ISS Utilization: ECOSTRESS (ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station)
Background: In July 2014, NASA selected proposals from the second Earth Venture Instrument (EVI-2) Pathfinder Program for two new instruments that will observe changes in global vegetation from the International Space Station. The sensors will give scientists new ways to see how forests and ecosystems are affected by changes in climate or land use change. 1) 2) 3)
The new projects are:
• GEDI (Global Ecosystem Dynamics Investigation), a laser-based system from the University of Maryland, College Park, to observe the structure of forest canopy. This instrument is expected to be launched in 2019.
- Ralph Dubayah, of the University of Maryland, is the principal investigator for the GEDI Lidar. This project will use a laser-based system to study a range of climates, including the observation of the forest canopy structure over the tropics, and the tundra in high northern latitudes. This data will help scientists better understand the changes in natural carbon storage within the carbon cycle from both human-influenced activities and natural climate variations.
- The GEDI team has extensive experience in observing and modeling forest and vegetation dynamics. Dubayah has led numerous vegetation lidar observations from sub-orbital platforms throughout his career. The team includes partnerships with NASA's Goddard Space Flight Center, Greenbelt, Maryland; Woods Hole Research Center, Woods Hole, Massachusetts; the U.S. Forest Service, Ogden, Utah; and Brown University, Providence, Rhode Island.
• ECOSTRESS (ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station), a high-resolution multiple wavelength imaging spectrometer from NASA/JPL (Jet Propulsion Laboratory) in Pasadena, CA, to study the effectiveness of water use by vegetation.
- Simon Hook of JPL is the PI (Principal Investigator) for ECOSTRESS. This project will use a high-resolution thermal infrared radiometer to measure plant evapotranspiration, the loss of water from growing leaves and evaporation from the soil. These data will reveal how ecosystems change with climate and provide a critical link between the water cycle and effectiveness of plant growth, both natural and agricultural.
- The ECOSTRESS team has extensive experience in development and analysis of thermal infrared spectroscopic images of the Earth’s surface. Hook has served as project scientist for the ASTER (Advanced Spaceborne Thermal Emission Reflection Radiometer) instrument on NASA's Earth Observing System Terra satellite and has been involved in numerous sub-orbital field campaigns. The team includes partnerships with the U.S. Department of Agriculture, Beltsville, Maryland, and Maricopa, Arizona; Princeton University, Princeton, New Jersey; and University of Idaho, Moscow, Idaho.
The International Space Station provides several in-orbit capabilities useful to both instruments. The space station orbit is inclined relative to the poles, providing more observation time of forests and vegetation over temperate land masses than possible from the polar orbits commonly used for other types of Earth observations. The GEDI laser requires significant power resources, which the space station can provide. Also, the relatively low altitude of the station's orbit, about 400 km up, benefits GEDI by ensuring a higher return energy for laser pulses reflected from the ground.
NASA/LaRC (Langley Research Center) in Hampton, Virginia, manages the Earth System Science Pathfinder program for NASA's Science Mission Directorate. The missions in this program provide an innovative approach to address Earth science research with periodic windows of opportunity to accommodate new scientific priorities.
Figure 1: Two new spaceborne Earth-observing instruments will help scientists better understand how global forests and ecosystems are affected by changes in climate and land use change. This image of the Amazon rainforest is from a 2010 global map of the height of the world’s forests based on multiple satellite datasets (image credit: NASA Earth Observatory)
The NASA ECOSTRESS mission is one of two instruments chosen from the second EVI-2 (Earth Venture Instrument) Pathfinder Program AO (Announcement of Opportunity). With a launch scheduled for 2018, ECOSTRESS will assess vegetation water stress using a multispectral thermal instrument installed on the International Space Station. In the ISS orbit of ~ 400 km altitude and 51.6º inclination, ECOSTRESS will provide a repeat cycle of nearly three-days and a spatial resolution of ~ 60 m. Due to the unique orbital path of the ISS, ECOSTRESS will observe the same spot on Earth at different times each day. This configuration will enable an unprecedented view of diurnal trends in vegetation evapotranspiration, allowing the science community to address the following questions: 4) 5) 6)
• How does the terrestrial biosphere respond to changes in water availability?
• How do evapotranspiration and vegetation water stress interact with the global carbon cycle?
• How can scientists better understand agricultural vulnerabilities and drought impacts linked to vegetation water stress?
The ECOSTRESS mission will answer these questions by accurately measuring the temperature of plants. Plants regulate their temperature by releasing water through tiny pores on their leaves called stomata. If they have sufficient water they can maintain their temperature but if there is insufficient water their temperatures rise and this temperature rise can be measured with a sensor in space. ECOSTRESS will use a multispectral thermal infrared radiometer to measure the surface temperature that will be delivered to Houston for deployment on the International Space Station in 2018. The radiometer will acquire the most detailed temperature images of the surface ever acquired from space and will be able to measure the temperature of an individual farmers field.
Figure 2: Planned coverage of ECOSTRESS measurements (image credit: NASA/JPL)
One of the core products that will be produced by ECOSTRESS team is ESI (Evaporative Stress Index). ESI is a leading drought indicator - it can indicate that plants are stressed and that a drought is likely to occur providing the option for decision makers to take action. Figure 3 illustrates the ESI for the United States during the 2012 drought. The red areas indicate regions of high water stress.
Figure 3: Map of the 2012 drought in the United States showing differences in water stress. Red areas indicate high water stress (drought conditions) and green areas indication low water stress (non-drought conditions), image credit: NASA/JPL
Simon J. Hook of NASA/JPL is the PI of the ECOSTRESS instrument development and science investigation. The mission leverages the successful design, construction, and testing of the PHyTIR (Prototype HyspIRI Thermal Infrared Radiometer), which was initially developed to support testing and assessment for the HyspIRI (Hyperspectral Infrared Imager) under the auspices of ESTO (Earth Science Technology Office). ECOSTRESS consists of a cross-track, push-whiskbroom, scanning, multiband filter radiometer with five spectral bands between 8 and 12.5 µm, and a high spatial resolution of 38 m in-track by 69 m cross-track, and will be deployed on the JEM (Japanese Experiment Module) External Facility on the ISS. Because of the precessing orbit of the ISS, the ECOSTRESS will enable vegetation water stress assessments on a diurnal scale. 7)
The multispectral TIR (Thermal Infrared) instrument, mounted on the JEM-EF , will measure the brightness temperature of plants and use that information to better understand how much water plants need and how they respond to stress (evapotranspiration dynamics).
The ECOSTRESS instrument has a mass of ~465 kg, an average power consumption of ~527 W, a volume of 1.3 m3, an average data rate of 2.3 Mbit/s (nominally 4.5 Mbit/s) and a design life of 5 years. Typical revisit of 90% of CONUS every 4 days at varying times over the diurnal cycle.
The TIR instrument will acquire data from the ISS with a 38 m in-track by 68 m cross-track spatial resolution in five spectral bands, located in the TIR part of the electromagnetic spectrum between 8 and 12.5 µm. The positions of three of the TIR bands closely match the first three thermal bands of ASTER, while two of the TIR bands match bands of ASTER and MODIS typically used for split-window type applications (ASTER bands 12–14 and MODIS bands 31, 32). It is expected that small adjustments to the band positions will be made based on ongoing engineering filter performance capabilities. 10)
The TIR instrument will operate as a push-whisk mapper, similar to MODIS but with 256 pixels in the cross-whisk direction for each spectral channel (Figure 4), which enables a wide swath and high spatial resolution. As the ISS moves forward, the scan mirror sweeps the focal plane ground projection in the cross-track direction. Each sweep is 256-pixels wide. The different spectral bands are swept across a given point on the ground sequentially. From the 400±25 km ISS altitude, the resulting swath is 402 km wide. A wide continuous swath is produced even with an ISS yaw of up to ±18.5º. The scan mirror rotates at a constant angular speed. It sweeps the focal plane image 53º across nadir, then to two on-board blackbody targets at 300 K and 340 K. Both blackbodies will be viewed with each cross-track sweep every 1.29 seconds to provide gain and offset calibrations.
Figure 4: ECOSTRESS TIR scanning details (image credit: NASA/JPL)
Figure 5: Drawing of the ECOSTRESS radiometer in its container (image credit: NASA/JPL)
Figure 6: Overview of Earth science instruments on the ISS (installed or planned) in the second decade of the 21st century (image credit: NASA) 13)
In summary, ECOSTRESS will provide the highest spatial resolution thermal infrared data ever from the International Space Sta1on. HyspIRI (Hyperspectral Infrared Imager) is planned for the 2023+ timeframe.
• ECOSTRESS is possible because of the development of the PHyTIR (Prototype HyspIRI Thermal Infrared Radiometer) instrument for HyspIRI-TIR supported by ESTO
• ECOSTRESS will address a subset of the science associated with HyspIRI
• The ECOSTRESS mission will help answer three key science questions:
- How is the terrestrial biosphere responding to changes in water availability?
- How do changes in diurnal vegetation water stress impact the global carbon cycle?
- Can agricultural vulnerability be reduced through advanced monitoring of agricultural water consumptive use and improved drought es1ma1on?
• ECOSTRESS has a clearly defined set of data products and mature algorithms
• Opportunity for combined HyspIRI-like datasets using the European EnMAP and ECOSTRESS with GEDI (Global Ecosystems Dynamics Investigation Lidar) for structure.
• June 11, 2018: A new batch of science is headed to the International Space Station aboard the SpaceX Dragon on the company's 15th mission for commercial resupply services, scheduled for launch on 29 June from NASA's Kennedy Space Center in Florida. The spacecraft will deliver science that studies plant water use all over the planet, artificial intelligence, gut health in space, more efficient drug development and the formation of inorganic structures without the influence of Earth's gravity. 14)
Figure 7: A technician inspects NASA's ECOSTRESS instrument in a clean room at Kennedy Space Center in Florida. ECOSTRESS measures the temperature of plants, which shows how they are regulating their water use in response to heat stress (image credit: NASA/JPL-Caltech/KSC)
• April 30, 2018: ORR (Operational Readiness Review) at JPL (Jet Propulsion Laboratory).
• April 17, 2018: The ECOSTRESS instrument arrived at Kennedy Space Center on 9 April to begin final preparations for launch to the International Space Station this summer aboard a cargo resupply mission. 15)
- ECOSTRESS is expected to provide key insights into how plants link Earth's global carbon and water cycles. ECOSTRESS data will be used in conjunction with other satellite and ground measurements, such as those from NASA's Orbiting Carbon Observatory-2 satellite. By doing this, scientists hope to understand more clearly the total amount of carbon dioxide plants remove from the atmosphere during a typical day. In addition, they hope to better identify which areas on the planet require more or less water for the amount of carbon dioxide they take up.
- In practical terms, the year of data gleaned from ECOSTRESS will be useful for agricultural water managers. This data should improve our understanding of how certain regions are affected by drought and help agricultural and water management communities better manage water use for agriculture. The high ground spatial resolution of ECOSTRESS data will be useful for research on the effects of drought on agriculture at the field-scale.
Figure 8: ECOSTRESS arrives at Kennedy Space Center in preparation for launch to the space station this summer (image credit: NASA)
• May, 2016: JPL selected an upgraded Thales LPT9310 COTS (Commercial Off The Shelf) cryocooler for the ECOSTRESS instrument. The LPT9310’s proven reliability has resulted in interest from JPL in using this cooler for cost-sensitive space applications. This instrument provides nominally over 4 W of cooling capacity at 80 K. - However, this capability has only been proven in terrestrial (commercial) applications. In order to provide sufficient justification for using an off-the-shelf cooler for a flight application, additional tests have been performed on the delivered flight coolers, to attain a sufficiently controlled level of quality while leveraging the heritage of the COTS cooler. 16)
- A qualification test campaign was completed successfully, with the upgraded design meeting qualification-level robustness requirements after being subjected to fatigue cycling as well as providing the required efficiency increase. Flight models are currently in production and will be delivered to JPL July 2016.
Figure 9: Timeline of ECOSTRESS (image credit: NASA/JPL, Ref. 8)
Figure 10: Photo of the LPT9310 pulse tube cryocooler (image credit: Thales Cryogenics B. V.)
Figure 11: EM cryocooler installation for ECOSTRESS (image credit: NASA/JPL)
Figure 12: Japanese Experiment Module on International Space Station (image credit: NASA)
Launch: The ECOSTRESS instrument was launched on 29 June 2018 on the SpX-15 logistics flight (Dragon trunk) of SpaceX. The launch site was the Cape Canaveral Air Force Station, FL and the launch vehicle is a Falcon-9 v1.2. 17) 18) 19)
Orbit: Near-circular orbit of the ISS, altitude of ~400 km, inclination = 51.6º, period = 93 minutes.
The ECOSTRESS instrument will be mounted onto the JEM-EF (Exposed Facility) site 10 of JAXA. At this location, the radiometer scan is perpendicular to the ISS velocity.
Science instruments on the SpaceX CRS-15 logistics flight: (Ref. 14)
1) ECOSTRESS of NASA/JPL. measures the temperature of plants and uses that information to better understand how much water plants need and how they respond to stress.
2) Mobile Companion, an ESA (European Space Agency) investigation, also known as CIMON (Crew Interactive Mobile Companion), explores the use of AI as a way to mitigate crew stress and workload during long-term spaceflight.
3) Rodent Research-7 takes a look at how the microgravity environment of space affects the community of microoganisms in the gastrointestinal tract, or microbiota.
4) Angiex Cancer Therapy examines whether microgravity-cultured endothelial cells represent a valid in vitro model to test effects of vascular-targeted agents on normal blood vessels.
5) Chemical Gardens are structures that grow during the interaction of metal salt solutions with silicates, carbonates or other selected anions. Their growth characteristics and attractive final shapes form from a complex interplay between reaction-diffusion processes and self-organization.
These investigations join hundreds of others currently happening aboard the orbiting laboratory.
• Project Biarri Squad 1-3 technology demonstration: The Biarri project is a four nation defence related project involving Australia, the US, the UK and Canada to build three 3U CubeSats for precision formation flying experiments and a risk mitigation satellite.
• Bhutan-1, a 1U CubeSat: Bhutan, along with Malaysia and the Philippines, is currently participating in the second joint global multi-nations BIRDS Project called BIRDS-2, initiated by KIT (Kyutech Institute of Technology), Japan, which is represented by four engineers from the telecom and space division of the information and communications ministry (MoIC).
• MAYA-1, the first Filipino 1U CubeSat implemented by the PHL-Microsat Program of the University of the Philippines Diliman, in collaboration with the DOST-ASTI (Department of Science and Technology - Advanced Science and Technology Institute) and the KIT (Kyushu Institute of Technology), Japan. The development of the Maya-1 falls under BIRDS-2 (Birds Satellite Project; note: the BIRDS-2 CubeSats are Bhutan-1, MAYA-1 and UiTMSAT-1), a cross-border interdisciplinary satellite project that accommodates non-space faring countries.
• UiTMSAT-1, a 1U CubeSat of Malaysia. JAXA arranged for the testing and the launch of the BIRDS-2 CubeSats to the ISS.
• August 19, 2020: As record temperatures and large wildfires scorch California, NASA's Ecosystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) has been tracking the heat wave from low Earth orbit. While ECOSTRESS's primary mission is to measure the temperature of plants heating up as they run out of water, it can also measure and track heat-related phenomena like heat waves, wildfires, and volcanoes. 20)
- At 3:56 p.m. PDT (6:56 p.m. EDT) on Aug. 14, as the space station passed over Los Angeles, ECOSTRESS was able to take a snapshot of the soaring land surface temperatures across the county, home to more than 10 million people. (Land surface temperature is the temperature of the ground rather than the air above it.) In the first image, ECOSTRESS measured a temperature range of about 70-125 degrees Fahrenheit (21-52 degrees Celsius), with the coolest being at the coasts and mountains. The highest surface temperatures, in dark red, were found northwest of downtown Los Angeles in the San Fernando Valley. (The instrument also captured the Ranch fire, seen in the center of the image, as it burned.) Land surface temperatures there reached over 125 degrees Fahrenheit (52 degrees Celsius), with a peak of 128.3 degrees Fahrenheit (53.5 degrees Celsius) between the cities of Van Nuys and Encino.
- Those afternoon peaks were within range of morning surface temperatures ECOSTRESS gauged two days later in Death Valley, part of California's Mojave Desert. As shown in the second image, from Aug. 16 at 8:50 a.m. PDT (11:50 a.m. EDT), ECOSTRESS recorded a maximum temperature of 122.52 degrees Fahrenheit (50.29 degrees Celsius) near Furnace Creek in Death Valley National Park.
Figure 13: This ECOSTRESS temperature map shows the land surface temperatures throughout Los Angeles County on Aug. 14, 2020, during a heat wave (image credit: NASA/JPL-Caltech)
- ECOSTRESS observations have a spatial resolution of about 70 x 70 m, which enables researchers to study surface-temperature conditions down to the size of a football field. Due to the space station's unique orbit, the mission can acquire images of the same regions at different times of day, as opposed to crossing over each area at the same time of day like satellites in other orbits do. This is advantageous when monitoring plant stress in the same area throughout the day, for example.
• August 3, 2020: NASA's ECOSTRESS captured a birds-eye view of the vast Apple fire raging in Southern California. 21)
- The wildfire began on the evening of Friday, July 31, after two smaller fires merged and rapidly grew in the hot conditions in Riverside County, east of Los Angeles, prompting the evacuation of thousands of residents. Air temperatures have soared past 100 degrees Fahrenheit (38 degrees Celsius), stressing the vegetation and turning the area into a tinderbox. By Monday, the wildfire had exploded to over 26,000 acres.
- ECOSTRESS recorded the image above at 1:15 p.m. PST (4:15 p.m. EDT) on Saturday, Aug. 1, 2020, when the burn area was approximately 4,000 acres in size. In the image, the black smoke plume can be seen drifting east and over Joshua Tree National Park in the Mojave Desert. With a spatial resolution of about 77 by 77 yards (70 x 70 m), the image enables researchers to study surface-temperature conditions down to the size of a football field. In the active burn area, temperatures of between 390 and 1290 degrees Fahrenheit (200 and 700 ºC) were recorded, and in one pixel in the ECOSTRESS image of the burn zone, a peak temperature of 1387 degrees Fahrenheit (753ºC) was detected.
- Tasked with detecting plant water use and stress, ECOSTRESS's primary mission is to measure the temperature of plants heating up as they run out of water. But it can also measure and track heat-related phenomena like fires, heat waves, and volcanoes. Due to the space station's unique orbit, the mission can acquire images of the same regions at different times of the day, as opposed to crossing over each area at the same time of day like satellites in other orbits do. This is advantageous when monitoring plant stress in the same area throughout the day, for example.
Figure 14: This temperature map shows the stressed and dry vegetation surrounding the Apple fire in Southern California on Aug. 1, 2020. The observation was made possible by NASA's ECOSTRESS that measured the temperature of the burn area and tracked the dark smoke plume drifting east from California to Arizona (image credit: NASA/JPL-Caltech)
• February 26, 2020: Although plants do not sleep in the same way that humans do, they do have more and less active times and they have circadian rhythms—internal clocks that tell them when it is night and when it is day. And like many people, plants are less active at night. When the Sun comes up, however, they awake to the day. An instrument mounted on the International Space Station can see this leafy wake-up call. 22)
- Plants absorb sunlight to convert carbon dioxide and water into food, a process called photosynthesis. They also “sweat” excess water through pores in their leaves to cool themselves down, a process called evapotranspiration. NASA’s Ecosystem Spaceborne Thermal Radiometer on Space Station (ECOSTRESS) instrument has observed plants beginning these processes in the morning.
- Mounted on the outside of the International Space Station, ECOSTRESS provides insight into the health of vegetation by essentially taking its temperature. Using a radiometer to measure the thermal infrared energy emitted by plants, ECOSTRESS can measure how much they are transpiring and how they are responding to weather and climate stresses.
Figure 15: These images, built from ECOSTRESS data, show plants waking up west of Lake Superior, near the U.S.–Canada border. Each color (red/orange, blue, and purple) represents the time (7, 8, and 9 a.m.) when plants and trees were observed to start transpiring. The darker the shading, the more intense the transpiration activity. The images were acquired in the period 1 June to August 30, 2019 (image credit: NASA Earth Observatory images by Lauren Dauphin, using evaporative stress data from the ECOSTRESS team. Story by Esprit Smith, NASA’s Earth Science News team, with Mike Carlowicz)
- The space station’s unique orbit enables ECOSTRESS to capture data over the same areas of Earth at different times of day. For the wake-up observations, scientists team collected and averaged all of their morning observations in the region from June 1 to August 30, 2019. In doing so, they observed that the earliest risers were near the lake, with plant activity spreading gradually northwestward as the morning progressed.
- The ability to detect plant behavior in this way could be especially helpful to resource managers and farmers, who might use the data to determine how much water their crops need, which ones are most water-efficient, and which ones are not getting enough water—even before plants show visible signs of dehydration. The instrument can provide such data on a global scale and within areas as small as a football field.
Figure 16: This image shows what the study area looks like at midday to most visible light satellite sensors. It was acquired by the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Aqua satellite on July 30, 2019 (image credit: NASA Earth Observatory, image by Lauren Dauphin, using MODIS data from NASA EOSDIS/LANCE and GIBS/Worldview . Story by Esprit Smith, NASA’s Earth Science News team, with Mike Carlowicz)
• February 4, 2020: Although plants don't sleep in the same way humans do, they have circadian rhythms - internal clocks that, like our own internal clocks, tell them when it's night and when it's day. And like many people, plants are less active at night. When the Sun comes up, they kick into gear, absorbing sunlight to convert carbon dioxide they draw from the air and water they draw from the soil into food, a process called photosynthesis. They also "sweat" excess water through pores on their leaves to cool themselves down, a process called evapotranspiration. 23)
- NASA's ECOSTRESS (ECOsystem Spaceborne Thermal Radiometer on Space Station) instrument can see when plants "wake up" and begin these processes from space. The image of Figure 17 shows plants waking up (as evidenced by evapotranspiration) west of Lake Superior near the U.S.-Canada border. Plants in the red and pink areas began to awake at around 7 a.m. local time. Those in green areas awoke closer to 8 a.m., and those in blue areas, closer to 9 a.m.
- ECOSTRESS launched to the International Space Station in June 2018. The space station's unique orbit enables the instrument to capture data over the same areas at different times of day. When the mission team analyzes the data, they gain new insight into how plants behave throughout the course of a day.
- For this image, the mission team collected and combined all of ECOSTRESS's morning data for the summer season. In doing so, they observed that the earliest risers were near the lake, with plant activity spreading gradually northwestward as the morning progressed.
- ECOSTRESS' ability to detect plant behavior in this way can be especially helpful to resource managers and farmers, who can use the data to determine how much water their crops need, which ones are most water-efficient and which ones aren't getting enough water, even before they show visible signs of dehydration. What's more, the instrument can provide this data on a global scale over areas as small as a football field.
- NASA's Jet Propulsion Laboratory in Pasadena, California, built and manages the ECOSTRESS mission for the Earth Science Division in the Science Mission Directorate at NASA Headquarters in Washington. ECOSTRESS is an Earth Venture Instrument mission; the program is managed by NASA's Earth System Science Pathfinder program at NASA's Langley Research Center in Hampton, Virginia.
Figure 17: Like many people, plants are less active at night. The agency's 'space botanist' can see when they begin to stir, and start their day. The image shows plants "waking up" near Lake Superior. Red areas began to wake up at around 7 a.m. local time; green areas awoke around 8 a.m.; and blue areas, at about 9 a.m. The data was acquired by ECOSTRESS during the summer season (image credit: NASA/JPL-Caltech)
• November 5, 2019: A new satellite-based map of a section of the Amazon Basin reveals that at least some of the massive fires burning there this past summer were concentrated in water-stressed areas of the rainforest. The stressed plants released measurably less water vapor into the air than unstressed plants; in other words, they were struggling to stay cool and conserve water, leaving them more vulnerable to the fires. 24)
- The fires in the Amazon Basin, which continue to burn into November, are mainly the result of such human activities as land clearing and deforestation. The pattern - spotted from space by NASA's ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) - points to how water-stressed plants can impact the spread of fires. The data may one day help NASA's Earth-observing missions predict the path of future forest or brush fires like those currently raging in California.
- The primary mission of ECOSTRESS, an instrument that measures thermal infrared energy emitted from the land surface, is to provide insight into plants' health by taking their temperature. To keep cool, plants "sweat" by releasing water vapor through their pores, a process called evapotranspiration. After multiple orbits, ECOSTRESS is able to measure how much plants transpire and track their response to climate change.
- In August, fires spread over large swaths of the Amazon Basin. ECOSTRESS captured the first image of the Amazon rainforest in Peru before the fires began, on Aug. 7. It shows a surface temperature map revealing water-stressed and non-stressed forest (shown in brown and blue, respectively). The fire icons represent fires imaged by NASA's Terra satellite between Aug. 19 and 26. The fires are limited primarily to areas of water-stressed plants that transpired the least. The second image, taken by the Terra satellite on Aug. 18, shows the ECOSTRESS study area and smoke from active fires in the rainforest.
Figure 18: NASA's ECOSTRESS sensor measured the water-stress levels of plants when it passed over the Peruvian Amazon rainforest on Aug. 7, 2019, before the fires there began. The map shows areas of plants in distress (brown) and areas of less stress (blue). Water-stressed plants released measurably less water vapor into the air at the time of the summer fires. The fire icons represent fires imaged by NASA's Terra satellite between Aug. 19 and 26. The burn pattern reveals that the fires were concentrated in areas of highly water-stressed plants, pointing to how water-stressed plants can impact the spread of fires. The data may one day help NASA's Earth-observing missions predict the path of future forest or brush fires (image credit: NASA/JPL-Caltech/Earth Observatory)
- The image also reveals how certain parts of the forest were more resilient, seeming to protect themselves from burning. Plants in these areas were cooler - in other words, they released more water vapor from their leaves - than plants in the burn zones, though mission scientists don't know whether that's a coincidence or a direct causal relationship. The water-stressed areas of the forest look as green and healthy as these cooler areas, making them invisible except to a radiometer that can measure thermal infrared energy from the surface.
- "To the naked eye, the fires appear randomly distributed throughout the forest," said Josh Fisher, ECOSTRESS science lead at NASA's Jet Propulsion Laboratory in Pasadena, California. "But, if you overlay the ECOSTRESS data, you can see that the fires are mainly confined within the highly water-stressed areas. The fires avoided the low-stress areas where the forest appears to have access to more water."
- It's still a mystery why some plants become stressed while other plants don't, though scientists believe it's dependent on factors like the species of plant or amount of water in the soil. The data from ECOSTRESS will help answer questions about which plants will thrive in their changing environments and could also be used to help with decisions related to water management and agricultural irrigation.
• On August 30, 2019, the ECOSTRESS team received official guidance that the ECOSTRESS mission would be extended for a second year. A special thank you to the Early Adopters / Community of Practice for helping us and NASA understand all the ways ECOSTRESS data can be applied and for all of your feedback throughout this mission thus far.
• August 8, 2019: NASA's ECOSTRESS has imaged the stress on Costa Rican vegetation caused by a massive regional drought that led the Central American nation's government to declare a state of emergency on July 23. 25)
- Parts of Costa Rica have received 75% less rainfall than normal in the drought, which is the result of abnormal weather patterns accompanying an El Niño that began in November 2018. The drought's effects were already visible to ECOSTRESS in February 2019, as the image shows.
- Launched to the International Space Station in June 2018, ECOSTRESS measures the temperature of plants as they heat up when they run out of water. A key benefit of the instrument, in addition to providing information on surface temperature and plant water use, is its ability to detect droughts as they stress plants.
- In Costa Rica, more intense drought conditions - shown in red colors in this image - are centered on the province of Guanacaste, part of a Central American tropical dry forest region called the Dry Corridor that is particularly sensitive to droughts. Normally very cloudy, Guanacaste had few clouds (appearing in light gray) when ECOSTRESS acquired this image.
- ECOSTRESS measures variations in ground temperatures to within a few tenths of a degree and is able to detect temperature changes at various times of day over areas as small as a single farm. These measurements help scientists assess how healthy plants are and how they respond to water shortages. Not only can the measurements be an indicator of future drought, they can also be used in observing heat trends, spotting wildfires and detecting volcanic activity.
- ECOSTRESS provides a wide range of image products for studying the land surface and recently made all these products publicly available through the NASA Land Processes Distributed Active Archive Center (LPDAAC).
Figure 19: This image shows the ECOSTRESS evaporative stress index for the Guanacaste region of Costa Rica (in red on inset map, left) a few months after the onset of a major Central American drought. Red indicates high plant water stress, yellow is moderate stress and greens/blues are low stress. Light gray is cloud cover. The index measures how much water plants are using relative to how much they would use under optimal conditions; low numbers correlate with high stress (image credit: NASA/JPL-Caltech)
• July 2, 2019: Europe's massive heat wave is on its way out - and it's leaving a slew of broken temperature records in its wake. Many countries were gripped by temperatures above 104º Fahrenheit (40 º C) between June 26 and June 30. According to the WMO (World Meteorological Organization), June 2019 is now the hottest month on record for the continent as a whole. 26)
- NASA's Ecosystem Spaceborne Thermal Radiometer Experiment on Space Station (ECOSTRESS) measures Earth's surface temperature from the International Space Station at different times of day. Although its primary objective is to monitor the health of plants, ECOSTRESS can also detect heat events such as the one much of Europe just experienced.
- ECOSTRESS mapped the surface, or ground temperature, of four European cities - Rome, Paris, Madrid and Milan - during the mornings of June 27 and June 28.In the images, hotter temperatures appear in red and cooler temperatures appear in blue. They show how the central core of each city is much hotter than the surrounding natural landscape due to the urban heat island effect - a result of urban surfaces storing and re-radiating heat throughout the day.
- The fact that surface temperatures were as high as 25-30º Celsius in the early morning indicates that much of the heat from previous days was stored by surfaces with high heat capacity (such as asphalt, concrete and water bodies) and unable to dissipate before the next day. The trapped heat resulted in even higher midday temperatures, in the high 40s (Celsius) in some places, as the heat wave continued.
- ECOSTRESS launched to the space station last summer and began collecting its first heat data just days after installation. The instrument measures variations of ground temperatures to within a few tenths of a degree, and it does so with unprecedented detail: It's able to detect temperature changes at various times of day over areas the size of a football field. These measurements help scientists assess plant health and response to water shortages, which can be an indicator of future drought. They can also be used in observing heat trends, spotting wildfires and detecting volcanic activity.
Figure 20: These maps of four European cities show ECOSTRESS surface temperature images acquired in the early mornings of June 27 and 28, 2019, during a heatwave. The images have been sharpened to delineate key features such as airports. Airports and city centers are hotter than surrounding regions because they have more surfaces that retain heat (asphalt, concrete, etc.), image credit: NASA/JPL-Caltech
- ECOSTRESS provides a wide range of image products for studying the land surface and recently made all these products publicly available through the NASA Land Processes Distributed Active Archive Center (LPDAAC).
- JPL built and manages the ECOSTRESS mission for NASA's Earth Science Division in the Science Mission Directorate at NASA Headquarters in Washington. ECOSTRESS is an Earth Venture Instrument mission; the program is managed by NASA's Earth System Science Pathfinder program at NASA's Langley Research Center in Hampton, Virginia.
• March 6, 2019: Farmers irrigating their crops may soon be getting some help from space. In 2018, scientists launched ECOSTRESS, a new instrument now attached to the International Space Station. Its mission: to gather data on how plants use water across the world. ECOSTRESS helps scientists answer three broad questions: 27)
a) How do plants respond to drought?
b) What’s happening with plants’ water use over the course of a day?
c) Can vulnerability to drought be reduced through more monitoring?
- “Technically, the instruments are measuring surface temperature, which reflects the heat stress of plants,” explains Joshua Fisher of NASA’s Jet Propulsion Laboratory. Fisher is the science lead on the ECOSTRESS mission. “By measuring the temperature, we are able to tell how much water plants are using. For example, if you have two plants and water one, the one that has more water will be cooler.”
- The temperature measurement can be compared to holding a hand over hot sand at the beach. Even without touching the sand, a person can tell it’s hot. That’s the kind of energy ECOSTRESS picks up.
- And the system is taking measurements at various times of day, thanks to the Space Station’s unique orbit. That’s important: Plants function differently throughout the day.
- When plants have enough water, they open pores in their leaves (the stomata) to take up carbon dioxide for photosynthesis. When opening the stomata, the plant loses water. However, a water-stressed plant, even before a full drought, will protectively close the stomata to conserve water. While the plant retains precious water, it also cools off less.
- Using the temperature data from ECOSTRESS, scientists are able to calculate evapotranspiration—the amount of water evaporating from the surface of the Earth and from plants. “And for farmers, this information is the number one requirement for irrigation. It’s useful for them to know how much to water plants. And it helps indicate future droughts and weather changes.”
- Having this kind of information can tell researchers how much water is going up into the atmosphere and also how much energy is being used to do that. It can also show which plants are being more efficient with their water and which are stressed because they don’t have enough. It can do this on a surprisingly small scale: down to 230 square feet (20 m2).
- “We are working with water managers and agricultural specialists who want these data so they can get them to the farmers they work with,” Fisher says. “We have a whole office at NASA that connects societal users with our data so it can be used to help farmers and others make better decisions.”
- The project is an international collaboration. Astronauts performed a six-hour spacewalk to prepare for ECOSTRESS to arrive. A Canadian robotic arm took ECOSTRESS off its cargo spacecraft and passed it to the Japanese robotic arm for installation. ECOSTRESS uses the space station’s power and communications to collect data and send it down to Fisher and his team.
- “This was the first launch I went to and it was really something special,” Fisher says. “I got interested in this work after growing up splitting time between Los Angeles and Alaska and thinking about a bigger vision of how life on Earth persists and thrives. Evapotranspiration is the number one climatic predictor of biodiversity. When you have a lot of water and energy, you have a lot of life.”
• October 5, 2018: Did you ever notice how the air can seem cooler when you enter a forest? Humans aren’t the only living things that sweat to cool off. When trees and plants “sweat,” they cool themselves and can cool the surrounding air. Through a process called transpiration,water and nutrients are taken up by plant roots from soil and delivered to the stem and leaves as part of photosynthesis. Some of the water drawn up through the roots exits the plant through pores – or stomata—in its leaves, hence the sweating. As this ”sweat” evaporates, heat is removed from the air, providing a cooling effect. However, if there isn’t enough water available or if relative humidity gets too high, the stomata close. The plant heats up, ceases to grow, and can eventually die. 28)
Figure 21: NASA's ECOSTRESS mission is studying how plants sweat, providing detailed measurements of plant temperatures from space (video credit: Science@NASA, 5 October 2018)
- Healthy plants provide a number of ecosystem services to humans including food, recreation, and building materials. Plants also impact Earth's global water and carbon cycles, with plant transpiration accounting for around 10 percent of the moisture in our atmosphere. A new NASA mission called ECOSTRESS was successfully launched to the International Space Station on June 29th, 2018. ECOSTRESS will literally study how plants sweat, providing the most detailed measurements of plant temperatures available from space and helping researchers monitor the health of Earth’s vegetation.
- “Your temperature is one of the first things a doctor wants to know when you go for a checkup,” says Simon Hook, ECOSTRESS Principal Investigator from NASA’s Jet Propulsion Laboratory. “It tells your doctor a lot about your condition. Temperature is an extremely useful indicator for plants too.”
- “Temperature data can indicate if a plant is stressed and needs more water before the plant collapses, providing an early warning of a possible drought” explains Hook. “ECOSTRESS will be able to measure plant temperatures – and therefore plant health – over areas as small as an individual field of crops.”
- The International Space Station is well-suited for the ECOSTRESS mission. Hook says, “Most Earth observing satellites are in a Sun-synchronous orbit, so they pass over an area at the same time each day, providing us a daily snapshot of that area. Because of the space station’s orbit, ECOSTRESS sees the same spot on Earth every few days at different times of day so it can track changes throughout a typical day.”
- If, during a hot, dry afternoon, plants stop releasing water to conserve supplies, ECOSTRESS will “see” a change in temperature compared with previous measurements of the same area. It will detect these kinds of responses in farmer’s fields and other ecosystems. Data acquired from ECOSTRESS may, in time, help farmers develop crop watering protocols, give researchers a clearer understanding of the effects of drought, and assist water resource managers in planning effective water use. Its data could also reveal the effects of droughts on natural vegetation; for example, to help identify vulnerable types of trees. Forest managers and ecologists will be able to use this information to make better-informed decisions.
- But that’s not all. “ECOSTRESS temperature data will be useful in a whole host of ways,” says Hook. “We’ll be able to use the same techniques developed to extract plant temperature to look at other phenomena such as the temperature of volcanoes, urban heat waves, wildfires, coastal currents, lakes, and more. That’s a whole story in itself.”
• September 18, 2018: NASA's ECOSTRESS captured new imagery of variations in surface-temperature patterns in Los Angeles County. The first of its kind to be taken by the agency's newest Earth-observing mission, it is more detailed than previous imagery and, unlike prior imagery, was acquired at different times of the day. 29)
- ECOSTRESS measures surface temperature — the temperature you would feel if you touched the surface of something — rather than the air temperature typically reported by weather stations. The images were acquired throughout the day between 22 July 22 and 14 August during an extended period of high temperatures in the Los Angeles area.
- Cooler temperatures appear in blue, and warmer temperatures are shown in red. In the image taken July 22 at 4:07 a.m., the hottest (reddest) areas are dark asphalt surfaces that are unshaded during the day and remain warm throughout the night. They include freeways, airports, oil refineries and parking lots. The cool (blue) areas are clouds and higher-elevation mountainous regions (dark blue).
Figure 22: ECOSTRESS captured surface temperature variations in Los Angeles, CA in the early morning hours of July 22. Hot areas are shown in red, warm areas in orange and yellow, and cooler areas in blue (image credit: NASA/JPL-Caltech)
- The other images show how different urban surfaces warm up and cool down throughout the day. The daytime image (upper left) acquired at 3:01 p.m. PDT on July 31 shows how hot the inland regions can get during a period of extreme heat. The Santa Anita racetrack parking lot was the hottest area. At 147.3° F, the surface temperature there was hot enough to fry an egg.
Figure 23: ECOSTRESS imagery shows surface temperature variations in Los Angeles, California between July 22 and August 14 at different times of day. Hot areas are shown in red, warm areas in orange and yellow, and cooler areas in blue (image credit: NASA/JPL-Caltech)
Legend to Figure 23: The images in the upper right, lower left and lower right — acquired at 9:26 p.m., 11:43 p.m. and 4:07 a.m., respectively — show how urban surfaces cool down, with roof surfaces cooling at a much faster rate than roads and other asphalt surfaces that have a higher heat capacity. Note that in the lower-right image, reds correspond with temperatures in the 80s. The top image from the same time shows a slightly different scale to enhance the contrast between different surfaces — and reds correspond with temperatures in the 70s.
The Los Angeles area is known for its Mediterranean climate and abundant sunshine but also for its extreme "micro-climate" temperature swings — from cooler coastal areas to much warmer inland regions like the San Gabriel Valley. ECOSTRESS can detect the distribution and pattern variations of that surface heat over areas the size of a football field.
• August 2, 2018: ECOSTRESS, NASA's new Earth-observing mission aboard the ISS, has captured new imagery of three wildfires burning in California and Nevada — the first image of its kind to be taken by the agency's newest Earth-observing mission. 30)
- Surface temperatures above 32 degrees Celsius are shown in red, highlighting the burning areas along the fire fronts. Zooming in on the Carr and Perry fires shows the heat data in more detail, and also the very distinct smoke plumes the fires are producing. The measurements have a ground resolution of 70 m by 70 m.
- The Carr Fire, one of the largest of more than a dozen fires burning in California,started on July 23. As of August 2, the fire had grown to over 121,000 acres (48966 hectares). The Whaleback Fire started near Spalding, California on July 27 and spanned nearly 19,000 acres (7690 hectares) on August 2. The Perry Fire, which started just north of Reno, Nevada on July 27, had engulfed more than 49,000 acres (19830 hectares) as of August 2.
Figure 24: This ECOSTRESS image, acquired on July 28, shows three wildfires burning in the western US (in red) — the Carr and Whaleback fires in California, and the Perry Fire in Nevada (image credit: NASA/JPL-Caltech)
• July 23, 2018: Just days after its successful installation on the International Space Station, NASA's newest Earth-observing mission, ECOSTRESS (ECOsystem Spaceborne Thermal Radiometer Experiment on Space Station), has collected its first science data on Earth's surface temperature. 31)
- ECOSTRESS will measure the temperature of plants from space, enabling researchers to determine how much water plants use and to study how droughts affect plant health.
- The instrument was launched June 29 from Florida's Cape Canaveral Air Force Station on a SpaceX cargo resupply mission. It rode to orbit in the "trunk" of SpaceX's Dragon spacecraft, which berthed at the station on July 2. On July 5, ground controllers at NASA's Johnson Space Center in Houston extracted ECOSTRESS from the trunk, robotically transferred it to the station's Japanese Experiment Module - Exposed Facility (JEM-EF) and installed it. After a few days of testing and start-up activities, ECOSTRESS acquired its first-light image on 9 July.
- "Often satellite missions require weeks or months to produce data of the quality that we are already getting from ECOSTRESS," said the mission's principal investigator, Simon Hook of NASA's Jet Propulsion Laboratory in Pasadena, California. ECOSTRESS is one of a new class of low-cost, rapid-development NASA science instruments. The ECOSTRESS instrument was launched less than four years after the project was started.
- The ECOSTRESS team is now checking out the instrument and acquiring preliminary science data, a process expected to take about a month. They have completed an initial calibration of the science data and are now validating the data by comparing them with similar measurements made at ground control sites. When this process is complete, ECOSTRESS will be ready to begin its one-year science mission.
Figure 25: ECOSTRESS acquired this image the night of July 9, 2018, over Egypt. Yellow and red indicate generally higher temperatures. The River Nile is visible as a thin blue line on the main image. The black-and-white inset shows the level of detail available from ECOSTRESS, with the relatively cool Nile River and surrounding vegetation appearing darker (image credit: NASA/JPL)
• July 6,2018: NASA's ECOSTRESS was removed from the Dragon spacecraft and robotically installed on the exterior of the space station's Japanese Experiment Module -Exposed Facility (JEM-EF) late Thursday, July 5. Functional testing is expected to begin next week (update of Ref. 17).
Figure 26: NASA's new Earth-observing experiment, ECOSTRESS, is installed on the International Space Station. ECOSTRESS will provide thermal infrared measurements of Earth's surface allowing scientists to assess plant water use and response to changes in water availability (image credit: NASA)
• On 2 July 2018, the Dragon spacecraft was berthed to the Node-2/Harmony’s Nadir (Earth-facing) Common Berthing Mechanism of the ISS. 32)
Figure 27: ISS configuration on 2 July 2018: Five spaceships are attached to the space station including the SpaceX Dragon and Cygnus resupply ships from the United States; and from Roscosmos, the Progress 69 resupply ship and the Soyuz MS-08 and MS-09 crew ships (image credit: NASA) 33)
Steve Cole, “NASA Selects Instruments to Track Climate Impact on
Vegetation,” NASA, Release 14-199, July 30, 2014, URL: https://www.nasa.gov/press/2014/july/
2) Alan Buis, “NASA's ECOSTRESS Will Monitor Plant Health,” NASA, October 27, 2014, URL: https://www.nasa.gov/jpl/nasas-ecostress-will-monitor-plant-health/#.VYaMh0Y_PRI
3) Lacey Young, Alan Buis, ”New NASA Insights into the Secret Lives of Plants,” NASA/JPL, Nov. 2017, URL: https://www.jpl.nasa.gov/news/news.php?release=2017-298
4) Christine M. Lee,Joshua B. Fisher, Simon J. Hook, ”ECOSTRESS Science Team Meeting,” NASA, The Earth Observer, March-April 2016, Volume 28, Issue 2, p. 24, URL: http://eospso.nasa.gov/sites/default/files/eo_pdfs/Mar_Apr_2016_508_color.pdf
Christine M. Lee,Joshua B. Fisher, Simon J. Hook, ”ECOSTRESS
Science Team Meeting,” NASA, The Earth Observer, May-June 2015,
Volume 27, Issue 3, URL: http://ecostress.jpl.nasa.gov/downloads/science_team_meetings
8) Wes Schmitigal, ”ECOSTRESS Payload,” 2017 ECOSTRESS Science Team Meeting, 15 - 17 May 2017, URL: https://ecostress.jpl.nasa.gov/downloads/science_team_meetings
William R. Johnson, ”ECOSTRESS Instrument Performance,”
2017 ECOSTRESS Science Team Meeting, 15 - 17 May 2017, URL: https://ecostress.jpl.nasa.gov/downloads
10) Glynn Hulley, Simon Hook, Joshua Fisher, Christine Lee, ”ECOSTRESS, a NASA Earth-Ventures instrument for studying links between the water cycle and plant health over the diurnal cycle,” Proceedings of IGARSS 2017 (IEEE International Geoscience and Remote Sensing Symposium), Fort Worth, Texas, USA, July 23–28, 2017
11) Simon J. Hook and the HyspIRI and ECOSTRESS Teams, ”ECOSTRESS Update,” JPL/ Caltech, June 1, 2016, URL: https://hyspiri.jpl.nasa.gov/downloads
Simon J. Hook and the ECOSTRESS Team, ”ECOSTRESS (ECOsystem
Spaceborne Thermal Radiometer Experiment on Space Station)
Overview,” 2017 ECOSTRESS Science Team Meeting, 15 - 17 May 2017,
13) Julie A. Robinson, William L. Stefanov,”Earth Science Research on the International Space Station,” Committee on Earth Science and Applications from Space (CESAS) Space Studies Board National Academies of Science, Engineering, Medicine, 29 March 2016, URL: http://sites.nationalacademies.org/cs/groups/ssbsite/documents/webpage/ssb_171788.pdf
14) ”ECOSTRESS Among Science Payloads on Next Space Station Mission,” NASA/JPL, 12 June 2018, URL: https://www.jpl.nasa.gov/news/news.php?feature=7157&utm_source=iContact&
15) ”NASA's New Space 'Botanist' Arrives at Launch Site,” NASA/JPL News, 17 April 2018, URL: https://www.jpl.nasa.gov/news/news.php?release=2018-073
R. Arts, J. Mullié, D. Johnson, I. McKinley, J. Rodriguez, T.
Benschop, ”LPT9310 COTS cooler for ECOSTRESS,” ICC
(International Conference on Communications), Kuala Lumpur, Malaysia,
May 23-27, 2016 , URL: http://www.thales-cryogenics.com/wp-content/uploads
17) ”ECOSTRESS Launches to Space Station on SpaceX Mission,” NASA/JPL, 29 June 2018, URL: https://www.jpl.nasa.gov/news/news.php?feature=7179
18) ”CRS-15 Dragon Resupply Mission,” SpaceX, 29 june, 2018, URL: http://www.spacex.com/sites/spacex/files/crs15presskit.pdf
19) US Commercial ELV launch manifest, 6 March 2018, URL: http://www.sworld.com.au/steven/space/uscom-man.txt
20) ”NASA's ECOSTRESS Monitors California's Record-Breaking Heat Wave,” NASA/JPL, 19 August 2020, URL: https://www.jpl.nasa.gov/news/news.php?release=2020-161
21) ”NASA's ECOSTRESS Monitors California's Apple Fire From Space,” NASA/JPL, 3 August 2020, URL: https://www.jpl.nasa.gov/news/news.php?release=2020-152
22) ”ECOSTRESS Sees Plants Waking Up,” NASA Earth Observatory, 26 February 2020, URL: https://earthobservatory.nasa.gov
23) Esprit Smith, NASA's Earth Science News team, ”NASA's ECOSTRESS Mission Sees Plants 'Waking Up' From Space,” NASA/JPL News, 4 February 2020: URL: https://www.jpl.nasa.gov/news/news.php?release=2020-023
24) ”Drought-Stressed Forest Fueled Amazon Fires,” NASA/JPL News, 5 November 2019, URL: https://www.jpl.nasa.gov/news/news.php?feature=7534&utm_source=iContact&
25) ”NASA Gauges Plant Stress in Costa Rican Drought,” NASA/JPL News, 8 August 2019, URL: https://www.jpl.nasa.gov/news/news.php?release=2019-161
26) ”NASA's ECOSTRESS Maps European Heat Wave From Space,” NASA/JPL, 2 July 2019, URL: https://www.jpl.nasa.gov/news/news.php?feature=7445&utm_source=iContact&
27) ”Houston, we’re here to help the farmers,” ASA (American Society of Agronomy), 6 March 2019, URL: https://www.agronomy.org/science-news/houston-were-here-to-help-the-farmers
28) ”Sweating Can Be Cool,” NASA Science, 5 October 2018, URL: https://science.nasa.gov
29) ”ECOSTRESS Maps LA's Hot Spots,” NASA/JPL News, 18 September 2018, URL: https://www.jpl.nasa.gov/news/news.php?release=2018-217
30) ”NASA's 'Space Botanist' Observes California, Nevada Wildfires,” NASA/JPL News, 2 August 2018, URL: https://www.jpl.nasa.gov/news/news.php?release=2018-185
31) ”NASA's 'Space Botanist' Gathers First Data,” NASA/JPL News Release:218-172 , 23 July 2018, URL: https://www.jpl.nasa.gov/news/news.php?release=2018-172
32) ”SpaceX CRS-15 Dragon arrives at ISS with science/crew supply payloads,” NASA Spaceflight, 2 July 2018, URL: https://www.nasaspaceflight.com/2018
33) ”Visiting Vehicle Launches, Arrivals and Departures,” NASA, 2 July 2018, URL: https://www.nasa.gov/feature/visiting-vehicle-launches-arrivals-and-departures
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 (firstname.lastname@example.org).