NVS-03 Navigation Satellite Reaches Geosynchronous Orbit: What It Means for NavIC
The Indian Space Research Organisation (ISRO) said its navigation satellite NVS-03 has reached its planned geosynchronous orbit, and the satellite is in good health.
ISRO completed four orbit manoeuvres (planned engine firings that raise the satellite's path step by step) using the satellite's Liquid Apogee Motor (LAM). The total engine burn time was 6,164 seconds.
The satellite now orbits at an inclination of 29.98°, which means its path is tilted about 30 degrees to the Equator. It is meant for the 111.75° East orbital slot.
NVS-03 was launched on 30 October 2026 from Satish Dhawan Space Centre, Sriharikota, on GSLV-F18, the 20th flight of the GSLV rocket. The rocket first placed it in an oval transfer orbit of about 170 km x 38,080 km. The first LAM burn (2,174.8 seconds) was done on 31 October.
NVS-03 weighs about 2,250 kg. It is a second-generation satellite for NavIC, India's own satellite navigation system.
Its predecessor, NVS-02 (launched January 2025), could not reach its working orbit because of a pyro valve problem. For NVS-03, ISRO kept the pyro valves open before launch and used solenoid valves to control fuel flow. ISRO plans to launch NVS-04, NVS-05 and a replacement for NVS-02 next.
NavIC (IRNSS): India's Regional Navigation Satellite System
NavIC is India's own satellite navigation system, like the American GPS but covering India and the nearby region. It tells a user their exact position and the exact time using signals from a group of Indian satellites. Its official name is the Indian Regional Navigation Satellite System (IRNSS); it was named NavIC (Navigation with Indian Constellation) in 2016. It covers India and about 1,500 km beyond its borders.
Several older IRNSS satellites have lost their atomic clocks, and NVS-02 failed to reach its orbit. NVS-03 reaching its slot helps rebuild the constellation towards the seven satellites NavIC needs for full service.
Orbit Classification: LEO, GTO, Sub-GTO and Geostationary Orbit
An orbit is the curved path a satellite follows as it keeps falling around the Earth without hitting it. Satellites are grouped by how high they fly and the shape of their path. A satellite at about 35,786 km above the Equator takes exactly one sidereal day (about 23 hours 56 minutes) to go around the Earth, the same time the Earth takes to spin once.
NVS-03 is a geosynchronous satellite, not a geostationary one, because its orbit is tilted by about 30 degrees. This tilt lets the inclined NavIC satellites move north and south over India, which improves the geometry of the signals and the accuracy of position fixes.
GSLV (Geosynchronous Satellite Launch Vehicle) Programme
The Geosynchronous Satellite Launch Vehicle (GSLV) is an Indian rocket built by ISRO to carry heavier satellites, about 2 to 2.5 tonnes, into high orbits. Its main job is to place communication, weather and navigation satellites into a Geosynchronous Transfer Orbit. It has three stages, and its top stage uses a cryogenic engine (an engine that burns liquid hydrogen with liquid oxygen, kept at very low temperatures).
GSLV delivered NVS-03 into a very precise transfer orbit, and the satellite's own LAM engine then did the rest of the climb. The mission shows how rocket and satellite share the job of reaching a high orbit.
- Satellite: NVS-03, about 2,250 kg, second-generation NavIC satellite
- Launch: 30 October 2026, GSLV-F18 (20th GSLV flight), Sriharikota
- Initial transfer orbit: about 170.3 km x 38,080 km
- Orbit raising: 4 manoeuvres, total LAM burn 6,164 seconds; first burn 2,174.8 seconds on 31 October
- Final orbit: geosynchronous, inclination 29.98°; target slot 111.75°E
- NavIC: 7 satellites planned (3 GEO + 4 inclined GSO); coverage India + about 1,500 km
- NVS series signals: L1, L5 and S bands; Indian rubidium atomic clock on board
- NVS-02 (January 2025, GSLV-F15) failed to reach orbit because of a pyro valve fault
- Next: NVS-04, NVS-05 and an NVS-02 replacement