UPSC Prelims 2016 Q87: Science & Technology – Space Technology & Astronomy
With reference to ‘Astrosat’, the astronomical observatory launched by India, which of the
following statements is/are correct?
1. Other than USA and Russia, India is the only country to have launched a similar observatory
into space.
2. Astrosat is a 2000 kg satellite placed in an orbit at 1650 km above the surface of the Earth.
Select the correct answer
using the code given below.
- (a) 1 only
- (b) 2 only
- (c) Both 1 and 2
- (d) Neither 1 nor 2
Answer: (d) Neither 1 nor 2
Explanation
Astrosat
Astrosat is India's first dedicated multi-wavelength space observatory.
It was launched on 28 September 2015 by PSLV-C30.
| Statement | Verdict | Fact |
|---|---|---|
| 1. Other than USA and Russia, India is the only country to have launched a similar observatory into space | Incorrect | Japan and the European Space Agency have also launched space observatories |
| 2. Astrosat is a 2000 kg satellite placed in an orbit at 1650 km above the surface of the Earth | Incorrect | It weighs about 1,513 kg and orbits at about 650 km |
Key facts:
| Feature | Detail |
|---|---|
| Observes in | Ultraviolet, visible and X-ray bands at the same time |
| Orbit | Near-equatorial, low Earth orbit |
| Payloads | Five scientific instruments |
Answer: (d) Neither 1 nor 2.
Why each option is right or wrong
- (a) Incorrect. Japan and Europe have also launched space observatories.
- (b) Incorrect. Astrosat weighs about 1,513 kg and orbits at about 650 km.
- (c) Incorrect. Both statements are false: wrong claim of uniqueness and wrong figures.
- (d) CORRECT. Other agencies have such observatories, and the weight and orbit figures are wrong.
Key point
Astrosat (28 September 2015, PSLV-C30): India's first multi-wavelength space observatory; about 1,513 kg; 650 km near-equatorial orbit.
Remember
Astrosat = 1,513 kg at 650 km, launched 2015.
Common mistakes
- Accepting 'the only country' claims without checking Japan and Europe.
- Not noticing the altered figures: 2000 kg and 1650 km.
- Calling Astrosat India's Hubble; it is smaller and works mainly in X-ray and ultraviolet.
Exam tip
UPSC changes one digit: 650 km became 1650 km. Check every number.
Sources
- Indian Space Research Organisation — Astrosat mission
- Press Information Bureau — PSLV-C30 launches Astrosat (28 September 2015)