RAS question
The IRS-1A satellite, launched in 1988, was India's first operational remote sensing satellite. Which launch vehicle was used to place it in orbit?
Correct answer: (A) Soviet Vostok rocket.
IRS-1A, India's first operational remote sensing satellite, was placed in orbit by the Soviet Vostok launch vehicle from Baikonur on 17 March 1988.
Explanation
IRS-1A was launched on 17 March 1988 from the Soviet Cosmodrome at Baikonur, and ISRO's mission page lists its launch vehicle as Vostok. The satellite was placed in a polar sun-synchronous orbit, which mattered because IRS-1A was designed for operational remote sensing rather than a short experimental flight. India did not yet have a launch vehicle capable of putting such satellites into polar sun-synchronous orbit, so the Soviet Vostok vehicle was used. ISRO identifies the mission as Operational Remote Sensing and records the orbit as 904 km polar sun-synchronous. The launch vehicle was Vostok, not an Indian launcher or Ariane.
Why the other options are wrong
- (B) Ariane-4 is wrong because the ISRO mission page records the IRS-1A launch vehicle as Vostok, and Ariane was not used for this launch.
- (C) PSLV-C1 is wrong because IRS-1A was launched in 1988, while PSLV-C1 is ruled out for this launch and the ISRO page lists Vostok as the launch vehicle.
- (D) SLV-3 is wrong because it was associated with small experimental satellite launches, whereas IRS-1A was an operational remote sensing satellite launched by Vostok.
Concept
This tests India's early remote-sensing programme and the launch-vehicle gap before indigenous capability matured for polar sun-synchronous missions. RAS repeats such questions because space milestones connect Science and Technology with institutions, applications and national capability building.