GISAT-1A (EOS-05): ISRO Geo-Imaging Satellite on GSLV-F17
Why in the news
ISRO was preparing a fresh launch of an Earth-watching satellite parked high above India, a second try after the earlier mission of the series was lost in 2021.
Key facts
- Satellite: GISAT-1A (EOS-05), agile geo-imaging, geostationary orbit (about 36,000 km).
- Rocket: GSLV-F17 (GSLV Mk-II) with the CE-7.5 cryogenic upper stage and a 4-metre Ogive fairing.
- Predecessor: GISAT-1 (EOS-03), lost on 12 August 2021 on GSLV-F10 after the cryogenic stage did not ignite.
| Aspect | Geostationary imager (GISAT-1A) | Low Earth orbit satellites (Cartosat, Resourcesat, RISAT) |
|---|---|---|
| Altitude | About 36,000 km | 500-900 km |
| Coverage | Appears fixed over one point; images same region repeatedly | Circles the planet; revisits a place every few days |
| Trade-off | Coarser ground resolution from far away | Higher resolution |
Purpose
- Near real-time, frequent imaging of the subcontinent and surrounding seas.
- Disaster monitoring: cyclones, floods, forest fires, cloudbursts.
- Agriculture and forestry: crop, drought and vegetation watch.
- Security: constant surveillance of borders and the Indian Ocean region.
About GSLV Mk-II
A three-stage medium-lift rocket: solid first stage with liquid strap-ons, liquid second stage and the indigenous cryogenic upper stage. It carries about 2.2 tonnes to geosynchronous transfer orbit.
Exam angle
- GISAT-1A = EOS-05; EOS series is ISRO’s renamed set of Earth observation satellites.
- Launcher: GSLV-F17; failed earlier try: GSLV-F10, 12 August 2021.
- GISAT complements, and does not replace, high-resolution Cartosat-class satellites.