"GSLV-F17 Successfully Launches India's First Geosynchronous Earth Observation Satellite"
Geosynchronous Orbit (GSO)
orbit at ~36,000 km where a satellite matches Earth's rotation speed, staying fixed over one region.
Geosynchronous Transfer Orbit (GTO)
intermediate elliptical orbit a launch vehicle deposits a satellite into before it raises itself to final GSO.
India's earth observation programme has grown steadily since the launch of the first Indian Remote Sensing (IRS) satellites. These satellites operate in Low Earth Orbit (LEO), typically a few hundred kilometres above Earth. From LEO, a satellite completes multiple orbits each day and captures imagery of any given location only during its periodic passes. This periodic revisit model works well for many applications, such as crop mapping or land-use surveys, where daily or weekly snapshots are sufficient.
However, LEO satellites cannot watch a single region continuously. For real-time monitoring of fast-moving events, a flood spreading across a river basin, a forest fire advancing, or a developing weather system, continuous observation is far more valuable. This gap is what geosynchronous orbit (GSO) satellites are designed to fill. At roughly 36,000 km above Earth, a satellite in geosynchronous orbit moves at the same angular speed as Earth's rotation, allowing it to remain stationary relative to a fixed point on the ground and observe the same region without interruption.
India already uses geosynchronous orbit for communication and meteorological satellites under the INSAT and GSAT series. The GSLV (Geosynchronous Satellite Launch Vehicle) was developed specifically to carry heavier payloads to this higher orbit. The GSLV uses a cryogenic upper stage, an engine that burns liquid hydrogen and liquid oxygen, which provides the high specific impulse needed to reach geosynchronous transfer orbit. Mastering cryogenic technology took ISRO many years and several failures, earning the GSLV the informal label of a difficult rocket to tame.
The GSLV-F17 mission carried EOS-05, India's first dedicated imaging satellite placed in geosynchronous orbit. Unlike earlier earth observation satellites in LEO, EOS-05 will remain fixed relative to India's landmass, enabling continuous, high-frequency imaging of large areas. This is a qualitatively different capability from what LEO satellites offer.
The satellite was first placed in a geosynchronous transfer orbit (GTO) at an altitude of about 190 km after launch. From GTO, the satellite's own onboard propulsion system performs a series of orbit-raising manoeuvres over several days, gradually increasing the orbit's apogee until the satellite reaches its final geosynchronous orbit at approximately 36,000 km. This two-step process, launch vehicle delivers to GTO, satellite raises itself to final orbit, is standard for heavy geostationary and geosynchronous missions.
EOS-05 has a designed mission life of 10 years. Its primary applications include monitoring natural disasters such as floods and forest fires, tracking agriculture and forestry changes, and supporting defence situational awareness. …
With reference to India's satellite launch vehicles, consider the following statements :
1.PSLVs launch the satellites useful for Earth resources monitoring whereas GSLVs are designed mainly to launch communication satellites.
2.Satellites launched by PSLV appear to remain permanently fixed in the same position in the sky, as viewed from a particular location on Earth.
3.GSLV Mk III is a four-staged launch vehicle with the first and third stages using solid rocket motors; and the second and fourth stages using liquid rocket engines.
Which of the statements given above is/are correct?
In which of the following activities are Indian Remote Sensing (IRS) satellites used?
1.Assessment of crop productivity
2.Locating groundwater resources
3.Mineral exploration
4.Telecommunications
5.Traffic studies
Select the correct answer using the code given below.
With reference to India's Geosynchronous Satellite Launch Vehicle (GSLV), consider the following statements:
1.The first stage of GSLV uses solid propellant.
2.The second stage of GSLV uses liquid propellant.
3.The third stage of GSLV uses a cryogenic engine burning liquid hydrogen and liquid oxygen.
4.GSLV Mk III is a four-stage rocket with two cryogenic stages.
How many of the above statements are correct?
Consider the following statements regarding EOS-05 and India's earth observation satellite programme:
1.EOS-05 is India's first dedicated imaging satellite placed in geosynchronous orbit.
2.Satellites in geosynchronous orbit provide periodic revisit coverage of a region, unlike LEO satellites which provide continuous coverage.
3.EOS-05 was launched by the GSLV-F17 rocket, which uses a cryogenic engine in its third stage.
Which of the statements given above is/are correct?
Match the following earth observation satellite orbit types with their characteristics:
List I (Orbit Type) — List II (Characteristic)
A.Low Earth Orbit (LEO) — 1. Satellite remains stationary relative to Earth; enables continuous regional imaging
B.Geosynchronous Orbit (GSO) — 2. Satellite completes multiple orbits per day; provides periodic revisit coverage
C.Geosynchronous Transfer Orbit (GTO) — 3. Intermediate elliptical orbit used before a satellite raises itself to final geosynchronous orbit
Select the correct answer using the code given below:
Which of the following best explains why India developed its own cryogenic engine technology for the GSLV rocket?
Consider the following statements regarding India's space sector policy and institutional framework:
1.IN-SPACe (Indian National Space Promotion and Authorisation Centre) is the regulatory body for private sector participation in India's space programme.
2.The Indian Space Policy 2023 formally opened India's space sector to non-governmental entities.
3.The Indian Space Association (ISpA) is a government body under the Department of Space.
Which of the statements given above is/are correct?
Want the full note, Prelims Facts & MCQ answers?
Create a free account — takes less than a minute.
Create free account