NASA is setting launch coverage for NISAR — the NASA-ISRO Synthetic Aperture Radar satellite — a joint mission between the US and Indian space agencies that will provide a three-dimensional view of Earth's surface in unprecedented detail. It is one of the most significant collaborations between NASA and the Indian Space Research Organisation to date. NISAR's core capability is synthetic aperture radar (SAR), which bounces microwave signals off the Earth's surface to measure changes in land elevation, ground deformation, and ice sheet movement with millimetre-scale precision. Unlike optical satellites that take pictures, SAR works through clouds, at night, and in all weather conditions — it measures the physical shape of the planet, not just what it looks like. The "three-dimensional view" in the mission description refers to this ability to detect vertical changes in the Earth's surface over time. The practical applications are immediate and concrete. NISAR will track ground subsidence in cities built on sinking land, measure ice sheet loss in Greenland and Antarctica with new precision, monitor fault lines for earthquake hazard assessment, and observe deforestation and agricultural change. Every 12 days, the satellite will map nearly the entire planet, building a continuously updated 3D record of how Earth's surface is changing. The NASA-ISRO partnership splits the engineering. NASA's Jet Propulsion Laboratory built the L-band SAR payload and the radar reflector antenna. ISRO built the S-band SAR payload, the spacecraft bus, and is providing the launch vehicle. This division of labour reflects both agencies' strengths — JPL's radar heritage and ISRO's cost-effective spacecraft manufacturing and launch capability. The collaboration is notable in the broader context of US-India space relations, which have deepened significantly in recent years. India's Chandrayaan-3 lunar landing in 2023 made it the fourth country to soft-land on the Moon. The Artemis Accords, which India signed in 2023, formalised a framework for cooperation in space exploration. NISAR predates these developments — it has been in development for over a decade — but its launch arrives at a moment when the US-India space relationship is carrying more strategic weight than at any previous point.
