What is NISAR? Tests underway ahead of SUV-sized NASA-ISRO observatory’s 2024 launch

NASA officials revealed that the NASA-ISRO Synthetic Aperture Radar (NISAR) will be launched from the Satish Dhawan Space Centre at Sriharikota in the beginning of next year after conducting a few more tests, officials said.

NISAR (pronounced as ‘naisar’), which will be launched aboard ISRO’s GSLV Mark II, is a low-earth orbit (LEO) observatory jointly developed by NASA and ISRO.

Following a 90-day satellite commissioning period, the mission will survey out planet every 12 days. During its three-year duration, NISAR will provide spatially and temporally consistent data for understanding changes in the ecosystems, ice mass, vegetation biomass, sea level rise, ground water and natural hazards including earthquakes, tsunamis, volcanoes and landslides.

“ISRO is projecting the first quarter of next year. So, I mean, that’s ready,” NASA NISAR Project Manager Phil Barela told media in Bengaluru on Wednesday.

He added that a vibration test is underway while battery and simulation tests have to be done to make sure that the system works fine. “…we’ll be doing performance testing on the radars and various spacecraft electronics. So, a lot of testing remains but the big environments test, the only one remaining now, is vibration,” Barela said.

ISRO will supply the S-Band SAR payload while NASA will provide the L-Band SAR payload system. Both these SAR (Synthetic Aperture Radar) systems will make use of a 12m wide deployable mesh reflector, according to ISRO.

ISRO will be responsible for SSAR data handling system, High rate downlink system, spacecraft bus systems, the GSLV launch system and Mission Operations Related Services. On the other hand, NASA will also provide engineering payloads for the mission, including a Payload Data Subsystem, High-rate Science Downlink System, GPS receivers and a Solid State Recorder.