The NISAR satellite, a joint venture between NASA and ISRO, has successfully completed a 21-day test to evaluate its performance under extreme temperatures and space-like vacuum conditions. NISAR, short for NASA-ISRO Synthetic Aperture Radar, will be the first Earth-observing mission developed through collaboration between the two space agencies.
Scheduled for launch in early 2024, the satellite will scan the Earth’s land and ice surfaces twice every 12 days, capturing detailed data on movements and changes. This includes monitoring earthquakes, landslides, volcanic activity, as well as dynamic changes in forests, wetlands, and agricultural lands.
The recent thermal vacuum test took place at ISRO’s Satellite Integration and Test Establishment in Bengaluru, India. The test involved subjecting the satellite to extreme temperatures and reducing the pressure to simulate the vacuum conditions of space. The engineers also conducted “cold soak” and “hot soak” tests to assess the satellite’s ability to withstand temperature fluctuations while exposed to sunlight and darkness in orbit.
The performance of the satellite’s thermal and scientific instrument systems was evaluated during the test. NISAR’s L-band and S-band radars were analyzed under the most extreme temperature conditions they will encounter in space.
Prior to the test, engineers used ISRO’s compact antenna test facility to ensure that the radio signals from the radar systems’ antennas met the necessary requirements. With the successful completion of the thermal vacuum and antenna tests, the satellite will now undergo further preparations such as the installation of its solar panels and the deployment of its radar antenna reflector.
After these tasks are completed, the NISAR satellite will be transported to the Satish Dhawan Space Centre, where it will be mounted on ISRO’s Geosynchronous Satellite Launch Vehicle Mark II rocket for its journey into low Earth orbit.