fairing on this mission was also making its third flight. A recovery boat in the Atlantic caught the reusable fairing half again as it descended under a parachute.

- The Falcon 9’s upper stage ignited a second time to place the 60 Starlink payloads into an on-target near-circular orbit around 170 miles (275 km) above Earth, with an inclination of 53 degrees to the equator.

- The 60 flat-panel satellites separated from the Falcon 9’s upper stage around 12:31 GMT. A live video feed from the rocket showed the payloads drifting away into space.

- The 60 spacecraft, built by SpaceX in Redmond, Washington, were expected to unfurl solar panels and activate krypton ion thrusters to begin raising their altitude to 550 km, where they will begin providing broadband service.

- With this launch, SpaceX has deployed 775 Starlink satellites to date, including two prototype platforms and 773 satellites on 13 Falcon 9 launches since May 2019.

- SpaceX plans to operate an initial block of around 1,500 Starlink satellites in orbits 550 km above Earth. The company, founded by billionaire Elon Musk, has regulatory approval from the Federal Communications Commission to eventually field a fleet of up to 12,000 small Starlink broadband stations operating in Ku-band, Ka-band, and V-band frequencies.


Launch 11: The next 60 Starlink relay nodes blasted off on 3 September 2020 (Thursday, 12:46:14 GMT) from Cape Canaveral LC -39A on top of a Falcon 9 rocket, riding SpaceX’s workhorse launcher into orbit. 34)

- The Falcon 9’s reusable first stage booster landed on SpaceX’s drone ship “Of Course I Still Love You” holding position in the Atlantic Ocean a couple hundred miles east of Charleston, South Carolina.

- The propulsive pinpoint landing marked the 60th time SpaceX has recovered a Falcon 9 booster, and it completed the second trip to space and back for the specific rocket flown on Thursday.

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Figure 12: A Falcon 9 rocket lifts off from pad 39A of Cape Canaveral, Florida, with 60 more Starlink satellites (image credit: SpaceX)

- Meanwhile, the Falcon 9’s upper stage engine injected the 60 Starlink satellites into an on-target orbit tilted 53 degrees to the equator. Retention rods released to allow the flat-panel satellites to fly free of the Falcon 9 rocket around 15 minutes after liftoff.

- SpaceX declared success on the mission, which was the company’s second launch in less than four days from separate pads on Florida’s Space Coast.

- After their deployment from the Falcon 9 rocket, the Starlink satellites were expected to extend solar panels and activate krypton ion thrusters to begin raising their orbit to the Starlink network’s operational shell roughly 550 km above Earth.

- With the 60 fresh satellites launched today, SpaceX has delivered 713 Starlink satellites to orbit on 12 Falcon 9 rocket missions since May 2019. Some of the satellites, including those on the first Starlink launch last May, are being moved to lower altitudes and deorbited.

- SpaceX eventually plans to launch thousands of Starlink satellites, but the first tranche of Starlinks will number 1,440 spacecraft, according to Jonathan Hofeller, SpaceX’s vice president of Starlink and commercial sales.

- “The total global constellation we’re targeting is 1,440 satellites, of which a good number of those are already on orbit,” Hofeller said.

- Each flat-panel Starlink satellite has a mass of about 250 kg, and they are built at a SpaceX facility in Redmond, Washington, near Seattle. Extending on SpaceX’s penchant for building hardware in-house, the aerospace company is manufacturing its own Starlink satellites, user terminals and ground stations.

- Hofeller said last month that SpaceX is building six Starlink spacecraft per day, and plans to launch Starlink missions at intervals of every two to three weeks until completing the initial Starlink network of around 1,440 satellites.

- In a discussion at the ASCEND Space Science and Technology Summit last month, Hofeller said that the private beta testing is being rolled out in the Pacific Northwest. With roughly 700 satellites, the Starlink network has enough coverage to provide connectivity to users at high latitudes, but more launches are required to expand coverage to other regions.

- SpaceX has asked people interested in participating in the public beta test phase to sign up on the Starlink website.

- SpaceX said Thursday that the tests so far show the network has “super low latency” with download speeds greater than 100 Mbit/s. That’s fast enough to stream multiple HD movies at once, and still have bandwidth to spare, according to SpaceX.


Launch 10: A Falcon 9 rocket loaded with 58 more broadband relay nodes for SpaceX’s Starlink Internet network took off on 18 August 2020 (14:31:16 UTC) from Cape Canaveral LC40, bringing the total number of Starlink spacecraft launched since May 2019 to 653 satellites. 35)

- The reusable Falcon 9 booster that powered the 58 Starlink satellites toward space was making its sixth flight, setting a new record for SpaceX’s liquid-fueled rocket family.

- The fresh Starlink craft launched today widened SpaceX’s lead in fielding the largest fleet of satellites, and also added to the constellation of Earth-imaging satellites owned by Planet. Planet’s satellite fleet is the second-biggest after SpaceX’s Starlink network.

- Three commercial SkySat Earth observation satellites hitched a ride into orbit on the Falcon 9 rocket, joining around 150 other small spacecraft in the Planet’s fleet.

- Two-and-a-half minutes after liftoff, the Falcon 9’s first stage shut down its nine Merlin engines and separated to begin a descent toward SpaceX’s drone ship “Of Course I Still Love You” positioned in the Atlantic Ocean around 400 miles (630 km) northeast of Cape Canaveral.

- After ignition of the Falcon 9’s upper stage engine, the rocket shed its clamshell-like payload shroud at T+plus 3 minutes, 12 seconds. The two halves of the nose cone came back to Earth under parachutes for retrieval by a pair of SpaceX recovery boats.

- The 15 story first stage nailed its return to SpaceX’s offshore landing platform nearly nine minutes after liftoff, completing its sixth round-trip flight to space and back. That’s a new record for SpaceX’s fleet of Falcon boosters, which previously had flown no more than five times a piece.

- Designated B1049 in SpaceX’s fleet, the booster used on Tuesday’s mission first flew from Cape Canaveral in September 2018 in the launch of Telesat’s Telstar 18 VANTAGE communications satellites. After landing on a SpaceX drone ship, the booster launched again from California in January 2019 with 10 Iridium voice and data relay satellites, and again returned to a propulsive touchdown on an offshore recovery vessel.

- The Falcon first stage launched three more times with satellites for SpaceX’s Starlink broadband network, most recently on June 3. SpaceX says the Falcon 9’s first stage booster is capable of at least 10 flights without a major overhaul, though engineers perform routine inspections and refurbishment between each mission.

- SpaceX later confirmed one of the two halves of the payload shroud used on Tuesday’s launch was successfully caught by a net aboard one of the company’s two fairing recovery vessels. The other fairing clamshell parachuted into the Atlantic Ocean and will be retrieved for return to Cape Canaveral, SpaceX said. — The fairing on today’s mission was reused from a previous Falcon 9/Starlink launch.

- The Falcon 9’s upper stage delivered its 61 satellite passengers into an on-target elliptical orbit around Earth ranging in altitude between 128 miles (207 km) and 229 miles (370 km). The three SkySats, mounted on top of the Starlink satellite array, separated at 30-second intervals beginning about 12-and-a-half minutes into the mission.

- After flying halfway around the world, the upper stage released the 58 Starlink payloads over the Indian Ocean about 46 minutes after liftoff.

- Beginning with the Starlink launch earlier this month, SpaceX says all of the Starlink satellites are equipped with sunshade visors (see Figure 15) to reduce their reflectivity, a measure aimed at mitigating concerns that thousands of Starlink spacecraft might interfere with astronomical observations using ground-based telescopes.

- SpaceX’s Starlink network is designed to provide low-latency, high-speed Internet service around the world. Elon Musk, SpaceX’s founder and CEO, also views the Starlink program as a means to earn revenue to help fund the company’s lofty ambitions to develop a next-generation reusable rocket known as Starship, which Musk says could eventually carry people to the moon and Mars.

- SpaceX says it needs 24 launches to provide Starlink Internet coverage over nearly all of the populated world, and 12 launches could enable coverage of higher latitude regions, such as Canada and the northern United States.

- SkySats: The three Planet-owned Earth observation satellites deployed in orbit Tuesday are the last three of 21 SkySat high-resolution reconnaissance platforms the San Francisco-based company plans to launch.

- The SkySats join 18 others Planet has launched aboard U.S., European and Indian rockets since 2013, supplying regularly-updated sharp images of the world’s cities, forests, farms, waterways, and other regions of interest to government and commercial users.

- Planet confirmed its ground team acquired the first radio signals from all three satellites minutes after Tuesday’s launch, confirming the spacecraft were alive and well in orbit.

- The SkySats offer Planet’s customers high-resolution views of Earth, while a flock of more than 100 smaller Dove CubeSats provide wider area coverage at lower resolution.

- Planet launched three identical SkySats on a Falcon-9/Starlink launch June 13, and the three new spacecraft launched on 18 August will bring the SkySat fleet to 21 satellites.

- The SkySats taking off on rideshare missions with SpaceX’s Starlink satellites fly at a lower-inclination orbit inclined 53º to the equator. Planet says the new satellites “will offer more targeted coverage and raw image capacity in key geographic regions.”

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Figure 13: Three Planet SkySat Earth-imaging satellites (SkySat-19, -20 and -21) accompanied 58 SpaceX Starlink satellites on a Falcon-9 rocket on Launch 11 (image credit: SpaceX)


Launch 9: On 7 August 2020 (05:12:05:UTC), SpaceX launched their 10th Starlink mission, carrying 57 minisatellites and two commercial microsatellites of the BlackSky Global (a division of Spaceflight Industries) Earth observation constellation of Seattle WA, USA (BlackSky's fifth and sixth satellites - named Global 7 and 8, each with a mass of 55 kg). The launch site was LC-39A (Launch Complex 39A) at NASA’s Kennedy Space Center in Florida. The launch vehicle was Falcon-9. With this launch, SpaceX will have delivered 595 Starlink satellites to orbit since May 2019. 36) 37)

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Figure 14: BlackSky’s fifth and sixth operational Earth-imaging satellites are pictured inside a SpaceX processing facility at Cape Canaveral (image credit: SpaceX)

The mission was previously scheduled for 26 June, but the flight was scrubbed around three hours ahead of liftoff when SpaceX tweeted that they needed more time for pre-launch checkouts.

According to SpaceX, Falcon 9’s first stage previously supported Crew Dragon’s first demonstration mission to the International Space Station, the launch of the RCM (RADARSAT Constellation Mission), and the fourth and seventh Starlink missions.

Following stage separation, Falcon 9’s first stage landed on the “Of Course I Still Love You” droneship stationed in the Atlantic Ocean.

The BlackSky Global spacecraft deployed sequentially beginning 1 hour and 1 minute after liftoff, and the Starlink satellites deployed approximately 1 hour and 33 minutes after liftoff.

This is the first launch of SpaceX to carry a full set of Starlink satellites equipped with new sunshades, or visors, in an attempt to make the spacecraft less visible to ground-based telescopes, addressing concerns voiced by astronomers that thousands of Starlink satellites could interfere with scientific observations.

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Figure 15: SpaceX plans to debut a new sunshade structure on its future Starlink satellites (image credit: SpaceX)


Launch 8: On June 13, 2020 (9:21 UTC), SpaceX successfully launched their ninth Starlink mission, carrying 58 Starlink satellites and three of Planet’s SkySat Earth Observation microsatellites (110 kg each) from the Cape Canaveral Air Force Station in Florida — this mission marked SpaceX’s first SmallSat Rideshare Program launch. 38)

- SpaceX deployed the SkySat satellites first, about 13 minutes after liftoff, followed by the Starlink satellites about 39 minutes after liftoff.

- The mission used a Falcon 9 booster that flew two cargo missions to the International Space Station for NASA, the last being CRS-20 in March. The rocket featured a previously flown payload fairing, with one half recovered from the Jcsat-18/Kacific-1 satellite mission in December, and the other from SpaceX’s third Starlink mission, which took place in January.

- SpaceX recovered the rocket’s first-stage for a third time, landing the booster on the drone ship “Of Course I Still Love You” in the Atlantic Ocean.

- SpaceX Lead Manufacturing Engineer Jessie Anderson said the launch contract covering Planet’s three SkySat satellites was signed six months ago. Planet’s Saturday launch, and a second Starlink rideshare scheduled for July will complete the operator’s constellation of 21 SkySats, a fleet that complements Planet’s larger constellation of Dove CubeSats.

- Once all 21 SkySats are in orbit, Planet says it will be able to image locations an average of seven times a day, with some locations seeing up to 12 revisits a day, at 50-centimeter resolution. Planet’s CubeSats collect imagery in 3-5 meter resolution.

- Another Earth-observation company, BlackSky, said in a recent interview that it has two satellites scheduled to launch June 24 on a Starlink rideshare mission. Barring schedule slips, that would be three Starlink launches in June, which would be the highest number of Starlink launches conducted in a month.

- SpaceX was targeting two Starlink launches a month throughout 2020, but has averaged one Starlink launch a month so far. The company has launched 540 Starlink satellites to date, counting two prototypes, out of a planned system comprising several thousand.

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Figure 16: Three of Planet’s SkySat Earth-imaging microsatellites are mounted on top of 58 SpaceX Starlink Internet satellites for launch on 13 June 2020 (image credit: Planet / SpaceX)


Launch 7: On June 4 2020 (01:25 UTC, or at 9:25 pm EDT on June 3), SpaceX launched the eighth batch of Starlink communication satellites on a flight-proven Falcon 9 rocket from Cape Canaveral’s Space Launch Complex 40 (LC-40). The successful launch boosted the number of Starlink satellites circling the Earth to 480, by far the greatest number of any communications network. 39)

- At about 2 minutes, 45 seconds after launch, the nine main engines of the rocket's first stage shut off, and that stage re-entered the Earth's atmosphere for recovery off Florida on the SpaceX barge named Just Read the Instructions. - The first stage landed mostly inside a bull's-eye on the flat deck.

- The second stage carried the satellites into orbit successfully, SpaceX engineers said. Video showed the Starlink cluster deploying roughly 15 minutes after liftoff.

- The size of the Starlink constellation already is large enough for "minor" Internet coverage around the world, according to SpaceX founder Elon Musk's statements to the press before the first Starlink launch in 2019.

- But SpaceX hasn't released more information about the network's operation or its intended customers.

- Starlink aims to provide next-generation broadband Internet service to the globe, outpacing that offered by such players as Iridium or Intelsat. SpaceX said in 2019 it aimed to launch 1,600 satellites in the first phase.

- At that point, the satellites would transmit data to each other via laser pulses through the vacuum of space — a far faster method than even fiber optic cables on Earth.

- Starlink, which the company said could cost $10 billion to develop and launch, has boosted the value of SpaceX and its recent rounds of investment, according to stock analysts and SpaceX's filings with the Securities and Exchange Commission.

- SpaceX raised $567 million, according to the commission documents filed in the last few months.

- "We are modeling for $10 billion to $15 billion from 2020-2025 for Starlink, with the potential for more from ground terminals, 30,000 additional satellites and replacement of satellites" and other SpaceX endeavors, according to a recent note from analysts at Morgan Stanley.

- Starlink also would owe some of its speed to its much lower orbit than previous communication satellite networks — 340 miles (550 km) up.

- By comparison, Iridium satellites are about 485 miles (780 km ) up. The Kármán line that defines space is 62 miles high, and the International Space Station is more than 250 miles (400 km) high.

- On this mission, SpaceX was to launch the first Starlink satellite with a visor to block sunlight from hitting the brightest spots of the spacecraft. Musk announced April 27 that the sunshade, which he called a VisorSat, would be included in the next Starlink launch.

- VisorSat is designed to prevent the satellites from reflecting sunlight back to the Earth, which can interrupt astronomy observations.

- This was the second Starlink launch during restrictions on access to the Air Force station due to the coronavirus pandemic. The launch also came on the heels of Saturday's (31 May) successful SpaceX launch of the first flight of NASA astronauts from U.S. soil since 2011.

- The first-stage booster for this launch previously flew four times, including the launch of an Iridium satellite in January 2019, and two separate Starlink missions in May 2019 and January 2020.


Launch 6: On 22 April 2020 (19:30: 30 UTC), SpaceX launched 60 more Starlink satellites from Launch Complex 39A (LC-39A) at NASA’s Kennedy Space Center in Florida. 40)

Two-and-a-half minutes after liftoff, the Falcon 9’s first stage booster shut down and separated to begin a controlled descent back into the atmosphere. The rocket’s single-engine upper stage ignited seconds later, and the Falcon 9 released its clamshell-like payload fairing more than three minutes into the mission.

Flying into space for the fourth time, the reusable first stage nailed a pinpoint landing on SpaceX’s drone ship in the Atlantic Ocean east of Charleston, South Carolina. Two recovery ships were stationed in the Atlantic to retrieve the rocket’s two-piece payload shroud, which was also recycled from a previous flight.

The Falcon 9 rocket released retention rods holding the Starlink satellites to the upper stage around 15 minutes after launch. Video from camera on the rocket showed the 60 flat-panel satellites — each with mass of about a quarter-ton — receding into space over the North Atlantic Ocean.

The satellites were each expected to extend their power-generating solar panel wing go through an activation sequence. Krypton ion thrusters on the spacecraft will boost them from their preliminary elliptical transfer orbit to an operational altitude of 550 km over the coming weeks and months.

With this launch, SpaceX has delivered 422 Starlink satellites to space, including two prototypes that are now being deorbited. Since last May, SpaceX has orbited 420 Starlink spacecraft. Three of those relay stations are no longer in orbit, according to publicly-available U.S. military tracking data.


Launch 5: SpaceX launched their 6th Starlink mission of 60 satellites on March 18, 2020 (12:16 UTC). The company's Falcon 9 launch vehicle lifted off from Launch Complex 39A (LC-39A) at NASA’s Kennedy Space Center in Florida. 41) 42)

Falcon 9’s first stage previously supported the Iridium-7 NEXT mission in July of 2018, the SAOCOM 1A mission in October of 2018, the Nusantara Satu mission in February of 2019, and the second launch of Starlink in November of 2019. Falcon 9’s fairing previously supported the first launch of Starlink in May 2019.

he Starlink satellites deployed in an elliptical orbit approximately 15 minutes after liftoff. Prior to orbit raise, SpaceX engineers conducted data reviews to ensure all Starlink satellites are operating as intended. Once the checkouts are complete, the satellites will then use their onboard ion thrusters to move into their intended orbits and an operational altitude of 550 km.

An attempt to land the Falcon 9's first stage in the Atlantic Ocean on SpaceX's drone ship "Of Course I Still Love You" was unsuccessful.

And despite the loss of one of its nine engines, SpaceX CEO Elon Musk said they were still able to deliver the 60 Starlink satellites on board the Falcon 9, which went exactly as planned. That’s due in part to the redundancy built into the design of the Falcon 9 launch vehicle, which uses nine Merlin engines working together.


Launch 4: On February 17, 2020 (15:06 GMT), 60 more satellites for SpaceX’s Starlink broadband network launched Monday on a Falcon 9 rocket from Cape Canaveral, bringing the total number of Starlink platforms deployed in orbit since last May to 300. 43)

Two-and-a-half minutes into the mission, the Falcon 9’s first stage booster shut down its engines and separated, allowing a single Merlin engine on the launcher’s second stage to fire into orbit.

Seconds later, the Falcon 9’s payload shroud jettisoned as the rocket soared into space, revealing the launcher’s more than 15.6-metric ton payload package, comprised of 60 flat-panel signal relay nodes for SpaceX’s Starlink network.

While the second stage accelerated into orbit, the first stage of the Falcon 9 descended back through the atmosphere and attempted landing on SpaceX’s football field-sized drone ship “Of Course I Still Love You” holding position nearly 630 km northeast of Cape Canaveral.

But the rocket missed the drone ship and appeared to make a soft landing in the water nearby, according to streaming video from the offshore vessel. The missed landing marked the first time a first stage booster on a Falcon 9 rocket has missed a landing attempt on a SpaceX drone ship since 2016.

The Falcon rocket used on Monday’s mission was a veteran of three previous launches and landings. It’s not likely to be reused after landing in sea water.

Two other SpaceX vessels were positioned in the Atlantic Ocean to try to catch the two halves of the Falcon 9’s payload shroud. SpaceX did not announce the results of the fairing recovery attempt, but a company employee said engineers are still experimenting with catching the aerodynamic shroud using fast-moving ships fitted with giant nets. Previous catch attempts have been hit or miss.

Around the same time as the first stage reached the ocean, a SpaceX launch controller announced that the Falcon 9 upper stage had arrived in orbit and was poised to release the 60 Starlink satellites, the mission’s primary objective.

After firing thrusters to enter a controlled spin, the upper stage released retention rods holding the Starlink satellites to the rocket. That allowed the spacecraft to fly away from the Falcon 9 as the vehicles soared over the North Atlantic Ocean.

One change introduced Monday different from past Starlink missions was the release of the Starlink payloads into an elliptical transfer orbit, instead of a circular orbit.

“We are executing a direct inject of the Starlink satellites into an elliptical orbit,” said Jessica Anderson, a manufacturing engineer at SpaceX. “In prior Starlink missions, we deployed the satellites into a 290-kilometer circular orbit, which required two burns of the Merlin vacuum engine on the second stage.

“Keep in mind the stack of 60 Starlink satellites combined is one of the heaviest payloads we fly, so putting them directly into this orbit requires more vehicle performance and makes recovery more challenging,” she said. “Going forward, and starting with today, we will deploy the satellites shortly after the first burn of the second stage, putting the Starlink satellites into an elliptical orbit.

“Once checkouts are complete, the satellites will then use their on-board ion thrusters to move into their intended orbits at an operational altitude of 550 km.”

According to preflight predictions, the Starlink craft on Monday were programmed for deployment in an elliptical, or egg-shaped, orbit ranging between 212 and 386 kilometers in altitude, with an inclination of 53º to the equator.

As a result of the orbit change, the Falcon 9’s second stage remained in orbit after release the Starlink satellites Monday. It is expected to passively re-enter the atmosphere in the coming months, instead of performing a controlled de-orbit burn, as the stage did after previous Starlink launches.

Like SpaceX’s previous Starlink launches, the satellites deployed in a tight cluster. SpaceX ground teams will activate krypton ion thrusters and other systems on the satellites to maneuver them into a higher orbit, targeting an altitude of 341 miles (578 km) for operational service broadcasting signals in Ku-band.

The first phase of SpaceX’s Starlink program, which aims to beam consumer broadband to customers around the world, will include 1,584 of the flat-panel satellites — including spares — in orbit 578 km above Earth.

SpaceX has approval from the Federal Communications Commission to operate nearly 12,000 Starlink satellites in Ku-band, Ka-band and V-band frequencies, with groups of spacecraft flying at different altitudes with various orbital inclinations.


Launch 3: On January 29, 2020, SpaceX launched a Falcon 9 rocket carrying it's third batch of 60 Starlink satellites. The launch was at 9:06 a.m EST (14:06 GMT) Wednesday from Cape Canaveral Air Force Station, Fla. Two-and-a-half minutes after liftoff, the rocket’s first stage shut down its engines and dropped away from the Falcon 9’s second stage. Seconds later, the upper stage’s single Merlin engine — modified with an enlarged nozzle for better performance in space — ignited to accelerate the 60 Starlink satellites into orbit. 44)

The Falcon 9 jettisoned its clamshell-like payload fairing nearly three-and-a-half minutes into the mission.

Flying tail first, the rocket’s first stage booster reignited three of its nine engines to guide it toward SpaceX’s drone ship “Of Course I Still Love You” positioned around 630 km northeast of Cape Canaveral. A final landing burn using the center engine slowed the booster for a controlled vertical touchdown on the football field-sized barge, marking the 49th time SpaceX has recovered one of its rockets intact.

The booster flown Wednesday was making its third trip to space, following successful launches and landings in March 2019 and June 2019 on flights carrying SpaceX’s Crew Dragon spacecraft and Canada’s Radarsat Constellation Mission. With Wednesday’s mission, the booster has launched from all three of SpaceX’s active launch pads in Florida and California.

SpaceX said the rocket did its job placing the satellites into the proper orbit, and live video from the Falcon 9’s second stage showed the 60 flat-panel satellites separating from the launch vehicle as it flew south of Australia about one hour after liftoff from Cape Canaveral.

The spacecraft were expected to extend their power-generating solar panels, and krypton ion thrusters on each satellite will begin raising their orbits to an altitude of around 550 km, where SpaceX intends to operate its first 1,584 Starlink platforms to provide worldwide Internet service.

The Starlink satellites, built at a SpaceX facility in Redmond, Washington, filled the volume of the Falcon 9’s payload fairing. Each satellite has a mass of 260 kg, and the Starlink spacecraft stacked together form the heaviest payload SpaceX has ever launched.

With Wednesday’s launch, SpaceX has deployed 240 Starlink satellites on four dedicated missions since last May. That makes SpaceX the owner of the world’s largest fleet of commercial satellites.

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Figure 17: A view of the 60 Starlink satellites stacked before Wednesday’s launch (image credit: SpaceX)

SpaceX says 24 launches are needed to provide global broadband service through the Starlink service. But the company could provide an interim level of service over parts of the Earth later this year, once SpaceX has launched around 720 satellites on 12 Falcon 9 flights.


Launch 2: On 7 January 2020 (02:19 UTC), SpaceX launched its third batch of 60 Starlink minisatellites (Starlink V1.0-L2) into orbit on a Falcon-9 Block 5 vehicle from Cape Canaveral SLC-40. 45)

- The launch of 60 more spacecraft for the Starlink project, which SpaceX sees as a core business area in the coming years, makes the company the operator of the largest fleet of commercial satellites, surpassing the previous mark set by Planet, an operator of Earth-imaging nanosatellites.

- SpaceX wants to begin limited Internet service through the Starlink network later this year, then expand to global service to beam Internet signals to consumers in far-flung locales outside the reach of terrestrial wired broadband connections. Users on airplanes, ships and the U.S. military could also be Starlink customers.

- Blazing a similar trail to two previous Starlink satellite launches last year, a SpaceX Falcon 9 rocket lifted off from pad 40 at Cape Canaveral at 9:19:21 p.m. EST Monday (02:19:21 GMT on 7 January) and turned on a northeasterly heading over the Atlantic Ocean.

- Nine kerosene-fueled Merlin 1D engines on the base of the first stage powered the rocket off the launch pad with 1.7 million pounds of thrust.

- After two-and-a-half minutes, the nine main engines shut down and the first stage separated to begin descent maneuvers toward a landing on SpaceX’s drone ship “Of Course I Still Love You” in the Atlantic Ocean.

- The first stage — flying for the fourth time on Monday night’s mission — nailed its landing on the drone ship, marking the 48th time SpaceX has successfully landed a Falcon booster since the company’s first rocket recovery in 2015. An attempt to catch one half of the Falcon 9’s clamshell-like payload fairing in a net fastened to an ocean-going vessel was unsuccessful, SpaceX said.

- The Falcon 9’s second stage ignited its Merlin engine two times to place the 60 Starlink satellites into an orbit with a target altitude of 180 miles (290 kilometers) and an inclination of 53 degrees to the equator. SpaceX confirmed the Falcon 9 injected the payloads close to the planned orbit.

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Figure 18: SpaceX’s Falcon 9 rocket streaks downrange to the northeast from Cape Canaveral Monday night with 60 Starlink satellites for the company’s planned global Internet network (image credit: SpaceX)


Launch 1: Sixty upgraded satellites for SpaceX’s Starlink broadband network (Starlink V1.0-L1) rocketed into orbit on Monday,11 November 2019 (14:56 UTC) from Florida’s Space Coast (SLC-40), debuting performance enhancements and notching new firsts in SpaceX’s list of rocket reuse accomplishments. 46)

- SpaceX’s second batch of Starlink satellites joined 60 previous broadband-beaming spacecraft in orbit after deployment from a Falcon 9 rocket, adding to a network that may eventually include thousands of satellites broadcasting high-speed Internet signals from space.

- The 70 m Falcon 9 climbed away from Cape Canaveral’s Complex 40 launch pad at 9:56 a.m. EST (14:56 GMT), turned toward the northeast and soared through scattered clouds on a gorgeous Veterans Day morning.

- The Falcon 9’s first stage shut down and detached from the rocket’s second stage around two-and-a-half minutes into the flight. Moments later, the Falcon 9’s second stage lit its single Merlin powerplant to propel itself into orbit with the Starlink payloads, then the rocket’s nose cone opened and fell away, revealing the Starlink satellites after transiting through the thick, lower layers of the atmosphere.

- The first stage booster returned to a propulsive landing on SpaceX’s drone ship “Of Course I Still Love You” holding position around 250 miles downrange from Cape Canaveral in the Atlantic Ocean, roughly due east of Charleston, South Carolina. The rocket completed its fourth mission, following three previous launches and landings — two last year, and one in February that helped loft into space an Indonesian communications satellite and the Israeli Beresheet moon lander.

- This launch was the first time SpaceX flew a Falcon 9 booster on a fourth mission. It also marked another first for SpaceX, which demonstrated its capability to reuse a payload fairing recovered from a previous launch.

- The bulbous payload shroud protects satellites during the first few minutes of flight, then drops away from the rocket in two halves. The fairing halves flown on 11 November originally launched on a Falcon Heavy mission April 11, then parachuted into the Atlantic Ocean, where SpaceX teams pulled them from the sea for inspections, refurbishment and reuse.

- Pursuing the prime objective of Monday’s mission, the Falcon 9’s second stage engine switched off about nine minutes after launch, and the rocket coasted over Europe and the Middle East before reigniting its engine at around 10:41 a.m. EST (15:41 GMT) to circularize its orbit. The Falcon 9 aimed for an altitude of around 174 miles (280 km) for deployment of the Starlink satellites, and a member of SpaceX’s launch team confirmed the rocket achieved an on-target orbit.

- The Falcon 9 sent commands at 10:56 a.m. EST (15:46 GMT) to release retention pins holding the Starlink satellites to the launcher, and live video from a camera on-board the rocket showed the 60 flat-panel spacecraft receding in the blackness of space.

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Figure 19: Sixty Starlink satellites separated from the Falcon 9 rocket about one hour after launch Monday. The spacecraft deployed in one piece, then will disperse over the coming hours and days (image credit: SpaceX)

- The satellites, monitored at the SpaceX Control Center facility in Redmond, Washington, are designed to gradually disperse over the coming hours and days. Ion thrusters fed by krypton fuel will maneuver the satellites into their orbits at an altitude of 550 km with an inclination of 53º.

- SpaceX says 1,440 of the satellites are needed to provide Internet service over the “populated world,” a service level the company says could be achieved after 24 launches.

- The Starlink network could offer service for northern parts of the United States and Canada after six launches, according to SpaceX.

- SpaceX could launch thousands more Starlink satellites if merited by market demand. The Federal Communications Commission has authorized SpaceX to operate nearly 12,000 Starlink satellites broadcasting in Ku-band, Ka-band and V-band frequencies, with groups of spacecraft positioned at different altitudes and in various planes in low Earth orbit.

- The Starlink network is rapidly becoming a core business area for SpaceX, which is competing with companies like OneWeb and Amazon’s Project Kuiper to deploy fleets of thousands of small satellites in low Earth orbit to beam broadband Internet signals from space to users around the world.

- Developers of the so-called “mega-constellations” in low Earth orbit say their networks offer key advantages over traditional satellite Internet architectures, which relay on satellites in higher orbits, where radio transmissions — even traveling at the speed of light — take longer to reach.

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Figure 20: Artist’s illustration of the distribution of satellites in SpaceX’s Starlink network (image credit: SpaceX)

- “Since the most recent launch of Starlink satellites in May, SpaceX has increased spectrum capacity for the end user through upgrades in design that maximize the use of both Ka- and Ku-bands,” SpaceX wrote in a press kit for Monday’s launch. “Additionally, components of each satellite are 100% demisable and will quickly burn up in Earth’s atmosphere at the end of their life cycle — a measure that exceeds all current safety standards.”

- SpaceX said the new Starlink spacecraft design can provide a 400 percent increase in data throughout per satellite, and each satellite carries double the number of steerable phased array broadband beams than on earlier Starlink platforms.

- The first 60 Starlink satellites, which launched May 23, carried only Ku-band antennas. At the time, SpaceX said 95 percent of the materials in each of the first 60 satellites would burn up in the atmosphere after their missions were complete.

- Gwynne Shotwell, SpaceX’s president and chief operating officer, said last month that the company plans to begin launching Starlink spacecraft equipped with inter-satellite laser crosslinks some time mid-to-late next year.

- Three of the 60 satellites launched in May have stopped communicating with ground controllers, but SpaceX officials say they are pleased with the overall performance of the initial block of Starlink spacecraft.

- The U.S. Air Force is testing Internet connections between aircraft and SpaceX’s Starlink satellites to evaluate the network’s suitability for future military use, and Elon Musk, SpaceX’s founder and CEO, said he sent a tweet last month through a Starlink satellite.

- “We still have ways to go from tweets to 4K cat videos, but we are on our way,” joked Lauren Lyons, a SpaceX engineer who hosted the company’s webcast of Monday’s launch.


Launch : The first demonstation flight of SpaceX's Starlink satellite constellation launched on 24 May ,2019 (02:30 UTC) with the twice-flown Falcon-9 rocket from SLC-40 (Space Launch Complex-40) at Cape Canaveral Air Force Station, Florida. The Falcon vehicle contained a payload of 60 minisatellites, each with a mass of 227 kg. 47) 48)

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Figure 21: Image of the first launch of SpaceX's Starlink satellite constellation on 24 May 2019 at 2:30 UTC (image credit: Satnews Daily)

Today’s launch is a major step towards the final goal of launching and operating 12,000 satellites in orbit to beam internet to the ground by the 2020s, reaching those who are not yet connected, with reliable and affordable broadband internet services. It’s estimated that 4 billion people in the world remain unconnected to the internet.

Eight minutes after the launch, the first stage of the rocket successfully landed on the drone ship Of Course I Still Love You (OCISLY) in the Atlantic Ocean. This was the third flight for the first stage booster, having flown on the Telstar 18 VANTAGE mission in September 2018, and the Iridium-8 mission in January 2019.

With a flat-panel design featuring multiple high-throughput antennas and a single solar array, each Starlink satellite has a mass of ~227 kg, this is SpaceX’s heaviest launch to date at about 13,620 kg, thus allowing SpaceX to maximize mass production and take full advantage of Falcon- 9’s launch capabilities. To adjust position on orbit, maintain intended altitude, and deorbit, Starlink satellites feature Hall thrusters powered by krypton.

An hour later, the Falcon-9 rocket began to release the satellites at an altitude of 450 km. The satellites then had to separate and use their thrusters to take up their positions in a relatively low orbit of 550 km. 49)

"Successful deployment of 60 Starlink satellites confirmed!", the company said on its official Twitter account.


Minimize Starlink continued


Mission status

• March 8, 2021: SpaceX is seeking regulatory permission to connect moving vehicles to its rapidly expanding Starlink constellation, branching the broadband network out of fixed homes and offices. 50)

- The company is asking the FCC (Federal Communications Commission) for authorization similar to the blanket license it already has for up to a million end-user customer Earth stations.

- David Goldman, SpaceX’s director of satellite policy, said in a regulatory filing that its Earth Stations in Motion (ESIM) equipment is “electrically identical to its previously authorized consumer user terminals but have mountings that allow them to be installed on vehicles, vessels and aircraft, which are suitable for those environments.”

- SpaceX recently told the FCC it has more than 10,000 Starlink users in the United States and abroad, after launching more than 1,100 high-speed internet satellites.

- The possibility of diversifying into more markets will raise eyebrows in the satellite mobility industry, as Elon Musk’s launch company continues to raise sizable funding rounds to back its capital-intensive plans.

- Satellite operators Inmarsat, SES and Intelsat are among those likely to feel the most disruption in the land-mobile market, Northern Sky Research principal analyst Brad Grady said.

- Depending on the exact form factors and use cases, Grady said mobile-satellites service (MSS) businesses at Inmarsat and Iridium Communications might see disruption akin to when maritime products transitioned to VSATs (Very-Small-Aperture Terminals).

- However, antenna maker Kymeta and other players in the communications on the pause (COTP) market segment are likely to feel more of an impact from early Starlink adoption.

- “Right now, there really isn’t a high-bandwidth/low latency form factor solution for that market segment that would match the terminal form factor of Starlink,” Grady said.

- “Perhaps once [SES’ next-generation constellation] mPower and their terminal segment develops in the next couple of years we’ll see another competitor there, but the COTP market is a far easier nut to crack in my view.”

- Almost all other non-GEO high-throughput satellite (HTS) constellations have been diversifying into other markets, and Grady said investors and industry have already “priced-in” Starlink as a competitive threat, potential partner or solution as they prepare for its eventual entrance.

- Starlink is likely eying opportunities at Tesla, Musk’s electric vehicle and energy company, which makes cars that currently rely on terrestrial telecoms companies for connectivity.

- Last year, SpaceX sought FCC permission to test Starlink services on private jets, as well as the vessels its rockets land on for reuse.

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Figure 22: Starlink's $499 self-install starter kit includes a phased array antenna that industry veterans say likely costs SpaceX $1,000 or more to manufacture (image credit: SpaceX)

• February 19, 2021: To realize his dream of satellite-powered internet, tech billionaire Elon Musk needs to install antennas around the world. In northern France, a village hopes he'll decide to keep those antennas far away. 51)

- Saint-Senier-de-Beuvron, population 350, is none too thrilled to have been picked as a ground station for Musk's Starlink project for broadband from space.

- "This project is totally new. We don't have any idea of the impact of these signals," said Noemie Brault, a 34-year-old deputy mayor of the village just 20 km (12 miles) from the majestic Mont Saint-Michel abbey on the English Channel.

- "As a precaution the municipal council said no," she explained.

- Musk, founder of SpaceX and electric carmaker Tesla, plans to deploy thousands of satellites to provide fast internet for remote areas anywhere in the world.

- It's a high-stakes battle he is waging with fellow billionaire Jeff Bezos of Amazon as well as the London-based start-up OneWeb.

- Antennas on the ground will capture the signals and relay them to individual user terminals connected by cable.

- Starlink's contractor had already secured French regulatory approval to install nine "radomes" — three-meter-tall globes protecting the antennas — in Saint-Senier, one of four sites planned for France.

- In December, Saint-Senier issued a decree to block construction on the field.

- But the refusal was based on a technicality, and the contractor, Sipartech, told AFP (Agence France Presse) that it plans to refile its request, which the council will likely be unable to block.

- "That worries us because we have no data" on the eventual effects of the signals on the health of humans or animals, said Brault, herself a farmer.

- "And when you hear that he wants to implant a chip in people's brains, it's frightening," she said, referring to Musk's Neuralink project.

- 'Not technophobes'

- Francois Dufour, a Greens council member and retired farmer, said he believes residents had reason to worry.

- "The risks from electromagnetic waves is something we've already seen with high-voltage power lines, which have disturbed lots of farmers in the area," he said.

- Besides, "social networks, internet, they exist already — why do we need to go look for internet on the moon?" he said.

- France's national radio frequency agency ANFR, which approved Starlink's stations, says they present no risks to residents, not least because they will be emitting straight up into the sky.

- There are already around 100 similar sites across France dating from the first satellite launches from 50 years ago, it adds.

- That hasn't convinced Jean-Marc Belloir, 57, who worries that his cows will start producing less milk.

- "On our farm, we're always online. My cows are linked up; my smart watch warns me when they're going to calve," Belloir said. "But when you see the range of these antennas, there has to be some research" on the potential impacts.

- Still, he baptized his latest calf "SpaceX du Beuvron," combining Musk's firm with the name of the creek that runs through his village.

- "We're not attacking Elon Musk," said Anne-Marie Falguieres, who lives just 60 meters from the future Starlink station with her husband and two children.

- "We're not technophobes. I'm a guide on the bay, I have an internet site, my husband works from home. But these antennas are completely new, at least in France, and we want to know if they're dangerous or not," she said.

- She also thinks the project is hardly necessary and unlikely to interest many, based on reports from the US.

- "In the testing phase, they made you pay $500 for the dish and then you had to pay $100 a month for a subscription," she said. "I don't think everyone's going to be able to pay that."

• February 4, 2021: SpaceX disclosed in a public filing on Thursday that its Starlink satellite internet service now has “over 10,000 users in the United States and abroad.” 52)

- “Starlink’s performance is not theoretical or experimental ... [and] is rapidly accelerating in real time as part of its public beta program,” SpaceX wrote in a filing with the Federal Communications Commission.

- Elon Musk’s company began a public beta program of Starlink in October, with service priced at $99 a month, in addition to a $499 upfront cost to order the Starlink Kit, which includes a user terminal and Wi-Fi router to connect to the satellites.

- The company is offering the service to select customers in the northern U.S., Canada, and the U.K.

- Starlink is SpaceX’s ambitious project to build an interconnected internet network with thousands of satellites, known in the space industry as a constellation, designed to deliver high-speed internet to consumers anywhere on the planet. The FCC two years ago approved SpaceX to launch 11,943 satellites, with the company aiming to deploy 4,425 satellites in orbit by 2024.

- SpaceX noted in the filing that Starlink’s service is “meeting and exceeding 100/20 Mbit/s throughput to individual users,” while the vast majority of users were seeing latency “at or below 31 milliseconds.”

- The update on Starlink’s customer base came in a petition to the FCC, with SpaceX asking that Starlink be designated an “Eligible Telecommunications Carrier” or ETC.

- The company noted that receiving this designation is necessary for Starlink to provide service to regions in “Alabama, Connecticut, New Hampshire, New York, Tennessee, Virginia and West Virginia.”

- SpaceX was awarded access to those regions under the FCC’s Rural Digital Opportunities Fund, an auction to bring broadband services to rural areas.

- The FCC in December awarded SpaceX with nearly $900 million in federal subsidies in the first phase of the auction.

- “Designating Starlink Services as an ETC is in the public interest because it will enable the company to receive support that will facilitate rapid deployment of broadband and voice service to the Service Areas at speeds and latency comparable to terrestrial systems in urban locations,” SpaceX wrote in the filing on Thursday.

- “Starlink Services respectfully requests that the Commission grant this petition by June 7, 2021 in order for Starlink Services to meet the Commission’s deadline for ETC designation for the purposes of receiving RDOF support.”

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Figure 23: A Starlink user terminal installed on the roof of a building in Canada (image credit: SpaceX)

- SpaceX’s rapid Starlink user growth is notable given the service has been in a public beta for just over three months.

- But customer demand was apparent before Starlink began offering early access, as SpaceX said in July that it received interest in the service from “nearly 700,000 individuals” across the United States. Those individuals’ interest came within the first two months of SpaceX allowing potential customers to sign up on the company’s website for updates on service availability.

• January 18, 2021: The German Astronomical Society (AG), the German association of amateur astronomers (VdS) and the Society of German-Speaking Planetariums (GDP) comment on the rapid increase in the number of satellites in the night sky. Artificial satellites have significant impact on the perception of the natural starry sky and the exploration of our universe. 53)

- Astronomical research institutes, observatories and planetariums have received a large number of concerned inquiries in recent months. The reason for this is the many satellites launched into Earth orbit by the private US space company SpaceX since May 2019, which are moving across the sky in groups.

- With Starlink, SpaceX hopes to provide a satellite-based network of high-speed internet connections worldwide. The final constellation will consist of more than 30,000 satellites, which far exceeds the number of all satellites in Earth orbit to date. Other companies such as OneWeb, Amazon and others are planning or in some cases already enacting similar projects. German companies also have corresponding plans to launch large numbers of microsatellites cheaply into Earth orbits. Astronomy is aware of the importance of connecting remote regions of the Earth to the internet, as well as other technological developments. Nevertheless, implementation via the enormous increase in artificial satellites in the sky also entails considerable restrictions and risks, the consequences of which must be weighed responsibly and reduced as far as possible.

- For astronomers, the protection of the night sky as a unique cultural heritage of mankind is a central concern. The experience of this natural wonder is already severely impaired in large parts of the world by inefficient and excessive artificial lighting. An uninterrupted view of the starry sky will no longer be possible due to the large number of light-reflecting artificial satellites, even in regions of the Earth that have so far been largely untroubled by light pollution. Even before the launch of the first Starlink satellites, numerous artificial satellites were observable in the night sky. With tens of thousands of additional objects orbiting the Earth, it is a realistic scenario that several thousand satellites passing over the firmament will obstruct stargazing in the night sky. Their number would then exceed that of the stars visible to the naked eye.

- This will forever change the night sky, the sight of which has fascinated and inspired mankind since the beginning. In addition, the exploration of the universe for professional and amateur astronomy will be significantly affected. Images of night landscapes and celestial objects, which have always carried the fascination of astronomy to the general public and contributed to general education, will be significantly affected. Astronomy forms the basis for our exploration and use of space. With the development of sophisticated observatories, many advances have been made in the exploration of our universe. Modern telescopes scan the sky and peer into the depths of space, furthering our understanding of the universe. However, these observations are significantly threatened by the multitude of satellites. Of particular note are studies of the dynamic universe. Optical telescopes for wide-field imaging will be impacted (such as the future Vera C. Rubin Observatory), as well as the tracking and monitoring of small bodies in the solar system that could potentially collide with Earth. In addition to optical astronomy, observations in infrared and radio wavebands from space will also be significantly affected.

- Radio astronomy is already increasingly disturbed by man-made signals, for example by the steadily growing volume of mobile communications. Therefore, scientists set up their observatories in very remote areas. However, the expected large number of satellites will operate around the globe so there will be no escape for radio astronomy either. German researchers do not only operate Europe’s largest radiotelescope, the 100-m telescope at Effelsberg near Bonn, but they are also involved in a large number of state-of-the-art radio observatories around the world, such as the Atacama Large Millimeter Array (ALMA) and the Square Kilometer Array (SKA) under construction in Australia and South Africa. These sites will then also be affected.

- The current development also poses a threat to manned and unmanned space flight, as it inevitably increases the risk of collisions.

- The degradation of the night sky has a global impact, but the approval of satellite launches is done exclusively by national authorities, such as the Federal Communications Commission in the US. We hereby express our concern about this and call for international regulations for satellite constellations to ensure the protection of the night sky over the entire electromagnetic spectrum for research and as a human cultural asset.

• January 9, 2021: The FCC (Federal Communications Commission) will allow SpaceX to launch 10 Starlink satellites into polar orbit on an upcoming mission, but deferred a decision on a much broader modification of SpaceX’s license. 54)

- In an order published Jan. 8, the FCC granted SpaceX permission to launch 10 Starlink satellites into a 560-kilometer orbit with an inclination of 97.6 degrees. Those satellites will launch on a Falcon 9 no earlier than Jan. 14 as part of Transporter-1, a dedicated smallsat rideshare mission.

- SpaceX had been lobbying the FCC for weeks for permission to launch Starlink satellites into a polar orbital plane as the FCC considers a modification of the company’s license to lower the orbits of satellites originally authorized for higher altitudes. That included a Nov. 17 request to launch 58 satellites into a single polar orbital plane, citing “an opportunity for a polar launch in December” that it did not identify.

- In a Jan. 5 filing with the FCC, SpaceX said it spoke with FCC officials the previous day about this request. “SpaceX confirmed that if it receives the proper authorization, its forthcoming Transporter-1 mission will include 10 Starlink satellites targeted for operation in polar orbits,” the company stated.

- SpaceX argued in filings that adding at least some satellites into polar orbits would allow it to begin service in Alaska, which is not in the coverage area of existing Starlink satellites launched into mid-inclination orbits. The company said in its November filing that “launching to polar orbits will enable SpaceX to bring the same high-quality broadband service to the most remote areas of Alaska that other Americans have come to depend upon, especially as the pandemic limits opportunities for in-person contact.”

- Other satellite operators opposed the move. In a Nov. 19 filing, Viasat said that “commercial expediency” was not a sufficient reason for the FCC to grant SpaceX permission for launching satellites into polar orbit, raising concerns about the reliability of Starlink satellites and the orbital debris hazards they pose.

- The FCC, in its order, concluded that allowing SpaceX to launch the 10 Starlink satellites into polar orbits was in the public interest. “We find that partial grant of ten satellites will facilitate continued development and testing of SpaceX’s broadband service in high latitude geographic areas in the immediate term pending later action to address arguments in the record as to both grant of the modification as a whole and the full subset of polar orbit satellites,” the order stated.

- It rejected Viasat’s opposition to the request, stating that allowing the 10 satellites “does not present concerns in connection with the issues raised by commenters.” That included orbital debris concerns about failed Starlink satellites. “We conclude that the addition of these ten satellites is unlikely to have any significant incremental effect on the operations of other satellites in the relevant orbital altitudes,” the order stated.

- The FCC, though, deferred a decision on SpaceX’s overall license modification request to lower the orbits of those satellites. In the order, the FCC didn’t state when it expected to rule on the full request.

• December 8, 2020: Observations conducted by the Murikabushi Telescope of Ishigakijima Astronomical Observatory in Japan confirmed that dark coating can reduce satellite reflectivity by half. There are concerns that numerous artificial satellites in orbit could impair astronomical observations, but these findings may help alleviate such conditions. 55) 56)

- Today's growing demand for space-based services has spawned a wave of satellite constellation projects which operate numerous artificial satellites in orbit. Since these satellites can shine by reflecting sunlight, the astronomy community has raised concerns about their potential impact on astronomical observations. In January 2020, SpaceX launched "DarkSat," an experimental satellite with an anti-reflective coating, and asked astronomers to assess how much this coating can reduce the satellite reflectivity. Brightness measurements of artificial satellites have already been conducted, but until now, there was no verification that a dark coating actually achieves the expected reflectivity reduction.

- The Murikabushi Telescope of Ishigakijima Astronomical Observatory can observe celestial objects simultaneously in three different wavelengths (colors). Comparing multicolor data obtained under the same conditions provides more accurate insight into how much the coating can reduce the satellite brightness. Observations conducted from April to June 2020 revealed for the first time in the world that artificial satellites, whether coated or not, are more visible at longer wavelengths, and that the black coating can halve the level of surface reflectivity of satellites. Such surface treatment is expected to reduce the negative impacts on astronomical observations. Further measures will continue to be implemented to pave the way for peaceful coexistence between space industries and astronomy.

• December 7, 2020: The Federal Communications Commission (FCC) on Monday awarded SpaceX's Starlink Internet venture $885 million in a broadband services auction for rural America. It was the fourth-largest award in recent competitive bidding. 57)

- The win provides new funding to Starlink, which recently provided free public testing in limited areas of the northwestern United States and Canada. The money also will help Starlink move toward bringing better-quality and faster Internet service to rural areas.

- Elon Musk's company has more than 900 Starlink communications satellites in orbit and intends to launch hundreds more.

- SpaceX won bids to provide broadband in 35 states, more states than any of the 180 companies that bid in the recent auction, which covered 49 states.

- The contracts are a significant win for SpaceX, said Shagun Sachdeva, who has worked as an analyst covering large satellite constellations and recently founded her own consulting company, France-based Kosmic Apple.

- "If SpaceX manages to get government and military contracts for Starlink, as they seem to be successfully doing so far, they can keep the commercial costs low enough to gain a decent market share," Sachdeva said.

- The FCC funding and recent public testing mean SpaceX is "most definitely one of the front runners now" in providing broadband service, she said.

- The companies that won more funding than SpaceX were LTD Broadband, which operates in the Upper Midwest, at $1.32 billion; Connecticut-based Charter Communications, $1.22 billion; and Rural Electric Cooperation Consortium, a nationwide collection of rural utilities, at $1.1 billion.

- SpaceX Starlink satellites operate at LEO (Low Earth Orbit) altitudes of roughly 550 km according to SpaceX.

- Winning bids in the auction allows SpaceX to submit formal applications for contract Internet service in rural areas. SpaceX has advertised Starlink at $99 a month after the purchase of a satellite dish receiver for $499, but the FCC funding is to be used partly to lower those costs for rural areas.

August 26, 2020: Light pollution problem from large satellite constellations for astronomy
A new report offers ways both astronomers and satellite developers can reduce the effect megaconstellations have on ground-based astronomy, but warned that no combination of measures can entirely eliminate the problem. 58)

- The report released Aug. 25 by the AAS (American Astronomical Society) and the National Science Foundation’s NOIRLab (National Optical-Infrared Astronomy Research Laboratory) is the outcome of a four-day workshop called ”Satellite Constellations 1 Workshop Report” (SATCON1) held nearly two months ago. That workshop brought together more than 250 people, including both astronomers and satellite operators, to evaluate how to minimize the effect satellite constellations would have on astronomy.

- For more than a year, astronomers have expressed concern that constellations of thousands of satellites could interfere with their observations. The satellites, visible through reflected sunlight, can leave bright streaks as they pass through the fields of view of telescopes.

- The workshop concluded that while there are a number of ways to reduce the problem, there is no panacea. “No combination of mitigations will eliminate the impact of satellite constellations on optical astronomy,” said Connie Walker of NOIRLab, one of the co-chairs of the workshop, in an Aug. 25 press conference. The exception, she said, was not to launch such systems at all, but acknowledged “it’s not viable for industry.”

- Instead, the report offered a set of recommendations to mitigate the effects of megaconstellations on astronomy, including ways for companies to reduce the brightness of their satellites and the amount of time they are visible in the night sky. Those steps include placing satellites in orbits no higher than 600 kilometers, as well as darkening them and controlling their attitude to reduce their reflectivity.

- Even before the SATCON1 workshop, astronomers had been working with SpaceX on mitigation measures along the lines of those steps described in the report. The Starlink satellites operate at an altitude of 550 kilometers, and the company has tested measures to both darken the satellites to reduce their reflectivity as well as to install visors to block sunlight from hitting reflective surfaces.

- The first “VisorSat” satellite launched in June and, earlier this month, reached its operational orbit. Astronomers said it was still too soon to measure its effectiveness. “We don’t have a complete set of observations yet,” said Lori Allen of NOIRLab, who chaired a SATCON1 working group on observations. “We do have some initial observations, but those are still under analysis.”

- Allen said that the effort to measure the brightness of VisorSat had been affected by observatories that remain closed because of the pandemic. However, some amateur satellite observers have observed the first VisorSat this month and estimate its brightness at seventh magnitude, enough of a reduction to reduce the worst impacts on astronomy.

- The efforts to reduce the brightness of Starlink satellites are much further along than those of other satellite constellations, such as OneWeb and Amazon’s Project Kuiper. OneWeb, which paused the deployment of its constellation after filing for Chapter 11 bankruptcy in March, worries astronomers because its satellites are in orbits 1,200 kilometers high, making them visible longer each night. The company also recently filed a proposal to operate as many as 48,000 additional satellites.

- “SpaceX is leading the charge in terms of trying to understand these issues and designing mitigations on their satellites,” said Tony Tyson, chief scientist of the Vera Rubin Observatory and chair of a SATCON1 working group devoted to mitigation measures.

- “Others are getting interested,” he added, notably OneWeb and Amazon, which participated in the workshop, “but we’re nowhere near any kind of down-to-earth engineering discussions on how to do this.”

- The report included recommendations for astronomers as well, such as development of software to plan observations to avoid or minimize the number of satellites passing through the field of view, as well as software to identify and remove trails created by passing satellites. It also recommended astronomers and satellite operators work together to coordinate observations of satellites to measure changes in brightness over time, and to share more accurate satellite position data to enable astronomers to more effectively avoid satellites.

- “We need to greatly increase the precision of publicly available positions” of satellites, said Jeff Hall of Lowell Observatory, the other co-chair of the SATCON1 workshop. “They’re not accurate enough for observatories to work around some of the issues that we’re facing.”

- The report did not examine regulatory or policy issues involving satellite megaconstellations and astronomy. That will be the subject of a second workshop tentatively scheduled for the first half of 2021.

- The SATCON1 workshop is not the only study of the topic. The NSF commissioned a report from the independent JASON scientific advisory group on the effects megaconstellations have on astronomy in general. Ralph Gaume, director of the NSF’s astronomical sciences division, said at an Aug. 25 meeting of the Astro2020 decadal survey steering committee that he received an initial “letter report” from the group a week ago, and expected the final report around October 1.

- Phil Puxley, vice president for special projects at the Association of Universities for Research in Astronomy, which operates NOIRLab for the NSF, noted at the SATCON1 briefing that astronomers previously built observatories in remote locations to avoid terrestrial light pollution. But with constellations, he said, “there are no remote locations that are immune. There is no place to hide.”

• August 25, 2020: Satellite Constellations 1 Workshop Report (SATCON1). The content of Table 1 contains only the Executive Summary of the SATCON1 paper. 59)

Existing and planned large constellations of bright satellites in low-Earth orbit (LEOsats) will fundamentally change astronomical observing at optical and near-infrared (NIR) wavelengths. Nighttime images without the passage of a Sun-illuminated satellite will no longer be the norm. If the 100,000 or more LEOsats proposed by many companies and many governments are deployed, no combination of mitigations can fully avoid the impacts of the satellite trails on the science programs of current and planned ground-based optical-NIR astronomy facilities. Astronomers are just beginning to understand the full range of impacts on the discipline. Astrophotography, amateur astronomy, and the human experience of the stars and the Milky Way are already affected. This report is the outcome of the Satellite Constellations 1 (SATCON1) workshop held virtually on 29 June–2 July 2020. SATCON1, organized jointly by NSF’s NOIRLab and AAS with funding from NSF, aimed to quantify better the impacts of LEOsat constellations at optical wavelengths and explore possible mitigations.

Recent technology developments for astronomical research — especially wide-field imaging on large optical telescopes — face significant challenges from the new ability in space and communication technologies to launch many thousands of LEOsats rapidly and economically. This troubling development went unnoticed by our community as recently as 2010, when New Worlds, New Horizons — the most recent National Academies’ decadal survey of astronomy and astrophysics — was issued. In the last year, the sky has changed, with growing numbers of satellite trails contaminating astronomical images.

Many astronomical investigations collect data with the requirement of observing any part of the sky needed to achieve the research objective with uniform quality over the field of view. These include studies that are among the highest priorities in the discipline: stellar populations in the Milky Way and neighboring galaxies; searches for potentially hazardous near-Earth objects; identification of gravitational wave sources such as neutron star mergers; and wide-area searches for transiting exoplanets. At a minimum, a fraction of the area being imaged is lost to the trails or significantly reduced in S/N (signal-to-noise ratio). However, many of these areas of research also include a time-critical aspect and/or a rare, scientifically critical target. Such a missed target, even with low probability, will significantly diminish the scientific impact of the project. For example, if a near-Earth object is not recovered, its orbital parameters are lost. If the transit of a promising super-Earth exoplanet candidate is missed, the orbital timing may not be recovered. If the optical counterpart of a gravitational wave source is lost in the few percent of pixels in satellite trails, its rapid fading may preclude subsequent identification. Detailed simulations beyond the scope of this workshop are required to better quantify the potential scientific cost of losing uniform full area coverage in these cases.

Even more challenging simulations are required to understand the impact on very large samples (e.g., from Vera C. Rubin Observatory) that are limited not by small number statistics but rather by systematic uncertainties. One measure of precision cosmology, for example, is the gravitational weak lensing shear that elongates faint galaxy images, and more complex modeling is needed to understand the major impact these satellites will have on this field.

Initial visibility simulations have shown the significant negative impacts expected from two communications-focused LEOsat constellations, Starlink (launched by Space Exploration holdings, LLC [SpaceX]), and OneWeb. For SATCON1, simulations were performed of the visibility of LEOsats with 30,000 second-generation Starlink satellites below 614 km and ~48,000 OneWeb satellites at 1200 km, in accord with the FCC filings for these projects. For all orbital heights, the visibility of sunlit satellites remains roughly constant between sunset and astronomical twilight (Sun 18 degrees below the horizon). The key difference between lower (~600 km) and higher (~1200 km) orbits is the visibility in the dark of night between astronomical twilights: higher altitude constellations can be visible all night long during summer, with only a small reduction in the number visible compared to those in the twilight.

Mitigation of the most damaging impacts on scientific programs is now being actively explored by the professional astronomy community worldwide. These investigations have benefited from collaboration with SpaceX, the first operator to launch a substantial constellation of LEOsats (538 satellites over 9 launches as of July 2020). Changes are required at both ends: constellation operators and observatories. SpaceX has shown that operators can reduce reflected sunlight through satellite body orientation, Sun shielding, and surface darkening. A joint effort to obtain higher accuracy public data on predicted locations of individual satellites (or ephemerides) could enable some pointing avoidance and mid-exposure shuttering during satellite passage. Observatories will need to adopt more dynamic scheduling and observation management as the number of constellation satellites increases, though even these measures will be ineffective for many science programs.

SATCON1 was attended by over 250 astronomers and engineers from commercial operators (mainly from SpaceX since they are furthest along in their work on this issue), as well as other stakeholders, and reached a number of conclusions and recommendations for future work. The organizers hope that the collegiality and spirit of partnership between these two communities will expand to include other operators and observatories and continue to prove useful and productive. Our findings and recommendations should serve as guidelines for observatories and satellite operators alike to use going forward, even as we work toward a more detailed understanding of the impacts and mitigations.

Table 1: Impact of Satellite Constellations on Optical Astronomy and Recommendations toward Mitigations

• May 15, 2020: Every two weeks, late in the evening, people are able to see a swarm of strikingly bright points of light crossing the night sky. An array of images and spectacular videos of such sightings circulate on social media. Word soon gets around that these glowing strings of light are not, in fact, an alien fleet. Rather, they are the Starlink satellites from SpaceX, the US space company run by Elon Musk, streaking across the night sky in 'trains'. 60)

- This visual spectacle and the ambitious project behind it, which is on an enormous scale, are fascinating. Felix Huber and Manfred Gaida explain the background to the project in an interview. They talk about the impact that these strings of light have on astronomy and space, and answer the questions that people sent to DLR when it put out a call on social media.

- Felix Huber is Director of DLR Space Operations and Astronaut Training. This is the central institution for spaceflight operations in Germany. Manfred Gaida is an astronomer and researcher at the DLR Space Administration and an expert on satellite-based space research and optical astronomy.

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Figure 24: Eye-catching newcomers to the sky (image credit: Giancarlo Foto4U CC-BY 2.0)

• April 27, 2020: SpaceX Chief Executive Elon Musk said April 27 that he hopes to test a new way to reduce the brightness of the company’s Starlink satellites on the next launch for the broadband megaconstellation. 61)

- In a briefing to a committee working on the next astrophysics decadal survey, Musk said the experimental “VisorSat,” along with a new approach for orienting Starlink satellites as they raise their orbits, should address concerns raised by astronomers that the Starlink constellation could interfere with their observations.

- “Our objectives, generally, are to make the satellites invisible to the naked eye within a week, and to minimize the impact on astronomy, especially so that we do not saturate observatory detectors and inhibit discoveries,” Musk said.

- SpaceX first attempted to address the brightness problem with an experimental “DarkSat” included in a batch of Starlink satellites launched in January. The satellite used what the company described as experimental darkening treatments over reflective surfaces, like its antennas, in an effort to reduce the amount of sunlight it reflects and thus make it darker.

- While DarkSat has shown some promise, appearing about one magnitude darker than untreated Starlink satellites, the company is moving in a different direction. “We found an option that is even better than that, which is basically to give the satellites shades,” he said.

- Musk and others at SpaceX have previously discussed a sunshade that they compared to a patio umbrella that would deploy from a satellite, keeping the antennas in shadow. Musk, at the committee meeting, described a concept called VisorSat that would deploy panels, like sun visors mounted on a car windshield, to block the sun.

- “We have a radio-transparent foam that will deploy nearly upon the satellite being released, and it blocks the sun from reaching the antennas,” he said. “They’re sun visors, essentially: they flip out and block the sun and prevent reflections.” He predicted that the visors would have a “massive effect” on the brightness of the satellites.

- SpaceX is planning test VisorSat on the company’s next Starlink launch. “It’s a bit of a challenge, but that’s our goal,” he said. He didn’t say how many satellites would be equipped with visors, or when the launch was scheduled. SpaceX has been performing Starlink launches at the rate of at least one a month so far this year, most recently April 22.

- A second effort involves the brightness of the satellites as they raise their orbits after launch. Musk said the satellites appear bright because of the orientation of the solar panels, which are aligned differently during orbit raising than once at their operational orbit.

- As soon as this week, Musk said SpaceX will try an “orientation roll” to change the alignment of the solar panels relative to the Earth, reducing the amount of sunlight they reflect to the ground. “Early indications are this will have a significant effect on the brightness during orbit raise,” he said. “The satellites will be significantly less visible from the ground.”

- The measures SpaceX has taken have come after months of discussions with astronomers, who have been worried about the effects a full constellation of Starlink satellites — about 12,000 according to current plans, with proposals for up to 30,000 more — would have on astronomy. The situation was of particular concern to those operating telescopes with wide fields of view, like the Vera Rubin Observatory under construction in Chile, where Starlink satellites would be visible in a large fraction of images taken each night.

- In a separate presentation to the committee earlier in the day, Tony Tyson, chief scientist for the Rubin Observatory, said the concern was that the brightness of unmodified Starlink satellites would cause “nonlinear crosstalk,” or severe image artifacts, in the observatory’s camera. “We would be left with all of these fake trails, fake galaxies, etc., in our data, damaging the science,” he said.

- SpaceX has already made progress darkening the satellites, with newer satellites about one magnitude darker than the original “v0.9” satellites launched in May 2019 even without the darkening treatments used on DarkSat. If the satellites can be made about a factor of two darker than DarkSat, Tyson said a technique to correct for the nonlinear crosstalk can work, although it is computer intensive and won’t correct for the original streak left in the images by passing satellites.

- The new approaches won’t address the issue of brightness of existing Starlink satellites, but Musk said their lifetime is limited. He estimated the initial generation of satellites will be deorbited in about three to four years to make way for improved satellites. “We’ll just have far greater throughput capability with version two” of the Starlink satellites, he said.

- While the focus of the committee presentation and subsequent discussion, which lasted for more than an hour, was on Starlink, there was some talk about the role SpaceX could play in supporting space-based astronomy, which is not affected by Starlink or other megaconstellations.

- “I’m very excited about the future of space-based telescopes that could be very large,” he said. He mentioned Starship, the company’s next-generation large reusable launch system, which will begin regular flights “I think within a couple of years,” he promised. “It allows for space telescopes to be transported to orbit at probably an order of magnitude lower cost than in the past.”

- “I’m pretty interested in trying to figure out how to help launch and possibly build a big observatory in space,” he said, offering to meet with astronomers to discuss mission concepts. “Like a planet imager or something like that.”

• March 19, 2020: SpaceX, the largest commercial satellite constellation operator in the world, has ambitious plans of installing 12,000 satellites in low-orbit over a span of several years, as part of its Starlink project to provide low-cost broadband internet service. 62)

A well-known astronomer and satellite tracker has voiced concerns that efforts to scan the skies for potentially dangerous near-Earth asteroids might be in jeopardy due to ambitious plans by SpaceX to deploy over 12,000 satellites in low-Earth orbit over the next several years.

The study "The Low Earth Orbit Satellite Population and Impacts of the SpaceX Starlink" by Jonathan McDowell from the Harvard-Smithsonian Center for Astrophysics analyses the impact that the broadband service mega-constellation could have on different observatories. 63)

The research, still awaiting peer review and accepted for pre-print publication in Astrophysical Journal Letters, states:

"Astronomers - and casual viewers of the night sky - must expect a future in which the low Earth orbit population includes tens of thousands of relatively large satellites."

The researcher has modelled how many satellites in a constellation of 12,000 that the FCC has already approved for SpaceX would be lit up by the Sun and above the horizon from three different latitudes on Earth.

"We see that several hundred satellites are above the horizon at all times of night; during winter twilight, and all summer night long, most of them are illuminated," writes McDowell.

Since Elon Musk's SpaceX began launching batches of satellites in 2019, astronomers have been voicing concerns that the expanding number of huge satellite constellations, driven by Starlink's target plan of installing up to 42,000 satellites in low orbit could wreak havoc on scientific observations of space.

Both skywatchers and astronomers were shocked by the bright lights of the satellites that were obstructing the view for major telescopes and potentially corrupting between 30 to 40 percent of astronomical images.

Satellites from companies other than SpaceX, such as OneWeb pose a similar problem, as many observatories with particularly wide fields of view, like the Vera C. Rubin Observatory currently under construction in Chile, are likely to be impacted.

According to a recent study from the European Southern Observatory (ESO), satellite mega-constellations are projected as "severely" affecting between 30 and 50 percent of observations taken by the Rubin Observatory.

"However, there appear to be other science projects which may be more severely affected... For example, searches for near-Earth asteroids include observations taken in twilight, a time when the satellites are illuminated year-round," writes McDowell.

The astronomer has recently been expounding the importance of continued, unhampered observation of asteroids that may pose a danger to the Earth due to the close proximity in which they move.

When it comes to detection of near-Earth objects travelling close to the Sun, researchers typically search for them after sunset, when Starlink's satellites illuminate the sky.

While urging additional regulation, which he claimed might help solve the issue, he stressed measures being proposed at the moment are not effective.

There has been no official comment from SpaceX.

Previously, to allay concerns, SpaceX CEO Elon Musk stated the company would work with astronomers to develop solutions to mitigate any impact on scientific observation. In response to the criticism, Elon Musk tweeted in May 2019 that the amount of light the satellites have been sending down toward Earth would be studied and measures to mitigate the effects would be taken by modifying them to be less reflective.

"Agreed, sent a note to Starlink team last week specifically regarding albedo reduction. We'll get a better sense of value of this when satellites have raised orbits and arrays are tracking to Sun."

Meanwhile, the company continues to launch new batches of satellites, as a Falcon 9 rocket is geared up to carry 60 more satellites to space on 18 March.

SpaceX has plans to have over 1,500 satellites in space by the end of the year, with the long-term plan for the mega-constellation aiming at 42,000 satellites that would beam high-speed internet to every corner of the globe.

• March 5, 2020: Astronomers have recently raised concerns about the impact of satellite mega-constellations on scientific research. To better understand the effect these constellations could have on astronomical observations, ESO commissioned a scientific study of their impact, focusing on observations with ESO telescopes in the visible and infrared but also considering other observatories. The study, which considers a total of 18 representative satellite constellations under development by SpaceX, Amazon, OneWeb and others, together amounting to over 26 thousand satellites [1], has now been accepted for publication in Astronomy & Astrophysics. 64) 65)
Note [1]: Many of the parameters characterizing satellite constellations, including the total number of satellites, are changing on a frequent basis. The study assumes 26,000 constellation satellites in total will be orbiting the Earth, but this number could be higher.

The study finds that large telescopes like ESO's Very Large Telescope (VLT) and ESO's upcoming Extremely Large Telescope (ELT) will be "moderately affected" by the constellations under development. The effect is more pronounced for long exposures (of about 1000 s), up to 3% of which could be ruined during twilight, the time between dawn and sunrise and between sunset and dusk. Shorter exposures would be less impacted, with fewer than 0.5% of observations of this type affected. Observations conducted at other times during the night would also be less affected, as the satellites would be in the shadow of the Earth and therefore not illuminated. Depending on the science case, the impacts could be lessened by making changes to the operating schedules of ESO telescopes, though these changes come at a cost [2]. On the industry side, an effective step to mitigate impacts would be to darken the satellites.
Note [2]: Examples of mitigation measures include: computing the position of the satellites to avoid observing where one will pass; closing the telescope shutter at the precise moment when a satellite crosses the field of view; and constraining observations to areas of the sky that are in Earth’s shadow, where satellites are not illuminated by the sun. These methods, however, are not suitable for all science cases.

The study also finds that the greatest impact could be on wide-field surveys, in particular those done with large telescopes. For example, up to 30% to 50% of exposures with the US National Science Foundation's Vera C. Rubin Observatory (not an ESO facility) would be "severely affected”, depending on the time of year, the time of night, and the simplifying assumptions of the study. Mitigation techniques that could be applied on ESO telescopes would not work for this observatory although other strategies are being actively explored. Further studies are required to fully understand the scientific implications of this loss of observational data and complexities in their analysis. Wide-field survey telescopes like the Rubin Observatory can scan large parts of the sky quickly, making them crucial to spot short-lived phenomena like supernovae or potentially dangerous asteroids. Because of their unique capability to generate very large data sets and to find observation targets for many other observatories, astronomy communities and funding agencies in Europe and elsewhere have ranked wide-field survey telescopes as a top priority for future developments in astronomy.

Professional and amateur astronomers alike have also raised concerns about how satellite mega-constellations could impact the pristine views of the night sky. The study shows that about 1600 satellites from the constellations will be above the horizon of an observatory at mid-latitude, most of which will be low in the sky — within 30 degrees of the horizon. Above this — the part of the sky where most astronomical observations take place — there will be about 250 constellation satellites at any given time. While they are all illuminated by the Sun at sunset and sunrise, more and more get into the shadow of the Earth toward the middle of the night. The ESO study assumes a brightness for all of these satellites. With this assumption, up to about 100 satellites could be bright enough to be visible with the naked eye during twilight hours, about 10 of which would be higher than 30 degrees of elevation. All these numbers plummet as the night gets darker and the satellites fall into the shadow of the Earth. Overall, these new satellite constellations would about double the number of satellites visible in the night sky to the naked eye above 30 degrees [3].
Note [3]: It is estimated that about 34,000 objects greater than 10 cm in size are currently orbiting the Earth. Of these, about 5500 are satellites, including about 2300 functional ones. The remainder are space debris, including rocket upper stages and satellite launch adapters. About 2000 of these objects are above the horizon at any given place at any one time. During twilight hours, about 5–10 of them are illuminated by the Sun and bright enough to be seen with the naked eye.

These numbers do not include the trains of satellites visible immediately after launch. Whilst spectacular and bright, they are short lived and visible only briefly after sunset or before sunrise, and — at any given time — only from a very limited area on Earth.

The ESO study uses simplifications and assumptions to obtain conservative estimates of the effects, which may be smaller in reality than calculated in the paper. More sophisticated modelling will be necessary to more precisely quantify the actual impacts. While the focus is on ESO telescopes, the results apply to similar non-ESO telescopes that also operate in the visible and infrared, with similar instrumentation and science cases.

Satellite constellations will also have an impact on radio, millimeter and submillimeter observatories, including the Atacama Large Millimeter/submillimeter Array (ALMA) and the Atacama Pathfinder Experiment (APEX). This impact will be considered in further studies.

ESO, together with other observatories, the International Astronomical Union (IAU), the American Astronomical Society (AAS), the UK Royal Astronomical Society (RAS), and other societies, is taking measures to raise the awareness of this issue in global fora such as the United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) and the European Committee on Radio Astronomy Frequencies (CRAF). This is being done while exploring with the space companies practical solutions that can safeguard the large-scale investments made in cutting-edge ground-based astronomy facilities. ESO supports the development of regulatory frameworks that will ultimately ensure the harmonious coexistence of highly promising technological advancements in low Earth orbit with the conditions that enable humankind to continue its observation and understanding of the Universe.

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Figure 25: This annotated image shows the night sky at ESO's Paranal Observatory around twilight, about 90 minutes before sunrise. The blue lines mark degrees of elevation above the horizon. A new ESO study looking into the impact of satellite constellations on astronomical observations shows that up to about 100 satellites could be bright enough to be visible with the naked eye during twilight hours (magnitude 5–6 or brighter). The vast majority of these, their locations marked with small green circles in the image, would be low in the sky, below about 30 degrees elevation, and/or would be rather faint. Only a few satellites, their locations marked in red, would be above 30 degrees of the horizon — the part of the sky where most astronomical observations take place — and be relatively bright (magnitude of about 3–4). For comparison, Polaris, the North Star, has a magnitude of 2, which is 2.5 times brighter than an object of magnitude 3. The number of visible satellites plummets towards the middle of the night when more satellites fall into the shadow of the Earth, represented by the dark area on the left of the image. Satellites within the Earth's shadow are invisible. (image credit: ESO/Y. Beletsky/L. Calçada)

• June 14, 2019: SpaceX’s ambitious Starlink project could eventually launch more than 10,000 satellites into orbit and rewrite the future of the internet. But Elon Musk’s company SpaceX has been taking heat from the astronomical community after an initial launch in late May released the first 60 satellites. The satellites with a mass of 227 kg were clearly visible in Earth’s night sky, inspiring concern that they could increase light pollution, interfere with radio signals, and contribute to the growing issue of space debris. 66)

This week, the American Astronomical Society, the International Astronomical Union, the British Royal Astronomical Society, and the International Dark-Sky Association (IDA) all issued statements expressing concern about Starlink’s potential to damage astronomical research by leaving bright streaks through images.

“The Starlink affair has raised the attention of the astronomy community in a way that I’ve not seen during my couple of decades in it,” says John Barentine, director of public policy at the IDA, which lobbies against light pollution. “I hope that this moment is the wake-up call that is needed to prompt a new discussion in the international community about the nature of outer space, especially near the Earth, in a commercial context.”

Musk had repeatedly assured people on Twitter that his satellites wouldn’t be visible at night, so the light caught some people by surprise. However, the satellites’ initial brightness is intended to wane as they climb higher into their permanent orbits.

“The observability of the Starlink satellites is dramatically reduced as they raise orbit to greater distance and orient themselves with the phased array antennas toward Earth and their solar arrays behind the body of the satellite,” a spokesperson for SpaceX said in an email.

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Figure 26: Telescopes at Lowell Observatory in Arizona captured this image of galaxies on May 25, their images marred by the reflected light from more than 25 Starlink satellites as they passed overhead (image credit: Victoria Girgis/Lowell Observatory)

But Barentine and other astronomers aren’t so sure, especially given that this is only the beginning for Starlink. Plus, many other companies — including Amazon, Boeing, OneWeb, Telesat, LeoSat, and even Facebook — are planning other so-called “mega-constellations” for connecting the masses online.

“There are billions of people around the world who lack access to broadband internet,” a spokesperson for Amazon’s Project Kuiper said in an email. “Our vision is to provide low-latency, high-speed broadband connectivity to many of these unserved and underserved communities around the world .... Many of our satellite and mission design decisions are, and will continue to be, driven by our goals of ensuring space safety and taking into account concerns about light pollution.”

But there are already 22,000 artificial objects currently in orbit. And as the microlaunch space race kicks into high gear, that number is destined to double. Communications satellites aren’t the only things headed up, either. One group even proposed launching orbiting billboards that would shine ads back down to Earth. And an artist recently launched the “Humanity Star” – a purely artistic light beacon.

“Space is already crowded, and roughly doubling the number of objects in low- and near-Earth orbit will only add to the visual pollution of the night sky,” Barentine says. “Being in a dark place and seeing one satellite fly over every few minutes is one thing. But seeing literally dozens of them at any given time for hours every night is another story entirely.”

Part of the reason this problem stands to get worse, according to astrophysicist Laura Forczyk, is “there is no regulatory body in the United States that directs companies as to the kind of light pollution or the brightness of satellites. This is a fairly new topic and as always the government regulations are behind technology.”

But Forczyk, owner of the space consulting firm Astralytical, also says that changing the night skies isn’t the same thing as losing the night sky — and it’s a little too early to know what the total impact is going to be. After all, the Starlink satellites still haven’t reached their final orbit. “We’re very reactive when it comes to these kinds of things,” she says, but emphasizes miscommunication from both sides.

Whether the problem stands to worsen or not, most experts see the growth of these mega-constellations as inevitable.

“I don’t think we’re going to be able to create political will to stop the satellites because there is so much commercial potential and politicians tend to respond to economics,” says Phil Metzger, a planetary scientist at the University of Central Florida and a former NASA physicist. However, he says future designs of satellites can ensure they’ll cause less interference with on-the-ground astronomy.

“We can change the surface of the spacecraft so it is more absorptive and less reflective or we can even make it more transparent,” Metzger says. “We do have the ability to make electrical conductors completely transparent so we don’t need metal. You could have glass with transparent conductors in the glass ... I think we’ll probably be doing all of these things in the future.”


• January 9, 2020: The aerospace company SpaceX launched 60 of its Starlink broadband Internet satellites into orbit on 6 January 2020 — including one, called DarkSat, that is partially painted black. The probe is testing one strategy to reduce the brightness of satellite ‘megaconstellations’, which scientists fear could interfere with astronomical observations. 67)

Various companies plan to launch thousands of Internet satellites in the coming years; SpaceX, of Hawthorne, California, aims to launch 24 batches of Starlinks this year. By the mid-2020s, thousands to tens of thousands of new satellites could be soaring overhead. Bright streaks caused by light reflecting off them could degrade astronomical images.

“I was complaining to my wife that I can’t sleep very well these days because of this,” says Tony Tyson, a physicist at the University of California, Davis, and chief scientist of the Vera C. Rubin Observatory, a major US telescope under construction in Chile. (It was renamed this week from the Large Synoptic Survey Telescope to honor the late Rubin, who discovered evidence for the existence of dark matter.)

Astronomers discussed the potential impacts of the satellites on various telescopes, and what could be done about them, on 8 January at a meeting of the American Astronomical Society in Honolulu, Hawaii. “2020 is the window to figure out what makes a difference in reducing the impact,” says Jeffrey Hall, director of Lowell Observatory in Flagstaff, Arizona, and chair of the society’s committee on light pollution.

“SpaceX is absolutely committed to finding a way forward so our Starlink project doesn’t impede the value of the research you all are undertaking,” Patricia Cooper, SpaceX’s vice-president for satellite government affairs, told a session at the astronomy meeting.

Star light, star bright: Three batches of Starlinks have been launched, for a total of about 180 satellites so far. They are most obvious in the night sky immediately after launch, before they boost their orbits to higher altitudes where they are farther away and appear dimmer. It’s not yet clear how significant a problem Starlinks will be for astronomy; scientists have complained about trails in their images since the first launch, but if the company ultimately moves to paint most of the Starlinks black, the impact could be substantially reduced.

Many astronomers panicked in June, soon after SpaceX launched the first batch of 60 Starlinks and telescopes began photographing their trails. Their brightness came as a surprise, says Patrick Seitzer, an astronomer at the University of Michigan in Ann Arbor. “The new megaconstellations coming online have the potential to be brighter than 99% of everything else in Earth orbit, and that’s where the concern comes from,” he says.

Several factors contribute to their puzzling brightness, astronomers reported at the meeting. SpaceX says the position of the solar panels might have something to do with it: at lower elevations, before the orbit boost, the satellites’ panels are positioned like an open book to reduce drag. That temporary orientation could make them reflect more sunlight. The speed at which a satellite moves across a telescope’s field of view is also important — the slower it moves, the more brightness accumulates per pixel of imagery.

There are no regulations that control how bright or dim a satellite needs to be, notes Ralph Gaume, director of the astronomical-sciences division of the US National Science Foundation in Alexandria, Virginia.

Twilight zone: Calculations suggest the Starlink trails will interfere with astronomy most significantly during the hours surrounding twilight and dawn. That’s a particular problem for observations that need to be made during twilight, such as searches for some near-Earth asteroids. And on short summer nights, the satellite trails could be visible all night long.

The Rubin Observatory is particularly vulnerable because it will scan huge amounts of the sky very frequently. When it begins operating in 2022, it will photograph the entire night sky every three days, for ten years.

Tyson’s team is working on possible software fixes for the anticipated satellite trails, such as ways to electronically erase trails and other glitches they induce in astronomical images. But “we’re still left with all the complexity of having all these things removed and all these systematic errors”, Tyson says.

If telescope operators know precisely where each satellite will appear and at what time, they can swivel the telescope to point at a different part of the sky that does not have a satellite in it, says Tyson. That’s feasible if there are 1,000 satellites, but not if there are tens of thousands, because the telescope loses so much time maneuvering that “it’s hopeless”, he says.

That leaves darkening as a leading option. With DarkSat, SpaceX engineers painted surfaces on the satellite that scatter light or reflect light diffusely, says Cooper. That could make them faint enough to be invisible to anyone looking up at a typical night sky — but almost certainly still visible to most astronomical research telescopes.

“It’s still going to be very much a part of astronomers’ lives,” says Jonathan McDowell, an astronomer at the Harvard–Smithsonian Center for Astrophysics in Cambridge, Massachusetts. “Just not a part of everyone’s lives.”



1) Matt Williams, ”SpaceX’s Starlink Constellation Construction Begins. 2,200 Satellites Will go up Over the Next 5 years,” Universe Today, 16 April 2019, URL: https://www.universetoday.com/141980/
spacexs-starlink-constellation-construction-begins-2200-satellites-will-go-up-over-the-next-5-years/

2) https://en.wikipedia.org/wiki/Starlink_(satellite_constellation)

3) Elon Musk, ”Starlink,” August 20, 2019, https://www.starlink.com/

4) Jeff Foust, ”SpaceX adds to latest funding round,” SpaceNews, 15 April 2021, URL: https://spacenews.com/spacex-adds-to-latest-funding-round/

5) J. D. Harrington, ”NASA, SpaceX Sign Joint Spaceflight Safety Agreement,” NASA Commercial Space, Press Release 21-011, 18 March 2021, URL: https://www.nasa.gov
/press-release/nasa-spacex-sign-joint-spaceflight-safety-agreement

6) ”SpaceX launches public beta test of Starlink Internet service,” Space Daily, 27 October 2020, URL: https://www.spacedaily.com/reports/
SpaceX_launches_public_beta_test_of_Starlink_Internet_service_999.html

7) ”SpaceX, Microsoft partner in global satellite Internet project,” Space Daily, 21 October 2020, URL: https://www.spacedaily.com/reports/
SpaceX_Microsoft_partner_in_global_satellite_Internet_project_999.html

8) ”FCC Authorizes SpaceX To Deploy A Million Antennas For Starlink Satellites,” Satnews Daily, 23 March 2020, URL: http://www.satnews.com/story.php?number=280640621

9) Stephen Clark, ”SpaceX’s brisk Starlink launch cadence to continue next week,” Spaceflight Now, 14 January 2020, URL: https://spaceflightnow.com/2020/01/14/
spacexs-brisk-starlink-launch-cadence-to-continue-next-week/

10) Jeff Foust, ”SpaceX, astronomers working to address brightness of Starlink satellites,” Space News, 8 January 2020, URL: https://spacenews.com/
spacex-astronomers-working-to-address-brightness-of-starlink-satellites/

11) ”SpaceX seeking many more satellites for space-based internet grid,” Space Daily, 16 October 2019, URL: http://www.spacedaily.com/reports/
SpaceX_seeking_many_more_satellites_for_space-based_internet_grid_999.html

12) Eric Ralph, ”SpaceX CEO Elon Musk reveals radical Starlink redesign for 60-satellite launch,” Tesla Rati, 11 May 2019, URL: https://www.teslarati.com/spacex-starlink-satellites-tease-revolutionary-design/

13) Stephen Clark, ”FCC approves SpaceX’s plan to operate Starlink satellites at lower altitude,” Spaceflight Now, 30 April 2019, URL: https://spaceflightnow.com/2019/04/30/
fcc-approves-spacexs-plan-to-operate-starlink-satellites-at-lower-altitude/

14) Eric Ralph, ”SpaceX’s first dedicated Starlink launch announced as mass production begins,” Tesla Rati, 8 April 2019, URL: https://www.teslarati.com/spacex-starlink-first-launch-date/

15) ”SpaceX gets nod to put 12,000 satellites in orbit,” Phys.org, 16 November 2018, URL: https://phys.org/news/2018-11-spacex-satellites-orbit.html

16) ”SpaceX Receives FCC's Stamp of Approval to Launch 4,425 Broadband Satellites,” Satnews Daily, 2 April 2018, URL: http://www.satnews.com/story.php?number=1759391214

17) Jon Brodkin, ”FCC approves SpaceX plan to launch 4,425 broadband satellites,” ars Technica, 30 March 2018, URL: https://arstechnica.com/information-technology/2018/03
/spacex-gets-fcc-approval-to-build-worldwide-satellite-broadband-network/

18) ”SpaceX launches Falcon 9 with PAZ, Starlink demo and new fairing,” NASA Spaceflight.com, 22 February 2018, URL: https://www.nasaspaceflight.com/
2018/02/spacex-falcon-9-paz-launch-starlink-demo-new-fairing/

19) Jeff Foust, ”SpaceX launches another set of Starlink satellites as it nears global coverage,” SpaceNews, 7 April 2021, URL: https://spacenews.com/
spacex-launches-another-set-of-starlink-satellites-as-it-nears-global-coverage/

20) Jeff Foust, ”SpaceX marks anniversary of first launch with Starlink mission,” SpaceNews, 24 March 2021, URL: https://spacenews.com/spacex-marks-anniversary-of-first-launch-with-starlink-mission/

21) Jeff Foust, ”SpaceX sets new booster reuse mark with Starlink launch,” SpaceNews, 14 March 2021, URL: https://spacenews.com/spacex-sets-new-booster-reuse-mark-with-starlink-launch/

22) Jeff Foust, ”SpaceX launches Starlink satellites and expands international service,” SpaceNews, 11 March 2021, URL: https://spacenews.com/spacex-launches-starlink-satellites-and-expands-international-service/

23) Stephen Clark, ”SpaceX sticks 75th Falcon rocket landing after launching 60 more Starlink satellites,” Spaceflight Now, 4 March 2021, URL: https://spaceflightnow.com/2021/03/04/
spacex-sticks-75th-falcon-rocket-landing-after-launching-60-more-starlink-satellites/

24) Jeff Foust, ”SpaceX launches Starlink satellites, but booster landing fails,” SpaceNews, 16 February 2021, URL: https://spacenews.com/spacex-launches-starlink-satellites-but-booster-landing-fails/

25) Jeff Foust, ”Falcon 9 launches Starlink satellites,” SpaceNews, 4 February 2021, URL: https://spacenews.com/falcon-9-launches-starlink-satellites/

26) Stephen Clark, ”SpaceX smashes record with launch of 143 small satellites,” Spaceflight Now, 24 January 2021, URL: https://spaceflightnow.com/2021/01/24/
spacex-launches-record-setting-rideshare-mission-with-143-small-satellites/

27) Jeff Foust, ”SpaceX surpasses 1,000-satellite mark in latest Starlink launch,” SpaceNews, 20 January 2021, URL: https://spacenews.com/spacex-surpasses-1000-satellite-mark-in-latest-starlink-launch/

28) Stephen Clark, ”SpaceX sets new rocket reuse records with successful Starlink launch,” Spaceflight Now, 20 January 2021, URL: https://spaceflightnow.com/2021/01/20/
spacex-sets-new-rocket-reuse-records-with-successful-starlink-launch/

29) Stephen Clark, ”SpaceX launches 60 more Starlink satellites on 100th Falcon 9 flight,” Spaceflight Now, 25 November 2020, URL: https://spaceflightnow.com/2020/11/25/
spacex-launches-60-more-starlink-satellites-on-100th-falcon-9-flight/

30) Stephen Clark, ”SpaceX adds another 60 satellites to Starlink network,” Spaceflight Now, 24 October 2020, URL: https://spaceflightnow.com/2020/10/24/spacex-adds-another-60-satellites-to-starlink-network/

31) Stephen Clark, ”SpaceX launches another batch of Starlink satellites,” Spaceflight Now, 18 October 2020, URL: https://spaceflightnow.com/2020/10/18/spacex-launches-another-batch-of-starlink-satellites/

32) Jeff Foust, ”Falcon 9 investigation ongoing as SpaceX continues Starlink launches,” SpaceNews, 18 October 2020, URL: https://spacenews.com/
falcon-9-investigation-ongoing-as-spacex-continues-starlink-launches/

33) Stephen Clark, ”SpaceX breaks cycle of scrubs with successful Falcon 9 launch,” Spaceflight Now, 6 October 2020, URL: https://spaceflightnow.com/2020/10/06/
spacex-breaks-cycle-of-scrubs-with-successful-falcon-9-launch/

34) Stephen Clark, ”SpaceX launches more Starlink satellites, beta testing well underway,” Spaceflight Now, 3 September 2020, URL: https://spaceflightnow.com/2020/09/03/
spacex-launches-more-starlink-satellites-beta-testing-well-underway/

35) Stephen Clark, ”SpaceX adds more satellites to ever-growing Starlink network,” Spaceflight Now, 18 August 2020, URL: https://spaceflightnow.com/2020/08/18/
spacex-adds-more-satellites-to-ever-growing-starlink-network/

36) Stephen Clark, ”SpaceX closes out busy week with launch of more Starlink satellites,” Spaceflight Now, 7 August 2020, URL: https://spaceflightnow.com/2020/08/07/
spacex-closes-out-busy-week-with-launch-of-more-starlink-satellites/

37) ”SpaceX launched 10th Starlink batch,” Space Daily, 07 August 2020, URL: https://www.spacedaily.com/reports/SpaceX_launched_10th_Starlink_batch_999.html

38) Caleb Herny, ”SpaceX launches 58 Starlink satellites, three Planet SkySats on Falcon 9,” SpaceNews, 13 June 2020, URL: https://spacenews.com/
spacex-launches-58-starlink-satellites-three-planet-skysats-on-falcon-9/

39) ”SpaceX sets new mark in rocket reuse 10 years after first Falcon 9 launch,” Spaceflight Now, 4 June 2020, URL: https://spaceflightnow.com/2020/06/04/
spacex-sets-new-mark-in-rocket-reuse-10-years-after-first-falcon-9-launch/

40) ”SpaceX launch boosts Starlink network to 480 satellites,” Space Daily, 4 June 2020, URL: https://www.spacedaily.com/reports/SpaceX_launch_boosts_Starlink_network_to_480_satellites_999.html

41) ”SpaceX Successfully Launches 60 Starlink Satellites but is Unsuccessful with Recovery of First Stage,” Satnews Daily, 18 March 2020, URL: http://www.satnews.com/story.php?number=61076689

42) Stephen Clark, ”Falcon 9 rocket overcomes engine failure to deploy Starlink satellites,” Spaceflight Now, 18 March 2020, URL: https://spaceflightnow.com/2020/03/18/
falcon-9-rocket-overcomes-engine-failure-to-deploy-starlink-satellites/

43) Stephen Clark, ”SpaceX delivers more Starlink satellites to orbit, booster misses drone ship landing,” Spaceflight Now, 17 February 2020, URL: https://spaceflightnow.com/2020/02/17/
spacex-delivers-more-starlink-satellites-to-orbit-booster-misses-drone-ship-landing/

44) Stephen Clark, ”SpaceX boosts 60 more Starlink satellites into orbit after weather delays,” Spaceflight Now, 29 January 2020, URL: https://spaceflightnow.com/2020/01/29/
spacex-boosts-60-more-starlink-satellites-into-orbit-after-weather-delays/

45) Stephen Clark, ”SpaceX launches more Starlink satellites, tests design change for astronomers,” Spaceflight Now, 7 January 2020, URL: https://spaceflightnow.com/2020/01/07/
spacex-launches-more-starlink-satellites-tests-design-change-for-astronomers/

46) Stephen Clark, ”Successful launch continues deployment of SpaceX’s Starlink network,” Spaceflight Now, 11 November 2019, URL: https://spaceflightnow.com/2019/11/11/
successful-launch-continues-deployment-of-spacexs-starlink-network/

47) Chris Gebhardt, ”Falcon 9 launches first Starlink mission – heaviest payload launch by SpaceX to date,” NASA Spaceflight.com, 23 May 2019, URL: https://www.nasaspaceflight.com
/2019/05/first-starlink-mission-heaviest-payload-launch-spacex/

48) ”Sixty Launched ... 11,940 Left to Go ... as SpaceX Successfully Sends Off Their First Batch of Starlink Satellites,” Satnews Daily, 24 May 2019, URL: http://www.satnews.com/story.php?number=179808724

49) ”SpaceX launches first satellites of its internet network,” Space Daily, 24 May 2019, URL: http://www.spacedaily.com/reports/SpaceX_launches_first_satellites_of_its_internet_network_999.html .

50) Jason Rainbow, ”SpaceX takes aim at satellite mobility operators with Starlink expansion,” SpaceNews, 8 March 2021, URL: https://spacenews.com/
spacex-takes-aim-at-satellite-mobility-operators-with-starlink-expansion/

51) ”French village says 'non' to Elon Musk's space-age internet,” Space Daily, 19 February 2021, URL: https://www.spacedaily.com/reports/
French_village_says_non_to_Elon_Musks_space-age_internet_999.html

52) Michael Sheetz, ”SpaceX says its Starlink satellite internet service now has over 10,000 users,” CNBC, 4 February 2021, URL: https://www.cnbc.com/2021/02/04/
spacex-starlink-satellite-internet-service-has-over-10000-users.html

53) ”Statement on Satellite Constellations,” Press Release, AG (Astronomische Gesellschaft), 18 January 2021, URL: https://idw-online.de/de/news761318

54) Jeff Foust, ”FCC grants permission for polar launch of Starlink satellites,” SpaceNews, 9 January 2021, URL: https://spacenews.com/fcc-grants-permission-for-polar-launch-of-starlink-satellites/

55) ”Dark coating can reduce satellite reflectivity,” Science Daily, 8 December 2020, URL: https://www.sciencedaily.com/releases/2020/12/201208090000.htm

56) Takashi Horiuchi, Hidekazu Hanayama, and Masatoshi Ohishi, ”Simultaneous Multicolor Observations of Starlink's Darksat by the Murikabushi Telescope with MITSuME,” The Astrophysical Journal, Volume 905, Number 1, Published: 7 December 2020, https://doi.org/10.3847/1538-4357/abc695

57) ”SpaceX wins $885 million for Starlink broadband service,” Space Daily, 7 December 2020, URL: https://www.spacedaily.com/reports/SpaceX_wins_885_million_for_Starlink_broadband_service_999.html

58) Jeff Foust, ”Report outlines measures to reduce impact of satellite constellations on astronomy,” SpaceNews, 26 August 2020, URL: https://spacenews.com/
report-outlines-measures-to-reduce-impact-of-satellite-constellations-on-astronomy/

59) C. Walker, J. Hall, L. Allen, P. Seitzer, A. Tyson, A. Bauer, K. Krafton, J. Lownthal, J. Parriott, P. Puxley, T. Abbott, G. Bakos, J. Barentine, C. Bassa, J. Blakeslee, A. Bradshaw, J. Cooke, D. Devost, D. Galadi, F. Haase, O. Hainaut, S. Heathcote, M. Jah, H. Krantz, D. Kucharski, J. McDowell, P. Mroz, A. Otarola, E. Pearce, M. Rawls, C. Saunders, R. Seaman, J. Siminski, A. Snyder, L. Storrie-Lombardi, J. Tregloan-Reed, R. Wainscoat, A. Williams, and P. Yoachim, ”Satellite Constellations 1 Workshop Report,” AAS, 25 August 2020, URL: https://aas.org/satellite-constellations-1-workshop-report

60) ”Strings of pearls in the night sky – the Starlink satellite project,” DLR, 15 May 2020, URL: https://www.dlr.de/content/en/articles/news/2020/02/20200515_the-starlink-satellite-project.html

61) Jeff Foust, ”SpaceX to test Starlink “sun visor” to reduce brightness,” SpaceNews, 27 April 2020, URL: https://spacenews.com/spacex-to-test-starlink-sun-visor-to-reduce-brightness/

62) ”Killer asteroid hunt in jeopardy, new study claims,” Space Daily, 19 March 2020, URL: https://www.spacedaily.com/reports/Killer_asteroid_hunt_in_jeopardy_new_study_claims_999.html

63) Jonathan McDowell, ”The Low Earth Orbit Satellite Population and Impacts of the SpaceX Starlink Constellation,” Draft Version 16 March 2020, Submitted to ApJL (Astrophysical Journal), URL: https://planet4589.org/space/papers/starlink20.pdf

64) ”New ESO Study Evaluates Impact of Satellite Constellations on Astronomical Observations,” eso2004 Organization Release, 5 March 2020, URL: https://www.eso.org/public/news/eso2004/

65) Oliver R. Hainaut, Andrew P. Williams, ”Impact of satellite constellations on astronomical observations with ESO telescopes in the visible and infrared domains,” Astronomy & Astrophysics, 3 March 2020, https://doi.org/10.1051/0004-6361/202037501, URL: https://www.aanda.org
/articles/aa/pdf/forth/aa37501-20.pdf

66) Troy Farah, ”Light pollution from satellites will get worse. But how much?,” Nature Astronomy News, 14 June 2019, URL: http://www.astronomy.com/news/2019/06/
light-pollution-from-satellites-will-get-worse-but-how-much

67) Alexandra Witze, ”SpaceX tests black satellite to reduce ‘megaconstellation’ threat to astronomy — Latest launch includes ‘DarkSat’ prototype to reduce reflection from fleets of broadband Internet satellites,” Nature Astronomy News, 9 January 2020, URL: https://www.nature.com/articles/d41586-020-00041-4


The information compiled and edited in this article was provided by Herbert J. Kramer from his documentation of: ”Observation of the Earth and Its Environment: Survey of Missions and Sensors” (Springer Verlag) as well as many other sources after the publication of the 4th edition in 2002. - Comments and corrections to this article are always welcome for further updates (herb.kramer@gmx.net)

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