Q&A with the US lead scientist for the mission, which tracks changes in everything from wetlands to ice sheets to infrastructure damaged by natural disasters.
The upcoming U.S.-India NISAR (NASA-ISRO Synthetic Aperture Radar) mission will observe the Earth in a different way than previous missions, providing insight into Earth’s ever-changing surface.
The NISAR mission is a unique dual-band radar satellite that measures land deformation due to earthquakes, landslides, and volcanoes, and generates data for science and disaster response. Track how much glaciers and ice sheets are advancing or retreating, and monitor the growth and loss of forests and wetlands to gain insight into the global carbon cycle.
NISAR’s impact is wide-ranging, but the mission’s winding journey, which launches in a few months, is also noteworthy. Paul Rosen, a NISAR project scientist at NASA’s Jet Propulsion Laboratory in Southern California, has been involved in the field every step of the way. He recently spoke about its mission and its characteristics.
The surface of the planet never stops changing. Small and subtle in some ways, monumental and sudden in others. In NISAR, each pixel captures an area about half the size of a tennis court, and changes in it are measured approximately weekly. Imaging nearly all of Earth’s land and ice surfaces so frequently and at scales as small as centimeters means that we can bring those pieces together into one coherent picture and learn more about the planet as a living system. help create a story.
NISAR will be the first Earth observation satellite to be equipped with two types of radar: an L-band system with a wavelength of 10 inches (25 centimeters) and an S-band system with a wavelength of 4 inches (10 centimeters).
Whether microwaves are reflected or transmitted through an object depends on its wavelength. Shorter wavelengths are more sensitive to small objects such as leaves or rough surfaces, while longer wavelengths are more reactive to large structures such as rocks or tree trunks.
Therefore, the two NISAR radar signals will respond differently to some features on the Earth’s surface. By taking advantage of what each signal is or isn’t sensitive to, researchers can study a wider range of features than using either radar alone and observe the same features at different wavelengths. You can.
The concept of spaceborne synthetic aperture radar (SAR) to study Earth processes dates back to the 1970s when NASA launched Seasat. Although the mission lasted only a few months, it produced the first images that changed the landscape of remote sensing for decades to come.
I was also drawn to JPL in 1981 as a college student. I spent two summers analyzing data from the mission. Seasat led to NASA’s Shuttle Imaging Radar Program, which led to the Shuttle Radar Topographic Survey Mission.
Our data products meet the needs of users across the mission’s science focus areas, including ecosystems, cryosphere, and solid Earth, and can be used for many applications beyond basic research, such as monitoring soil moisture and water resources. Masu.
Make your data easily accessible. Given the amount of data, NASA decided to process it and store it in the cloud, making it freely accessible.
We proposed an L-band satellite, DESDynI (Ice Deformation, Ecosystem Structure, and Dynamics), following the 2007 Decadal Survey by the National Academy of Sciences. At that time, ISRO was considering launching an S-band satellite. The two science teams proposed a dual-band mission and in 2014, NASA and ISRO agreed to partner on NISAR.
Since then, the two agencies have worked together across more than 9,000 miles (14,500 kilometers) and 13 time zones. The hardware was manufactured on different continents and then assembled in India to complete the satellite. It was literally a long journey.
The NISAR mission is an equal partnership between NASA and ISRO, and marks the first time that the two agencies are collaborating on hardware development for an Earth observation mission. JPL, managed for the government by the California Institute of Technology, is leading the U.S. component of the project and providing the mission’s L-band SAR. NASA also provides a radar reflector antenna, a deployable boom, a high-speed communications subsystem for scientific data, a GPS receiver, a solid-state recorder, and a payload data subsystem.
The Ahmedabad Space Applications Center, ISRO’s lead center for payload development, provides the mission’s S-band SAR instrument and is responsible for its calibration, data processing, and development of scientific algorithms to address the mission’s scientific objectives. . The UR Rao Satellite Center in Bangalore is leading the ISRO component of the mission and providing the spacecraft bus. The launch vehicle will be provided by ISRO’s Vikram Sarabhai Space Center, launch services will be provided through ISRO’s Satish Dhawan Space Center and satellite mission operations will be handled by ISRO Telemetry Tracking and Command Network. The National Remote Sensing Center in Hyderabad is primarily responsible for receiving S-band data, generating operational products, and distributing it.
For more information about NISAR, please see below.
https://nisar.jpl.nasa.gov
Andrew Wang / Jane J. Lee
Jet Propulsion Laboratory, Pasadena, California
626-379-6874 / 818-354-0307
andrew.wang@jpl.nasa.gov / jane.j.lee@jpl.nasa.gov
2025-001
