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ISRO is preparing to launch EOS-05, also called GISAT-1A, on 4 September 2026 from the Second Launch Pad at the Satish Dhawan Space Centre, Sriharikota.
The 2,367 kg Earth observation satellite will be carried by the GSLV-F17 launch vehicle into a Sub-Geosynchronous Transfer Orbit.
EOS-05 is planned as India's first imaging satellite designed to operate from a geosynchronous orbit, about 36,000 km above the equator.
It is expected to provide near-real-time images of the Indian subcontinent every 30 minutes, with a revisit time of 5 minutes for priority targets.
GSLV-F17 stands 51.7 metres tall with a lift-off mass of 420.5 tonnes and is the 19th flight of the GSLV.
Most Earth observation satellites, including India's Cartosat and RISAT series, fly in low polar orbits a few hundred kilometres up. They deliver sharp imagery but pass over a given place only once every few days, so a flood or a troop movement can happen entirely between two passes. A geostationary orbit sits about 35,786 km above the equator with an orbital period equal to Earth's rotation, so the satellite hangs over the same longitude permanently. That trades resolution for persistence: images are coarser at that distance, but the same area can be revisited every few minutes. For flood mapping, cyclone tracking, crop stress monitoring and border surveillance, a picture every half hour is often worth more than a sharper picture every third day.
Simple Analogy: A low-orbit satellite is a photographer walking a fixed beat who passes your street every few days. A geostationary one is a camera fixed on a tall mast above your street, less detailed but always looking.
India's existing low-Earth-orbit imaging satellites, giving high resolution but multi-day revisit times, which EOS-05 complements rather than replaces.
India's other geostationary fleets, used for communication and meteorology; EOS-05 extends the geostationary approach to imaging.
The technology that separates GSLV from PSLV, developed indigenously after external supply was blocked, and central to India's ability to reach geosynchronous orbits.
Half-hourly imagery over the subcontinent is directly useful for flood, cyclone and landslide response, linking space capability to the National Disaster Management framework.
GS Paper 3 > Science and Technology > Space Technology, Indigenisation and Applications
General Awareness > Space Missions of India
General Awareness > Surveillance and Space-Based Assets
General Awareness > Current Affairs
General Awareness > Science and Technology
What specific physical quantity ensures a satellite maintains its orbit without continuous propulsion?
Answer: Orbital velocity
A circular orbit about 35,786 km above the equator with an orbital period equal to Earth's rotation, so the satellite appears fixed over one point.
An intermediate elliptical orbit lower than a standard geosynchronous transfer orbit, from which the satellite raises itself using onboard propulsion.
A rocket stage burning liquid hydrogen and liquid oxygen at very low temperatures, giving the high efficiency needed for geosynchronous missions.