Members Can Post Anonymously On This Site
Air Force releases cardio and strength fitness assessment alternatives, new online capabilities
-
Similar Topics
-
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
2025-006
Share
Details
Last Updated Jan 21, 2025 Related Terms
NISAR (NASA-ISRO Synthetic Aperture Radar) Earth Earth Science Earth Science Division Jet Propulsion Laboratory Explore More
4 min read NASA Scientists, Engineers Receive Presidential Early Career Awards
Article 4 days ago 6 min read NASA International Space Apps Challenge Announces 2024 Global Winners
Article 5 days ago 3 min read NASA Scientists Find New Human-Caused Shifts in Global Water Cycle
Article 5 days ago Keep Exploring Discover More Topics From NASA
Missions
Humans in Space
Climate Change
Solar System
View the full article
-
By NASA
3 min read
Preparations for Next Moonwalk Simulations Underway (and Underwater)
AS16-116-18653 (23 April 1972) — Astronaut Charles M. Duke Jr., Apollo 16 lunar module pilot, stands at a big rock adjacent (south) to the huge “House Rock” (barely out of view at right edge). Note shadow at extreme right center where the two moon-exploring crew members of the mission sampled what they referred to as the “east-by-west split of House Rock” or the open space between this rock and “House Rock”. At their post-mission press conference, the crewmen expressed the opinion that this rock was once a part of “House Rock” which had broken away. The two sampled the big boulder seen here also. Duke has a sample bag in his hand, and a lunar surface rake leans against the large boulder. Astronaut John W. Young, commander, exposed this view with a color magazine in his 70mm Hasselblad camera. While astronauts Young and Duke descended in the Apollo 16 Lunar Module (LM) “Orion” to explore the Descartes highlands landing site on the moon, astronaut Thomas K. Mattingly II, command module pilot, remained with the Command and Service Modules (CSM) “Casper” in lunar orbit.NASA The goals of the working group were to:
Endorse or recommend changes to H2S SMAC levels that had been proposed by the JSC Toxicology Laboratory Review a draft H2S SMAC manuscript prepared by the JSC Toxicology Laboratory Provide any additional insight and consideration regarding H2S toxicity that should be considered for spaceflight programs Background
The NASA Spaceflight Human-System Standard (NASA-STD-3001) establishes that vehicle systems shall limit atmospheric contamination below established limits [V2 6050] Atmosphere Contamination Limit. The JSC Toxicology Laboratory maintains the JSC 20584 Spacecraft Maximum Allowable Concentrations for Airborne Contaminants document, which contains a table of SMAC values for a variety of chemicals including carbon monoxide, ammonia, heavy metals, and a wide range of volatile organic compounds. SMACs are documented for 1-hr, 24-hr, 7-day, 30-day, 180-day, and 1000-day time spans for each chemical, and express the maximum concentration to which spaceflight crew can be exposed for that duration.
Read More The organ system that is affected as well as the effect (symptoms) are also documented for each SMAC. For more information on SMACs, see this article Exposure Guidelines (SMACs and SWEGs) – NASA and the OCHMO Spaceflight Toxicology technical brief technical brief.
Read More A SMAC value for hydrogen sulfide has not previously been established since it has not been of concern in spacecraft. However, with Artemis missions returning to the moon there is a possibility that H2S could be released within spacecraft during lunar sample return, given that this compound may be a component of lunar polar ice. H2S has an intense smell of rotten eggs and therefore has a distracting psychological element. Physiologically it has been shown to be an irritant at low concentrations and in high concentrations can potentially lead to neurological effects and unconsciousness.
Hydrogen sulfide SMAC values will define safe limits for spaceflight crews on future missions and could drive new requirements for monitoring and mitigation of this chemical during spaceflight.
Read More Conclusions
Key points of the review were:
The proposed 1-hour, 24-hour, 7-day, 30-day, and 180-day SMAC values were deemed appropriate and were endorsed by each of the panel members. The proposed 1000-day SMAC value is so low that the panel’s opinion is that this SMAC may not be attainable due to human-generated sources, and that these concentrations do not represent a true toxicological risk. The recommendation is to eliminate the 1000-day SMAC, or to call it a guideline. The general SMAC calculation approach and inclusion of safety factors is logical, although some additional rationale would be justified. Interactive and additive effects with other substances are considered negligible, particularly at these low concentrations. Microgravity-induced physiological changes are unlikely to exacerbate hydrogen sulfide exposure at these low concentrations. Recommendations were made with the understanding that these SMACs apply to pre-screened, healthy astronauts. For private spaceflight participants who may not be as well screened, the panel recommended individual physician attention and a review of all SMACs (including hydrogen sulfide), to identify sensitivities in certain populations (existing disease states, etc.). Passive dosimetry technology is available and should be considered for long-term monitoring at these low concentrations. Following consideration of the panel’s recommendation, the NASA/TM-20240000101 Exposure Limits for Hydrogen Sulfide in Spaceflight was revised and released by the JSC toxicology group in January of 2024 and is available below.
Read More Astronaut Woody Hoburg replaces life support system components inside the International Space Station’s Destiny laboratory module.NASA About the Author
Kim Lowe
Human Systems Standards Integrator
Share
Details
Last Updated Jan 17, 2025 Related Terms
Office of the Chief Health and Medical Officer (OCHMO) Human Health and Performance Humans in Space The Human Body in Space Keep Exploring Discover More Topics From OCHMO Standards
Human Spaceflight Standards
The Human Spaceflight & Aviation Standards Team continually works with programs to provide the best standards and implementation documentation to…
Aerospace Medical Certification Standard
This NASA Technical Standard provides medical requirements and clinical procedures designed to ensure crew health and safety and occupational longevity…
Aviation Medical Certification Standards
This document provides the standards and administrative procedures for the aviation medical certification of NASA aviation flight personnel. It ensures…
Technical Briefs
Technical Briefs are available for standards that offer technical data, background, and application notes for vehicle developers and medical professionals.…
View the full article
-
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/
View the full article
-
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
Share
Details
Last Updated Jan 16, 2025 EditorKate D. RamsayerContactKate D. Ramsayerkate.d.ramsayer@nasa.gov Related Terms
Earth Global Precipitation Measurement (GPM) Goddard Space Flight Center Moderate Resolution Imaging Spectroradiometer (MODIS) Water & Energy Cycle Explore More
4 min read NASA’s Global Precipitation Measurement Mission: 10 years, 10 stories
From peering into hurricanes to tracking El Niño-related floods and droughts to aiding in disaster…
Article 11 months ago 4 min read NASA Satellites Find Snow Didn’t Offset Southwest US Groundwater Loss
Article 7 months ago 4 min read NASA Satellites Reveal Abrupt Drop in Global Freshwater Levels
Earth’s total amount of freshwater dropped abruptly starting in May 2014 and has remained low…
Article 2 months ago View the full article
-
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.
View the full article
-
-
Check out these Videos
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.