Chandigarh, Aug 16: Seventeen days after its launch, the joint NASA-ISRO Synthetic Aperture Radar (NISAR) satellite has fully deployed its massive 39-foot radar antenna in orbit, marking a critical step toward its commissioning and scientific operations.
The milestone was confirmed on August 16, when NASA announced, “Giant Radar Antenna Reflector on NASA-ISRO Satellite in Full Bloom.” The agency noted that one of the most advanced radar instruments ever launched had successfully unfurled in space.
The antenna, weighing 64 kilograms and built with 123 composite struts and a gold-plated wire mesh, had been stowed like an umbrella before its gradual release. On August 9, the satellite’s boom began extending joint by joint, and by August 15, explosive bolts released the reflector assembly, initiating what NASA described as a “bloom.” Motors and cables then locked the 12-meter-wide structure into its operational position.
“Today, the satellite successfully unfurled its 39-foot-wide (12-meter-wide) antenna reflector. It’s the largest reflector NASA has ever deployed in space,” the agency’s Jet Propulsion Laboratory posted on X. The laboratory added that the achievement brings NISAR “one big step closer to beginning its mission to study Earth’s changing surfaces.”
Launched on July 30 aboard ISRO’s GSLV F-16 rocket from the Satish Dhawan Space Centre, NISAR is currently in a 747-kilometer polar orbit. The satellite weighs 2,392 kilograms and carries dual-frequency payloads: the L-band radar system developed by NASA and the S-band radar system designed by ISRO. The spacecraft also integrates a high-speed data downlink, GPS receiver, and solid-state recorder.
Karen St. Germain, director of NASA’s Earth Science Division, called the reflector deployment “a significant milestone.” She said in a statement, “From innovative technology to research and modeling to delivering science to help inform decisions, the data NISAR is poised to gather will have a major impact on how global communities and stakeholders improve infrastructure, prepare for and recover from natural disasters, and maintain food security.”
The satellite’s primary mission includes monitoring ice sheets and glaciers, measuring land deformation caused by earthquakes, volcanoes, and landslides, and studying changes in forests and wetlands with accuracy down to fractions of an inch. Officials said its data will support decision-making in disaster response, agriculture, and infrastructure planning.
Over the next two-and-a-half months, NISAR will undergo in-orbit checks and calibrations before beginning full-scale scientific operations. ISRO will oversee satellite command and operations, while NASA will manage the orbit maneuver and radar operations plans. Both agencies will provide ground station support for downloading and processing images before distribution to global users.
NISAR represents the first space mission to use dual-frequency radar to track Earth’s surface changes with unprecedented precision. Officials from both agencies noted that its findings will play a vital role in understanding the planet’s dynamic processes and preparing for challenges posed by climate change and natural disasters.
