Geosynchronous Satellite Launch Vehicle
Also called: GSLV · Topic: Remote Sensing, GIS and GNSS · NCERT: Beyond NCERT
Meaning
The Geosynchronous Satellite Launch Vehicle (GSLV) is a heavy rocket built by ISRO. Its top stage is an Indian-made cryogenic stage. A cryogenic stage burns fuels kept at extremely low temperatures, liquid hydrogen and liquid oxygen, and this gives the rocket enough power to lift heavy satellites high. GSLV usually leaves a satellite in a geosynchronous transfer orbit (GTO). This is a long, oval "parking" orbit. The satellite then fires its own engine to climb to its final slot about 36,000 km up. GSLV matters because it lets India launch its own navigation and weather satellites without relying on foreign rockets.
Example
On 30 October 2026, GSLV-F18 lifted off from the Second Launch Pad at Satish Dhawan Space Centre, Sriharikota, on the Andhra Pradesh coast. It was GSLV's 20th flight, and it placed the NavIC satellite NVS-03 in GTO. Earlier flights carried INSAT-3DS (F14, February 2024), NVS-01 (F12, May 2023) and NVS-02 (F15, January 2025). GSLV-F16 also launched NISAR, the NASA-ISRO radar satellite, on 30 July 2025.
Don't confuse with
- PSLV (Polar Satellite Launch Vehicle): a lighter rocket used mainly to put earth observation satellites like IRS into low, sun-synchronous orbits. GSLV carries heavier satellites, mainly towards geosynchronous orbit.
- Geosynchronous transfer orbit vs final orbit: GSLV's job ends once the satellite is in GTO. NVS-02 reached GTO correctly, but the satellite's own valves did not open, so it never reached its slot. The rocket had not failed.