NISAR (NASA-ISRO Synthetic Aperture Radar) satellite, the first dual-frequency Earth observation satellite jointly developed by ISRO and NASA, was successfully launched aboard GSLV-F16 from Satish Dhawan Space Centre (SDSC), Sriharikota, Andhra Pradesh.
The satellite weighing 2,392 kg injected into a Sun-synchronous, polar orbit by ISRO’s GSLV Mk-II launch vehicle.
Key Highlights
- NISAR was placed in a sun-synchronous polar orbit at an altitude of 747 km with 98.4° inclination.
- The satellite weighs 2,392 kg and is built around ISRO’s I-3K mainframe bus.
- This is the first ISRO-NASA collaboration in satellite development.
- NISAR uses dual-frequency SAR (Synthetic Aperture Radar):
- L-band developed by NASA
- S-band developed by ISRO’s SAC (Space Applications Centre)
- Mission life: 5 years
- Equipped with a 12-meter unfurlable reflector antenna mounted on a 9-meter boom.
- Observation swath: ~240 km with 5–100 m resolution using SweepSAR technology.
- NISAR will collect all-weather, day-and-night data every 12 days.
Objectives & Applications of NISAR
- Measure woody biomass & forest carbon
- Track crop area & active agriculture
- Map wetland extent
- Monitor ice sheets in Greenland, Antarctica
- Track mountain glacier changes, sea-ice dynamics
- Detect land surface deformation due to:
- Seismic activity
- Volcanism
- Landslides
- Groundwater & oil/gas reservoir changes
Spacecraft & Collaboration
| Component | Developed By |
| L-band SAR, boom & reflector | NASA (JPL) |
| S-band SAR, satellite bus | ISRO |
| Ground support | ISRO + NASA |
| Commanding & operations | ISRO |
| Radar operations planning | NASA |
- Satellite data will be freely available and shared with global user community.
Mission Phases
- Launch Phase: GSLV-F16 launch from SDSC SHAR, Sriharikota.
- Deployment Phase: 12m antenna deployed using 9m boom in orbit.
- Commissioning Phase (90 days): System checks and calibration.
- Science Operations Phase: Data acquisition, orbit maintenance, validation & joint science activities.
Key Facts
| Topic | Facts |
| GSLV Mk-II | India’s medium-lift launch vehicle; capable of launching up to ~2.5 tonnes into GTO |
| Sriharikota | Island on Andhra Pradesh coast; location of SDSC – ISRO’s primary launch site |
| SAR (Synthetic Aperture Radar) | Active remote sensing radar capable of high-resolution imaging through clouds, darkness, and rain |
| SweepSAR Technology | Advanced radar method that allows wide-area scans with high resolution |
| ISRO–NASA Partnership | NISAR marks the first collaborative satellite between the two space agencies |
| I-3K Satellite Bus | Modular satellite platform used by ISRO for communication and remote sensing satellites |
| Sun-synchronous Orbit | A polar orbit where the satellite passes over the same part of Earth at the same local solar time – useful for consistent imaging |