World’s most expensive satellite Nisar sends first sharp look at India as science phase begins

Nisar Begins Science Phase with First Sharp Look at India (Image: ISRO)

India’s newest radar satellite has started work with a scene both familiar and fresh. Its first detailed view of the country marks a moment many scientists had waited for.

Nisar’s S-Band radar captured the Godavari River Delta with striking detail, showing mangroves, fields, arecanut crops and aquaculture ponds. ISRO released the high-resolution image as the mission completed 100 days in orbit. The satellite lifted off on July 30, 2025, aboard ISRO’s GSLV-F16 from Sriharikota, starting a long sequence that prepared it for operations.

Mangroves and varied land use across the Godavari Delta, Andhra Pradesh (Image: ISRO)

The spacecraft carries a 12-metre reflector, NASA’s largest in Earth orbit. It sits on a 9-metre boom that unfolded slowly from August 9 to 15. Teams at ISRO’s ISTRAC in Bengaluru and NASA’s JPL coordinated the release of its wrist, shoulder, elbow and root joints. Checks confirmed both S-band and L-band radars worked as designed, allowing the mission to proceed.

The satellite began collecting data on August 19, scanning India and several global calibration sites. Corner reflectors near Ahmedabad helped refine pointing checks, while passes over the Amazon rainforest confirmed image consistency. These tests produced data suited for farming studies, forestry work, hydrology, geoscience mapping and Himalayan ice tracking. Analysts noted its strength in scanning deltas at night or through cloud cover.

The satellite circles at 747 km in a sun-synchronous path, covering land and ice every 12 days. Its dual-frequency system can detect tiny surface shifts, allowing earlier warnings for disasters, ecosystem changes and climate pressures.

Nisar’s progress highlights a major India-US partnership, supported by a $1.5 billion mission plan. The satellite’s regular mapping promises steady environmental insight at a time when precise data is needed worldwide. Its start of science operations shows the mission is ready for a long period of detailed observation.