NISAR

NISAR is a joint mission of NASA and the Indian Space Research Organisation (ISRO). Its name abbreviates NASA-ISRO Synthetic Aperture Radar. The two agencies combined their radar technologies to build a satellite for systematic observations of Earth's changing surface. NASA contributed the L-band radar system and associated equipment; ISRO supplied the S-band radar, spacecraft and launch services. The mission launched on 30 July 2025 aboard ISRO's GSLV-F16 from Satish Dhawan Space Centre in India.

NISAR carries two synthetic aperture radar instruments: L-band, with a wavelength of about 24 centimetres, and S-band, with a wavelength of about 9.4 centimetres. Radar can collect measurements through clouds and in darkness, enabling regular observations independent of sunlight and many weather conditions. NASA describes a 12-day repeat cycle, with observations from ascending and descending passes that provide an average revisit of about six days over the planned primary mission. The distinct radar wavelengths respond differently to surface features, helping scientists study a broad range of changes.

NISAR's objectives include studying land and ice deformation, land ecosystems, and selected ocean regions. Repeated radar observations can reveal movement and deformation associated with earthquakes, volcanoes, landslides and changes in groundwater-related subsidence or uplift. They can also help measure changes in forests, wetlands and crops, as well as the dynamics of ice sheets, mountain glaciers and sea ice. These observations support scientific research and applications such as hazard assessment and ecosystem monitoring; the satellite supplies measurements rather than making decisions for emergency response or land management.

NASA and ISRO process and distribute mission data for researchers and other users. NASA states that NISAR data are openly available through its Alaska Satellite Facility archive, and ISRO also provides S-band products through its data services. The mission entered its science operations phase in early 2026 after launch and commissioning, according to NASA's mission overview. Its planned baseline science mission is three years; observations and data products may be refined through ongoing calibration and validation.