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.
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 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.
• 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 13: 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. 20)
Figure 14: 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) 21)
1) 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:
6) 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
8) Wes Schmitigal, "ECOSTRESS Payload," 2017 ECOSTRESS Science Team Meeting, 15 - 17 May 2017, URL: https://ecostress.jpl.nasa.gov/downloads/science_team_meetings
9) 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
12) 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, URL: https://ecostress.jpl.nasa.gov/downloads
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:
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&
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
16) 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/2016/08
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) "SpaceX CRS-15 Dragon arrives at ISS with science/crew supply payloads," NASA Spaceflight, 2 July 2018, URL: https://www.nasaspaceflight.com/2018/07
21) "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 (email@example.com).