With reference to India’s satellite launch vehicles, consider the following statements:

1. PSLVs launch the satellite 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 three 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?

The correct option is 1 only.

Detailed Analysis of the Statements:

Statement 1 is correct:
Polar Satellite Launch Vehicle (PSLV) is primarily designed to launch Earth-observation/resources monitoring satellites into Sun-Synchronous Polar Orbits (SSPO). On the other hand, Geosynchronous Satellite Launch Vehicle (GSLV) is designed primarily to launch heavier communication satellites into Geostationary Transfer Orbit (GTO) and Geosynchronous Orbits.

Statement 2 is incorrect:
Satellites that appear to remain permanently fixed in the same position in the sky are in Geostationary Orbit (GEO). Communication satellites launched into GEO (typically by GSLV) exhibit this behavior. Satellites launched by PSLV generally orbit in polar/sun-synchronous orbits and move across the sky relative to a fixed ground location rather than remaining stationary.

Statement 3 is incorrect:
GSLV Mk III (now known as LVM3) is a three-stage launch vehicle consisting of:
- First stage: Two S200 solid rocket boosters (solid motors).
- Second stage: L110 core liquid stage (liquid engines).
- Third stage: C25 cryogenic upper stage.
It does not have four stages, nor does it use solid motors in the third stage.

Therefore, only statement 1 is correct.