The images demonstrate how the L-band SAR can discern what type of land cover — low-lying vegetation, trees, and human structures — is present in each area. This capability is vital both for monitoring the gain and loss of forest and wetland ecosystems, as well as for tracking the progress of crops through growing seasons around the world.
“These initial images are just a preview of the hard-hitting science that NISAR will produce — data and insights that will enable scientists to study Earth’s changing land and ice surfaces in unprecedented detail while equipping decision-makers to respond to natural disasters and other challenges,” said Nicky Fox, associate administrator, Science Mission Directorate at NASA Headquarters in Washington. “They are also a testament to the years of hard work of hundreds of scientists and engineers from both sides of the world to build an observatory with the most advanced radar system ever launched by NASA and ISRO.”
The L-band system uses a 10-inch (25-centimeter) wavelength that enables its signal to penetrate forest canopies and measure soil moisture and motion of ice surfaces and land down to fractions of an inch, which is a key measurement in understanding how the land surface moves before, during, and after earthquakes, volcanic eruptions, and landslides.
The preliminary L-band images are an example of what the mission team will be able to produce when the science phase begins in November. The satellite was raised into its operational 464-mile (747-kilometer) orbit in mid-September.
The NISAR mission also includes an S-band radar, provided by ISRO’s Space Applications Centre, that uses a 4-inch (10-centimeter) microwave signal that is more sensitive to small vegetation, making it effective at monitoring certain types of agriculture and grassland ecosystems.
The spacecraft is the first to carry both L- and S-band radars. The satellite will monitor Earth’s land and ice surfaces twice every 12 days, collecting data using the spacecraft’s drum-shaped antenna reflector, which measures 39 feet (12 meters) wide — the largest NASA has ever sent into space.
The NISAR mission is a partnership between NASA and ISRO spanning years of technical and programmatic collaboration. The successful launch and deployment of NISAR builds on a strong heritage of cooperation between the United States and India in space.
The Space Applications Centre provided the mission’s S-band SAR. The U R Rao Satellite Centre provided the spacecraft bus. The launch vehicle was provided by Vikram Sarabhai Space Centre, and launch services were through Satish Dhawan Space Centre. Key operations, including boom and radar antenna reflector deployment, are now being executed and monitored by the ISRO Telemetry, Tracking and Command Network’s global system of ground stations.
Managed by Caltech in Pasadena, NASA JPL leads the U.S. component of the project. In addition to the L-band SAR, reflector, and boom, JPL also provided the high-rate communication subsystem for science data, a solid-state data recorder, and payload data subsystem. NASA’s Goddard Space Flight Center in Greenbelt, Maryland, manages the Near Space Network, which receives NISAR’s L-band data.
To learn more about NISAR, visit:
https://nisar.jpl.nasa.gov/