NISAR Satellite: NASA-ISRO Radar Mission Goes Operational
Why in the news
ISRO Chairman V. Narayanan said NISAR would be formally declared operational on 7 November 2025.
Key facts
- Full name: NASA-ISRO Synthetic Aperture Radar; launched from Satish Dhawan Space Centre (GSLV-F16).
- Called the costliest Earth observation satellite ever built.
- Scans most land and ice twice in 12 days.
| Feature | Benefit |
|---|---|
| Dual-frequency SAR | L-band plus S-band in one satellite |
| 12-metre mesh antenna | Precise imaging |
| SweepSAR | 242 km swath, 12-day revisit |
| Resolution | Changes below 1 cm |
| Coverage | Day-night, all-weather |
Objectives and ISRO’s share
- Track land deformation, glaciers, ecosystems, soil moisture and coasts; aid disaster response and climate studies.
- ISRO built the S-band radar and a modified I-3K bus, and runs ground operations.
Exam angle
- L-band: NASA; S-band: ISRO.
- Revisit cycle: 12 days.