Washington – The NASA-ISRO Synthetic Aperture Radar (NISAR) Earth-observing mission has successfully completed in-orbit tests and is preparing to transmit its first set of scientific data to ground stations.
Launched on July 30 aboard ISRO’s GSLV F-16 rocket from Sriharikota, the joint mission between NASA and ISRO is scheduled to begin science operations this fall, NASA announced on Friday.
The 39-foot-wide radar antenna reflector was deployed on August 15, after which engineers activated the satellite’s L-band and S-band synthetic aperture radar (SAR) systems. Together, these radars will deliver unprecedented insights into the movement of Earth’s ice and land surfaces.
NASA stated that the spacecraft and radar payload have cleared all initial checks by mission teams from both agencies, confirming normal operations. The satellite was raised to its operational orbit of 747 kilometers on August 26.
The mission expects to deliver science-quality radar images within weeks, while full-scale operations are planned to commence about 90 days after launch.
NISAR is the first satellite to carry two SAR systems. The L-band radar, transmitting at a 10-inch wavelength, can penetrate forest canopies to measure soil moisture, forest biomass, and land or ice surface motion. Meanwhile, the S-band radar, with a 4-inch wavelength, specializes in tracking smaller vegetation, agricultural patterns, grasslands, and snow moisture. Both radars work day and night, unaffected by clouds or precipitation.
The satellite will survey most of Earth’s land and ice twice every 12 days, offering near sub-inch precision. These measurements are vital for monitoring forests, frozen regions, large-scale infrastructure, and geological shifts linked to earthquakes, volcanic eruptions, and landslides.
India’s Space Applications Centre developed the S-band SAR, while the UR Rao Satellite Centre provided the spacecraft bus. Operations, including boom and antenna deployment, are managed by ISRO’s Telemetry, Tracking and Command Network with support from global ground stations.
NASA’s Jet Propulsion Laboratory (JPL) supplied the L-band SAR, antenna reflector, boom, high-rate communication system, data recorder, and payload subsystem. The L-band data is downlinked via NASA’s Near Space Network at the Goddard Space Flight Center in Maryland.
