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?
Answer & explanation
Answer: (a) 1 only
Only statement 1 is correct. PSLV is ISRO's workhorse for earth-observation (remote-sensing) satellites in low, sun-synchronous polar orbits, while GSLV's main job is communication satellites for geosynchronous transfer orbit. GSLV Mk III has three stages, not four.
- ✓ 1. Government of India's science portal says PSLV is designed mainly to deliver earth-observation or remote-sensing satellites, and VSSC says GSLV places INSAT and GSAT communication satellites into geosynchronous transfer orbit.
- ✗ 2. A satellite looks fixed in the sky only if it is in geostationary orbit, about 35,786 km up. PSLV mainly puts satellites in polar orbits at 600-900 km, which sweep across the sky.
- ✗ 3. GSLV Mk III (LVM3) is a three-stage vehicle: two solid strap-on motors (S200), a liquid core stage (L110) and a cryogenic upper stage (C25). It has no fourth stage.
- • Since then ISRO now names this rocket LVM3 (GSLV Mk III); the configuration described on ISRO's LVM3 page is the same three-stage design.
Remember · PSLV: earth-observation satellites into polar sun-synchronous orbits. GSLV: communication satellites into geostationary transfer orbit. GSLV Mk III (LVM3): three stages.
Sources
- Indigenous Launching Vehicles for Space Expedition, India Science and Technology portal (Government of India) ↗ “It is designed mainly to deliver the “earth-observation” or “remote-sensing” satellites with lift-off mass of up to about 1750 Kg to Sun-Synchronous circular polar orbits of 600-900 Km altitude.”
- GSLV, Vikram Sarabhai Space Centre (ISRO) ↗ “Geosynchronous Satellite Launch Vehicle (GSLV) is capable of placing 2.3 ton class of satellites like the INSAT & GSAT communication satellites and INRSS & IDRSS series of spacecrafts into Geosynchronous Transfer Orbit (GTO).”
- LVM3 (Geosynchronous Satellite Launch Vehicle Mk III), ISRO ↗ “LVM3 is configured as a three stage vehicle with two solid strap-on motors (S200), one liquid core stage (L110) and a high thrust cryogenic upper stage (C25).”
Question and answer: UPSC's official GS Paper I (2018, Series A) — paper ↗ · answer key ↗. Explanation: Minimalist IAS, checked 30 Sept 2026 (how we verify). ·