SSC CGL 2025 Tier-I · 19 September 2025, Shift 2 · General Awareness · Question 24 of 100

We transcribed this text from the pictures on a candidate's response sheet for this shift; the answer is the key SSC colour-marked on that sheet. Solution last reviewed 13 September 2026.

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SSC does not publish CGL question papers or a public answer key. From 2025 the candidate response sheet prints every question and option as a picture, so the text here is transcribed from those pictures for this shift and checked against them independently; where the layout carries meaning, the picture is shown as well. Each answer is the key SSC colour-marked on that sheet. SSC released a tentative key for challenge and later its final one, both only to candidates behind a login, and the sheet does not say which of the two it carries. The solutions are written by UnlockIAS.

Which ISRO mission first discovered lunar hydration?

(a)Chandrayaan-1
(b)Chandrayaan-2
(c)Chandrayaan-3
(d)Chandrayaan-4

Answer

Why

Correct — A. Chandrayaan-1, launched on 22 October 2008, carried NASA's Moon Mineralogy Mapper (M3).

M3 found that parts of the lunar surface absorb light at wavelengths linked to water and hydroxyl. The result was published in Science in September 2009.

The detection came from India's first Moon mission → option (a).

Why the others are wrong

(b)
Chandrayaan-2 — Chandrayaan-2 launched in July 2019, a decade after M3's 2009 result. It came too late to be first.
(c)
Chandrayaan-3 — Chandrayaan-3 is known for its landing near the lunar south pole on 23 August 2023, fourteen years after the hydration result.
(d)
Chandrayaan-4 — Chandrayaan-4 had not flown by the time of this exam. It is a planned sample-return mission, so it has no discovery to its name.

Concept

Chandrayaan-1 was India's first mission to the Moon, launched by PSLV-C11 from Sriharikota. It mapped the Moon from a 100 km orbit with 11 instruments built in India, the USA, the UK, Germany, Sweden and Bulgaria.

M3, a NASA imaging spectrometer, was one of the foreign payloads. Water and hydroxyl leave absorption features in reflected infrared light, and M3 picked them up on the surface, especially in the polar regions.

The mission ended when contact was lost on 29 August 2009.

NASA noted that data from its Cassini and EPOXI spacecraft helped confirm the finding. The detection itself came from M3 on Chandrayaan-1.

Key facts

Chandrayaan-1 was launched on 22 October 2008 by PSLV-C11 from Sriharikota.
NASA's Moon Mineralogy Mapper (M3) on Chandrayaan-1 detected water and hydroxyl on the lunar surface, reported in September 2009.
Chandrayaan-1 carried 11 scientific instruments from India, the USA, the UK, Germany, Sweden and Bulgaria.
Chandrayaan-3 landed near the lunar south pole on 23 August 2023.

Study next

Chandrayaan-3: the Vikram lander and Pragyan roverMangalyaan (Mars Orbiter Mission), India's first interplanetary missionChandrayaan-4 and lunar sample return

Common traps

Crediting the famous south-pole landing (Chandrayaan-3) with the water finding: that came from orbit in 2009.
Calling Chandrayaan-1 an interplanetary mission: the Moon is not a planet, and India's first interplanetary mission is Mangalyaan.

Chandrayaan-1 is also an option at 17 Sep 2025, 12:30, GA Q.24, which keys Mangalyaan as India's first interplanetary mission, and Chandrayaan-3's NASA-supplied reflector is asked at 15 Sep 2025, 12:30, GA Q.13.

Related PYQs

No directly related past PYQ was found.

Topic: General Policy — all 308 SSC CGL questions on it, every solved shift.