GSLV-F17 launches EOS-05, India's first imaging satellite for geosynchronous orbit
A camera 36,000 km up sees less detail but looks every five minutes. Why does India want that?
Published 5 September 2026. Written by Pratidin from the reports linked at the end; every fact checked by a separate review before publishing. How we work
ISRO's GSLV-F17 lifted off from the Second Launch Pad of the Satish Dhawan Space Centre, Sriharikota, at 2.55 a.m. on 4 September 2026 and placed the 2,367 kg Earth observation satellite EOS-05 in a sub-geosynchronous transfer orbit. ISRO calls EOS-05 India's first imaging satellite for geosynchronous orbit. It was the 19th flight of the Geosynchronous Satellite Launch Vehicle (GSLV), a 51.7-metre, three-stage rocket weighing 420.5 tonnes at lift-off, with an indigenous cryogenic third stage. ISRO Chairman V. Narayanan said the vehicle "successfully and precisely injected" the satellite into the intended orbit. The satellite will now fire its own engine several times to climb to a geosynchronous orbit about 36,000 km above the Equator.
EOS-05 carries three imagers: a six-channel multispectral camera in the visible and near-infrared (VNIR) with 42-metre resolution, a 158-channel hyperspectral VNIR imager with 318-metre resolution, and a 256-channel hyperspectral short-wave infrared (SWIR) imager with 191-metre resolution. From its fixed vantage point it is designed to image selected areas every five minutes and the whole Indian landmass every 30 minutes, which suits fast-changing events such as floods, cyclones, forest fires and crop stress. ThePrint reported that the cryogenic stage performed better than planned: the achieved orbit was about 171 km by 31,026 km at 19.28 degrees inclination, against a target apogee of 28,934 km, which may leave the satellite more fuel and a longer life.
The launch ends an eight-month gap and is ISRO's first successful launch of 2026. The PSLV-C61 mission carrying EOS-09 failed in May 2025, and PSLV-C62 failed on 12 January 2026 after a third-stage anomaly. EOS-05 is also a second attempt at a geo-imaging capability: its predecessor GISAT-1 (EOS-03) was lost in August 2021 when GSLV-F10's cryogenic upper stage failed. The trade-off is resolution. Low-orbit satellites such as the Cartosat series see far finer detail but pass over a spot only occasionally; a geosynchronous imager sees coarser detail but can watch the same area continuously.
Prelims facts
- GSLV-F17 launched EOS-05 on 4 September 2026 from Sriharikota's Second Launch Pad; it was the 19th GSLV flight.
- EOS-05 (2,367 kg) is India's first imaging satellite for geosynchronous orbit, about 36,000 km above the Equator.
- Its multispectral camera has 42-metre resolution; it can image selected areas every 5 minutes and all of India every 30 minutes.
- It carries two hyperspectral imagers: 158 channels in VNIR and 256 channels in SWIR.
- GISAT-1 (EOS-03), the earlier attempt at a geo-imaging satellite, was lost when GSLV-F10's cryogenic stage failed in August 2021.
Quick recall
- Which rocket launched EOS-05?
- GSLV-F17, the 19th GSLV flight.
- Launch date and site of EOS-05?
- 4 September 2026, Second Launch Pad, Satish Dhawan Space Centre, Sriharikota.
- Mass of EOS-05?
- 2,367 kg.
- Best resolution of EOS-05?
- 42 metres (six-channel multispectral VNIR camera).
- How often can EOS-05 image selected areas and all of India?
- Every 5 minutes and every 30 minutes respectively.
- Channels in EOS-05's hyperspectral imagers?
- 158 (VNIR) and 256 (SWIR).
- Which satellite was lost on GSLV-F10 in August 2021?
- GISAT-1 (EOS-03), after the cryogenic upper stage failed.
- Approximate altitude of geosynchronous orbit?
- About 36,000 km (35,786 km) above the Equator.
Prelims practice question
With reference to EOS-05, launched by ISRO in September 2026, consider the following statements:
1. It was launched by a Polar Satellite Launch Vehicle.
2. It is meant to operate from a geosynchronous orbit.
3. It carries hyperspectral imagers in addition to a multispectral camera.
Which of the statements given above are correct?
- 1 and 2 only
- 2 and 3 only
- 1 and 3 only
- 1, 2 and 3
Show answer
Answer: (b) 2 and 3 only. 1 is wrong: it was launched by GSLV-F17. 2 is correct: it will be raised to geosynchronous orbit. 3 is correct: it has a six-channel multispectral VNIR camera and two hyperspectral imagers (VNIR and SWIR).
Use this in UPSC Mains: previous-year questions
Recurring theme: Indian space programme and its applications for socio-economic development
- How to use this
Cite EOS-05 as a recent achievement whose near-continuous imaging serves disaster management and agriculture, the socio-economic uses the question asks about.
- GSLV-F17 launched the 2,367 kg EOS-05 on 4 September 2026, India's first imaging satellite for geosynchronous orbit, about 36,000 km above the Equator.
- It can image selected areas every 5 minutes and all of India every 30 minutes, suiting floods, cyclones, forest fires and crop stress.
- It carries a 42-metre multispectral camera and hyperspectral imagers of 158 channels (VNIR) and 256 channels (SWIR), complementing finer-resolution low-orbit Cartosat satellites.
- How to use this
Use recent launch failures and the cryogenic stage's record to illustrate the launch vehicle reliability challenges that shape India's ambitions.
- GISAT-1 (EOS-03) was lost in August 2021 when GSLV-F10's cryogenic upper stage failed; PSLV-C61 failed in May 2025 and PSLV-C62 on 12 January 2026.
- GSLV-F17's indigenous cryogenic stage performed better than planned on 4 September 2026, reaching an apogee of about 31,026 km against a target of 28,934 km, ending an eight-month launch gap.
Mains practice question
India has placed its first imaging satellite in geosynchronous orbit. Explain how such a satellite differs from low Earth orbit imaging satellites and discuss its uses for disaster management and agriculture. (150 words)
Model answer
EOS-05, launched by GSLV-F17 on 4 September 2026, is India's first imaging satellite for geosynchronous orbit, about 36,000 km above the Equator.
How it differs from low-orbit imagers
- Revisit: a geosynchronous satellite keeps pace with Earth's rotation, so it can image selected areas every 5 minutes and all of India every 30 minutes; low-orbit satellites return to a spot only after days.
- Resolution: being far away, its best camera resolves 42 metres; low-orbit satellites like Cartosat see much finer detail.
- Spectral depth: 158-channel VNIR and 256-channel SWIR hyperspectral imagers identify materials by their spectral signature.
Uses
- Disasters: near-continuous watch on cyclones, floods and forest fires to time warnings and relief.
- Agriculture: tracking crop stress and soil moisture across seasons.
- Environment: dust, fires and water bodies.
Conclusion
EOS-05 complements, not replaces, low-orbit satellites, giving India a constant eye for fast-moving events.
The basics
Why this matters
A satellite's orbit decides what it can see and how often. EOS-05 is the first Indian imaging satellite built to watch the country from geosynchronous orbit. To see why that matters, you need three ideas: orbits, resolution and the rocket that gets the satellite there.
- Flies a few hundred km up
- Very fine detail, down to about a metre or better
- Passes over the same spot only occasionally
- Needs many satellites for frequent coverage
- Sits about 36,000 km above the Equator
- Coarser detail: 42 m at best
- Selected areas every 5 minutes, all of India every 30 minutes
- One satellite gives a constant view
Orbits in brief
A satellite in Geosynchronous and geostationary orbits takes one sidereal day to go around Earth, so it keeps pace with the ground below. A rocket cannot carry a heavy satellite straight there. It drops it into an elongated Geosynchronous transfer orbit, and the satellite's own engine does the final climb.
- 1Lift-offGSLV-F17 leaves Sriharikota's Second Launch Pad at 2.55 a.m. on 4 September 2026.
- 2Cryogenic stage burnThe liquid hydrogen and liquid oxygen third stage gives the final push.
- 3InjectionEOS-05 separates into a sub-geosynchronous transfer orbit, reported at about 171 km by 31,026 km.
- 4Orbit raisingThe satellite fires its own engine near the high point to circularise the orbit.
- 5On stationIt settles near 36,000 km and starts imaging after tests.
The rocket
The GSLV and its cryogenic stage is ISRO's rocket for transfer orbits. It stands 51.7 metres tall and weighs 420.5 tonnes at lift-off. Its cryogenic stage failed on GSLV-F10 in August 2021, taking GISAT-1 with it, so a clean flight mattered.
Seeing in hundreds of colours
A normal camera records three broad colours. Hyperspectral imaging splits light into hundreds of narrow bands, so each material (dry soil, stressed crop, smoke, dust) shows a distinct fingerprint. That is why EOS-05 can be useful for crop stress, fires and mineral dust even at coarse resolution.
Go deeper
In one line: India now has an imaging satellite that will watch the country from about 36,000 km, trading fine detail for a picture every few minutes.
Why it matters for UPSC
Space technology and its uses in disaster management and agriculture are regular GS3 themes. Prelims asks about orbits, launch vehicles and propellants.
The core idea
EOS-05 will sit in Geosynchronous and geostationary orbits, reached via a Geosynchronous transfer orbit. It was carried by the GSLV and its cryogenic stage, whose success mattered after the 2021 failure. Its instruments use Hyperspectral imaging to tell apart crops, soil, dust and smoke.
Numbers and dates to remember
- Launch: 2.55 a.m., 4 September 2026, Second Launch Pad, Sriharikota.
- GSLV-F17: 19th GSLV flight; 51.7 m tall; 420.5 tonnes.
- EOS-05: 2,367 kg.
- Imagers: 6-channel VNIR at 42 m; 158-channel VNIR at 318 m; 256-channel SWIR at 191 m.
- Revisit: selected areas every 5 minutes, all of India every 30 minutes.
- Earlier losses: GSLV-F10/GISAT-1 (August 2021), PSLV-C61 (May 2025), PSLV-C62 (12 January 2026).
Where to go next
- Geosynchronous and geostationary orbits: why a satellite can hover over one region.
- Geosynchronous transfer orbit: how heavy satellites reach 36,000 km.
- GSLV and its cryogenic stage: India's rocket for high orbits.
- Hyperspectral imaging: seeing materials by their colour fingerprint.
Go deeper: what a geo-imager adds, and what it cannot do
What it adds. India's remote sensing fleet has mostly flown in low orbits. Those satellites give sharp images but see a given spot only once every few days. For a cyclone making landfall, a flood wave moving down a river or a forest fire spreading, that is too slow. A geo-imager in Geosynchronous and geostationary orbits can stare at the same area and refresh the image every five minutes. Weather satellites such as the INSAT-3D series already do this for clouds; EOS-05 brings a similar rhythm to land imaging.
What it cannot do. At 36,000 km, even the best camera on EOS-05 resolves 42 metres, too coarse to see individual buildings or small fields. Its Hyperspectral imaging channels are coarser still (191 and 318 m). So it complements, and does not replace, fine-resolution satellites like Cartosat.
The launch story. A clean flight by the GSLV and its cryogenic stage matters because the vehicle's record includes the 2021 loss of GISAT-1. ThePrint reported that this time the cryogenic stage overperformed, leaving EOS-05 in a higher Geosynchronous transfer orbit than planned; if confirmed, the satellite needs less of its own fuel to reach station, which can extend its working life.
Institutional angle. After failures in May 2025 and January 2026, a successful launch restores confidence ahead of other planned missions, and shows why failure analysis committees and staged return-to-flight matter.
Geosynchronous and geostationary orbits
Why a satellite can hover over one region.
In one line: A geosynchronous satellite goes round Earth once a day; if it also sits over the Equator in a circular orbit, it looks fixed in the sky and is called geostationary.
The idea from zero
The higher a satellite flies, the slower it goes around Earth. At about 35,786 km above the surface, one orbit takes one sidereal day (about 23 hours 56 minutes), the same time Earth takes to rotate. Such an orbit is geosynchronous. If the orbit is circular and lies exactly over the Equator, the satellite stays above one point: this special case is geostationary. Communication and weather satellites use it.
Why it is in the news
EOS-05 is India's first imaging satellite for this orbit. Staying over India lets it image selected areas every five minutes.
Where to go next
Geosynchronous transfer orbit
How heavy satellites reach 36,000 km.
In one line: A geosynchronous transfer orbit (GTO) is an elongated orbit whose low point is near Earth and whose high point is near geosynchronous height.
How it works
It takes a lot of energy to put a satellite directly into a circular orbit at 36,000 km. So rockets usually release the satellite into a GTO. The satellite then fires its own engine, called a liquid apogee motor, at the high point (apogee) several times. Each burn raises the low point until the orbit becomes circular. A sub-GTO has a lower apogee than a standard GTO, so the satellite has to do more of the climbing itself.
Why it is in the news
GSLV-F17 put EOS-05 into a sub-GTO. ThePrint reported an achieved apogee of about 31,026 km against a planned 28,934 km, which saves the satellite fuel.
Where to go next
GSLV and its cryogenic stage
India's rocket for high orbits.
In one line: The Geosynchronous Satellite Launch Vehicle is a three-stage ISRO rocket whose top stage burns liquid hydrogen and liquid oxygen.
The stages
The first stage is a large solid motor with four liquid strap-on boosters. The second stage uses the liquid-fuelled Vikas engine. The third is the cryogenic upper stage. Cryogenic propellants are gases cooled until they turn liquid (hydrogen at about minus 253 degrees Celsius), and they give more thrust per kilogram than other fuels, which is why they are used for high orbits. Mastering this technology took ISRO many years, and early GSLV flights had several failures.
Why it is in the news
GSLV-F17 was the 19th GSLV flight. The cryogenic stage failed on GSLV-F10 in August 2021, losing GISAT-1; this time it reportedly performed better than planned.
Where to go next
Hyperspectral imaging
Seeing materials by their colour fingerprint.
In one line: Hyperspectral imaging records light in hundreds of narrow, adjacent wavelength bands, so every pixel carries a detailed spectrum.
The idea from zero
A phone camera records three broad bands: red, green and blue. A multispectral sensor records a handful. A hyperspectral sensor records a hundred or more. Different materials reflect light differently at each wavelength, so the spectrum works like a fingerprint that can separate healthy from stressed crops, identify minerals or detect smoke and dust. The cost is data volume and, usually, coarser spatial detail.
Why it is in the news
EOS-05 carries a 158-channel imager in the visible and near-infrared (318 m) and a 256-channel short-wave infrared imager (191 m), alongside a 6-channel camera at 42 m.
Where to go next
Take the 5 September 2026 quiz: 24 Prelims-style questions with answers