About 19 minutes after lift-off, the GSLV-F16 rocket will inject the NISAR satellite into a 743-km sun-synchronous orbit. Photo: X/@isro
The countdown for the NISAR satellite mission started at 2.10 p.m. on Tuesday (July 29, 2025). The Geosynchronous Satellite Launch Vehicle (GSLV) with the 2,392-kg satellite is scheduled to lift off from the second launch pad of the Satish Dhawan Space Centre in Sriharikota at 5.40 p.m. on Wednesday (July 30, 2025).
About 19 minutes after lift-off, the GSLV-F16 rocket will inject the NISAR satellite into a 743-km sun-synchronous orbit. The NISAR satellite — NASA-ISRO Synthetic Aperture Radar satellite — will scan the Earth and provide all-weather, day-and-night data at 12-day intervals, and enable a wide range of applications.
It is the first joint satellite of the Indian Space Research Organisation (ISRO) and National Aeronautics and Space Administration (NASA).
Senior NASA officials said that working with the ISRO on the mission has strengthened their relationship.
The Director of Earth Science, NASA Headquarters, Karen St. Germain said, “Building a satellite on opposite sides of the world during a global pandemic was really hard, but it strengthened our relationship with ISRO. The collaboration, the cooperation, information sharing, and, frankly, joint learning between our two agencies is a foundation that we look forward to continuing to build upon.”
She added that NISAR is a model for the next generation of Earth observation capability.
“India built the spacecraft bus and the S-band radar and is providing the launch vehicle, launch services, and satellite mission operations. NASA’s Jet Propulsion Laboratory (JPL) built the L-band radar and the mission’s radar reflector and boom. NASA is also providing a high-rated communications subsystem for science data, GPS receivers, a solid-state recorder, and the payload data subsystem,” she added.
Phil Barela, NISAR project manager, JPL, said that the two space agencies learnt a lot from each other in the last decade.
“We have been at this for over a decade with our partner, ISRO, and it has been a phenomenal journey. The amount that we have learned from each other during this period has just been phenomenal,” Mr. Barela said.
He added that during the height of COVID-19 pandemic, around 65 ISRO engineers visited JPL to work on the integration and conduct tests.
“Over the last two-and-a-half years, NASA has sent out over 175 engineers to ISRO’s facilities to keep the integration and tests going and get us ready for where we stand today and ready for launch. It has been a wonderful journey. I’m anticipating a lot of very happy people, not only in the U.S., but also in India,” he added.
Published – July 29, 2025 09:42 pm IST