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By NASA
NASA’s Jet Propulsion Laboratory used radar data taken by ESA’s Sentinel-1A satellite before and after the 2015 eruption of the Calbuco volcano in Chile to create this inter-ferogram showing land deformation. The color bands west of the volcano indicate land sinking. NISAR will produce similar images.ESA/NASA/JPL-Caltech A SAR image — like ones NISAR will produce — shows land cover on Mount Okmok on Alaska’s Umnak Island . Created with data taken in August 2011 by NASA’s UAVSAR instrument, it is an example of polarimetry, which measures return waves’ orientation relative to that of transmitted signals.NASA/JPL-Caltech Data from NASA’s Magellan spacecraft, which launched in 1989, was used to create this image of Crater Isabella, a 108-mile-wide (175-kilometer-wide) impact crater on Venus’ surface. NISAR will use the same basic SAR principles to measure properties and characteristics of Earth’s solid surfaces.NASA/JPL-Caltech Set to launch within a few months, NISAR will use a technique called synthetic aperture radar to produce incredibly detailed maps of surface change on our planet.
When NASA and the Indian Space Research Organization’s (ISRO) new Earth satellite NISAR (NASA-ISRO Synthetic Aperture Radar) launches in coming months, it will capture images of Earth’s surface so detailed they will show how much small plots of land and ice are moving, down to fractions of an inch. Imaging nearly all of Earth’s solid surfaces twice every 12 days, it will see the flex of Earth’s crust before and after natural disasters such as earthquakes; it will monitor the motion of glaciers and ice sheets; and it will track ecosystem changes, including forest growth and deforestation.
The mission’s extraordinary capabilities come from the technique noted in its name: synthetic aperture radar, or SAR. Pioneered by NASA for use in space, SAR combines multiple measurements, taken as a radar flies overhead, to sharpen the scene below. It works like conventional radar, which uses microwaves to detect distant surfaces and objects, but steps up the data processing to reveal properties and characteristics at high resolution.
To get such detail without SAR, radar satellites would need antennas too enormous to launch, much less operate. At 39 feet (12 meters) wide when deployed, NISAR’s radar antenna reflector is as wide as a city bus is long. Yet it would have to be 12 miles (19 kilometers) in diameter for the mission’s L-band instrument, using traditional radar techniques, to image pixels of Earth down to 30 feet (10 meters) across.
Synthetic aperture radar “allows us to refine things very accurately,” said Charles Elachi, who led NASA spaceborne SAR missions before serving as director of NASA’s Jet Propulsion Laboratory in Southern California from 2001 to 2016. “The NISAR mission will open a whole new realm to learn about our planet as a dynamic system.”
Data from NASA’s Magellan spacecraft, which launched in 1989, was used to create this image of Crater Isabella, a 108-mile-wide (175-kilometer-wide) impact crater on Venus’ surface. NISAR will use the same basic SAR principles to measure properties and characteristics of Earth’s solid surfaces.NASA/JPL-Caltech How SAR Works
Elachi arrived at JPL in 1971 after graduating from Caltech, joining a group of engineers developing a radar to study Venus’ surface. Then, as now, radar’s allure was simple: It could collect measurements day and night and see through clouds. The team’s work led to the Magellan mission to Venus in 1989 and several NASA space shuttle radar missions.
An orbiting radar operates on the same principles as one tracking planes at an airport. The spaceborne antenna emits microwave pulses toward Earth. When the pulses hit something — a volcanic cone, for example — they scatter. The antenna receives those signals that echo back to the instrument, which measures their strength, change in frequency, how long they took to return, and if they bounced off of multiple surfaces, such as buildings.
This information can help detect the presence of an object or surface, its distance away, and its speed, but the resolution is too low to generate a clear picture. First conceived at Goodyear Aircraft Corp. in 1952, SAR addresses that issue.
“It’s a technique to create high-resolution images from a low-resolution system,” said Paul Rosen, NISAR’s project scientist at JPL.
As the radar travels, its antenna continuously transmits microwaves and receives echoes from the surface. Because the instrument is moving relative to Earth, there are slight changes in frequency in the return signals. Called the Doppler shift, it’s the same effect that causes a siren’s pitch to rise as a fire engine approaches then fall as it departs.
Computer processing of those signals is like a camera lens redirecting and focusing light to produce a sharp photograph. With SAR, the spacecraft’s path forms the “lens,” and the processing adjusts for the Doppler shifts, allowing the echoes to be aggregated into a single, focused image.
Using SAR
One type of SAR-based visualization is an interferogram, a composite of two images taken at separate times that reveals the differences by measuring the change in the delay of echoes. Though they may look like modern art to the untrained eye, the multicolor concentric bands of interferograms show how far land surfaces have moved: The closer the bands, the greater the motion. Seismologists use these visualizations to measure land deformation from earthquakes.
Another type of SAR analysis, called polarimetry, measures the vertical or horizontal orientation of return waves relative to that of transmitted signals. Waves bouncing off linear structures like buildings tend to return in the same orientation, while those bouncing off irregular features, like tree canopies, return in another orientation. By mapping the differences and the strength of the return signals, researchers can identify an area’s land cover, which is useful for studying deforestation and flooding.
Such analyses are examples of ways NISAR will help researchers better understand processes that affect billions of lives.
“This mission packs in a wide range of science toward a common goal of studying our changing planet and the impacts of natural hazards,” said Deepak Putrevu, co-lead of the ISRO science team at the Space Applications Centre in Ahmedabad, India.
Learn more about NISAR at:
https://nisar.jpl.nasa.gov
News Media Contacts
Andrew Wang / Jane J. Lee
Jet Propulsion Laboratory, Pasadena, Calif.
626-379-6874 / 818-354-0307
andrew.wang@jpl.nasa.gov / jane.j.lee@jpl.nasa.gov
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Last Updated Jan 21, 2025 Related Terms
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By NASA
Freelancer NASA’s Sustainable Business Model Challenge is looking for entrepreneurs, startups, and researchers to leverage the agency’s publicly available Earth system science data to develop commercial solutions for climate challenges.
This opportunity, with a submission deadline of June 13, bridges the gap between vast climate data and actionable solutions by inviting solvers to transform data into sustainable business models that support climate resilience and decision-making.
“Creative, outcome-driven entrepreneurs are the lifeblood of our country’s economy, and we’re excited to see the sustainable climate solutions they’re able to come up with when working closely with NASA’s vast resources and data,” said Jason L. Kessler, program executive for the NASA Small Business Innovation Research / Small Business Technology Transfer (SBIR/STTR) program, which is sponsoring the challenge.
Through the Sustainable Business Model Challenge, NASA aims to foster a new set of sustainable enterprises capable of turning climate insights into tangible market-ready services, ultimately contributing to a more resilient future for vulnerable communities, businesses, and ecosystems. NASA is committed to broadening participation in its solicitations and fostering technology advancements.
By engaging new entrepreneurs, the challenge serves as a pathway to NASA’s SBIR/STTR program, helping scale solutions to advance the global response to climate change and encourage a more sustainable future. From its vantage point in space, NASA holds a wealth of data that can inform new approaches to climate adaptation and mitigation.
Participants will submit a 10-page business concept paper that includes details on how they will incorporate NASA climate or Earth system data to deliver a product or service. Up to ten winning teams will receive $10,000 each, along with admission to a 10-week capability development training designed to strengthen any future proposals for potential NASA funding.
NASA’s SBIR/STTR program, managed by the agency’s Space Technology Mission Directorate, is part of America’s Seed Fund, the nation’s largest source of early-stage funding for innovative technologies. Through this program, entrepreneurs, startups, and small businesses with less than 500 employees can receive funding and non-monetary support to build, mature, and commercialize their technologies, advancing NASA missions and advancing the nations aerospace economy.
Ensemble is hosting the challenge on behalf of NASA. The NASA Tournament Lab, part of the Prizes, Challenges, and Crowdsourcing program in the Space Technology Mission Directorate, manages the challenge. The program supports global public competitions and crowdsourcing as tools to advance NASA research and development and other mission needs.
The deadline to participate in NASA’s Sustainable Business Model Challenge is June 13, 2025.
For more information about the challenge, visit: https://nasabusinesschallenge.org/
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By NASA
3 Min Read NASA Scientists Find New Human-Caused Shifts in Global Water Cycle
Cracked mud and salt on the valley floor in Death Valley National Park in California can become a reflective pool after rains. (File photo) Credits: NPS/Kurt Moses In a recently published paper, NASA scientists use nearly 20 years of observations to show that the global water cycle is shifting in unprecedented ways. The majority of those shifts are driven by activities such as agriculture and could have impacts on ecosystems and water management, especially in certain regions.
“We established with data assimilation that human intervention in the global water cycle is more significant than we thought,” said Sujay Kumar, a research scientist at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, and a co-author of the paper published in the Proceedings of the National Academy of Sciences.
The shifts have implications for people all over the world. Water management practices, such as designing infrastructure for floods or developing drought indicators for early warning systems, are often based on assumptions that the water cycle fluctuates only within a certain range, said Wanshu Nie, a research scientist at NASA Goddard and lead author of the paper.
“This may no longer hold true for some regions,” Nie said. “We hope that this research will serve as a guide map for improving how we assess water resources variability and plan for sustainable resource management, especially in areas where these changes are most significant.”
One example of the human impacts on the water cycle is in North China, which is experiencing an ongoing drought. But vegetation in many areas continues to thrive, partially because producers continue to irrigate their land by pumping more water from groundwater storage, Kumar said. Such interrelated human interventions often lead to complex effects on other water cycle variables, such as evapotranspiration and runoff.
Nie and her colleagues focused on three different kinds of shifts or changes in the cycle: first, a trend, such as a decrease in water in a groundwater reservoir; second, a shift in seasonality, like the typical growing season starting earlier in the year, or an earlier snowmelt; and third a change in extreme events, like “100-year floods” happening more frequently.
The scientists gathered remote sensing data from 2003 to 2020 from several different NASA satellite sources: the Global Precipitation Measurement mission satellite for precipitation data, a soil moisture dataset from the European Space Agency’s Climate Change Initiative, and the Gravity Recovery and Climate Experiment satellites for terrestrial water storage data. They also used products from the Moderate Resolution Imaging Spectroradiometer satellite instrument to provide information on vegetation health.
“This paper combines several years of our team’s effort in developing capabilities on satellite data analysis, allowing us to precisely simulate continental water fluxes and storages across the planet,” said Augusto Getirana, a research scientist at NASA Goddard and a co-author of the paper.
The study results suggest that Earth system models used to simulate the future global water cycle should evolve to integrate the ongoing effects of human activities. With more data and improved models, producers and water resource managers could understand and effectively plan for what the “new normal” of their local water situation looks like, Nie said.
By Erica McNamee
NASA’s Goddard Space Flight Center, Greenbelt, Maryland
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Last Updated Jan 16, 2025 EditorKate D. RamsayerContactKate D. Ramsayerkate.d.ramsayer@nasa.gov Related Terms
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By Space Force
Space Launch Delta 45 supported the maiden flight for Blue Origin’s New Glenn from Space Launch Complex 36 at Cape Canaveral Space Force Station.
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By NASA
Pandora, NASA’s newest exoplanet mission, is one step closer to launch with the completion of the spacecraft bus, which provides the structure, power, and other systems that will enable the mission to carry out its work.
Watch to learn more about NASA’s Pandora mission, which will revolutionize the study of exoplanet atmospheres.
NASA’s Goddard Space Flight Center “This is a huge milestone for us and keeps us on track for a launch in the fall,” said Elisa Quintana, Pandora’s principal investigator at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “The bus holds our instruments and handles navigation, data acquisition, and communication with Earth — it’s the brains of the spacecraft.”
Pandora, a small satellite, will provide in-depth study of at least 20 known planets orbiting distant stars in order to determine the composition of their atmospheres — especially the presence of hazes, clouds, and water. This data will establish a firm foundation for interpreting measurements by NASA’s James Webb Space Telescope and future missions that will search for habitable worlds.
Pandora’s spacecraft bus was photographed Jan. 10 within a thermal-vacuum testing chamber at Blue Canyon Technologies in Lafayette, Colorado. The bus provides the structure, power, and other systems that will enable the mission to help astronomers better separate stellar features from the spectra of transiting planets. NASA/Weston Maughan, BCT “We see the presence of water as a critical aspect of habitability because water is essential to life as we know it,” said Goddard’s Ben Hord, a NASA Postdoctoral Program Fellow who discussed the mission at the 245th meeting of the American Astronomical Society in National Harbor, Maryland. “The problem with confirming its presence in exoplanet atmospheres is that variations in light from the host star can mask or mimic the signal of water. Separating these sources is where Pandora will shine.”
Funded by NASA’s Astrophysics Pioneers program for small, ambitious missions, Pandora is a joint effort between Lawrence Livermore National Laboratory in California and NASA Goddard.
“Pandora’s near-infrared detector is actually a spare developed for the Webb telescope, which right now is the observatory most sensitive to exoplanet atmospheres,” Hord added. “In turn, our observations will improve Webb’s ability to separate the star’s signals from those of the planet’s atmosphere, enabling Webb to make more precise atmospheric measurements.”
Astronomers can sample an exoplanet’s atmosphere when it passes in front of its star as seen from our perspective, an event called a transit. Part of the star’s light skims the atmosphere before making its way to us. This interaction allows the light to interact with atmospheric substances, and their chemical fingerprints — dips in brightness at characteristic wavelengths — become imprinted in the light.
But our telescopes see light from the entire star as well, not just what’s grazing the planet. Stellar surfaces aren’t uniform. They sport hotter, unusually bright regions called faculae and cooler, darker regions similar to sunspots, both of which grow, shrink, and change position as the star rotates.
An artist’s concept of the Pandora mission, seen here without the thermal blanketing that will protect the spacecraft, observing a star and its transiting exoplanet. NASA’s Goddard Space Flight Center/Conceptual Image Lab Using a novel all-aluminum, 45-centimeter-wide (17 inches) telescope, jointly developed by Livermore and Corning Specialty Materials in Keene, New Hampshire, Pandora’s detectors will capture each star’s visible brightness and near-infrared spectrum at the same time, while also obtaining the transiting planet’s near-infrared spectrum. This combined data will enable the science team to determine the properties of stellar surfaces and cleanly separate star and planetary signals.
The observing strategy takes advantage of the mission’s ability to continuously observe its targets for extended periods, something flagship missions like Webb, which are in high demand, cannot regularly do.
Over the course of its year-long prime mission, Pandora will observe at least 20 exoplanets 10 times, with each stare lasting a total of 24 hours. Each observation will include a transit, which is when the mission will capture the planet’s spectrum.
Pandora is led by NASA’s Goddard Space Flight Center. Lawrence Livermore National Laboratory provides the mission’s project management and engineering. Pandora’s telescope was manufactured by Corning and developed collaboratively with Livermore, which also developed the imaging detector assemblies, the mission’s control electronics, and all supporting thermal and mechanical subsystems. The infrared sensor was provided by NASA Goddard. Blue Canyon Technologies provided the bus and is performing spacecraft assembly, integration, and environmental testing. NASA’s Ames Research Center in California’s Silicon Valley will perform the mission’s data processing. Pandora’s mission operations center is located at the University of Arizona, and a host of additional universities support the science team.
Download high-resolution video and images from NASA’s Scientific Visualization Studio
By Francis Reddy
NASA’s Goddard Space Flight Center, Greenbelt, Md.
Media Contact:
Claire Andreoli
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claire.andreoli@nasa.gov
NASA’s Goddard Space Flight Center, Greenbelt, Md.
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Last Updated Jan 16, 2025 Related Terms
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