NISAR Mission Countdown Begins: India and US Set to Launch Groundbreaking Earth Observation Satellite
The countdown is on for the imminent launch of the NASA-ISRO Synthetic Aperture Radar (NISAR) mission on July 30, 2025, at 17:40 IST from Satish Dhawan Space Centre in Sriharikota, Andhra Pradesh. A milestone for Indo-US space cooperation, NISAR is the world’s first dual-frequency radar imaging satellite, representing a significant collaboration between the Indian Space Research Organisation (ISRO) and the National Aeronautics and Space Administration (NASA). With growing interest, NISAR will be a game changer for Earth observation, producing vital measurements for an exceptional range of applications, including climate change, natural disasters, and sustainable development.
At 2392 kg, NISAR is an innovative Earth observation satellite with both L-band and S-band Synthetic Aperture Radar (SAR) systems which incorporate the 12-meter unfurlable mesh antenna from NASA and a modified version of ISRO’s I3K satellite bus. Using SweepSAR technology, NISAR can generate high-resolution images across a wide 242-kilometer swath. When operating in its nominal repeat mode, NISAR will be able to scan almost all of Earth’s land and ice surfaces every 12 days.
NISAR’s purpose is to observe the disturbance of complex natural processes such as disturbances in ecosystem dynamics, changes in ice-sheets, and the effects of natural hazards such as earthquakes, tsunamis, and landslides. The NISAR mission will provide high quality data that will be consistent day or night or when clouds obscure the view and this will provide global science and policy with a unique opportunity that is unprecedented.
NISAR, which is a mission costing $1.5 billion, represents ten years of collaboration between NASA and the Indian Space Research Organization (ISRO). The collaboration agreement was signed in 2014, with NASA providing the L-band synthetic aperture radar, global positioning systems, and data systems with large capacity, while ISRO provided the S-band synthetic aperture radar, the Geosynchronous Satellite Launch Vehicle (GSLV-F16), and launch services. The satellite should be completely integrated by January 2024 but must complete a sequence of rigorous tests to address the temperature of its radar reflector. The plan is to successfully deploy NISAR into a sun-synchronous polar orbit for at least a three-year mission, with the data being available without restrictions within days of the commissioning of the satellite. NASA will host the L-band data at the Alaska Satellite Facility, and ISRO will host the S-band data on the Bhoonidhi portal for researchers around the world.
NISAR, for India, closely resembles national priorities. From observing Himalayan glaciers or coastal ecosystems to better preparation for disasters or agricultural management. As Union Minister Jitendra Singh, said NISAR adds to India’s pockets of climate resilience by stating, “NISAR’s data will help the government take a proactive approach to environmental challenges.” In fact, this mission is relevant globally. It also helps nations respond to disasters and manage their resources in ever greater competition for it. There are many applications of the NISAR mission – from monitoring groundwater use to understanding seismic risk. With ISRO Chairman V Narayanan, said in an interview there has been rising technical sophistication in India and with the GSLV-F16 this is the first time this lift vehicle will be used to launch a Sun-synchronous orbit.
While the world is waiting for NISAR and its launch to take place, the mission is tied to India’s growing significance as a global player in space. There will be live coverage of the launch at 17:10 IST on July 30, and it is important to distinguish that this is not about simply launching a satellite but paving the way for far-reaching global collaboration that provide a view of our changing planet. Join us in this excitement and witness history in the process.
