2022 · GS Paper 3 · Q15 · 15 marks
Launched on 25th December, 2021, James Webb Space Telescope has been much in the news since then. What are its unique features which make it superior to its predecessor Space Telescopes ? What are the key goals of this mission ? What potential benefits does it hold for the human race ?
In short
The James Webb Space Telescope surpasses Hubble through a far larger segmented mirror, infrared vision and a cold orbit at L2, and aims to see the first galaxies, star and planet birth and exoplanet atmospheres. In 2022 it made the first clear detection of carbon dioxide in an exoplanet atmosphere, on WASP-39b.
Model answer
Ghissu Editorial · Verified 4 Oct 2026 · 284 words
Light and Infrared
Eighteen gold-coated beryllium segments give about six times Hubble's collecting area, and infrared sight both catches stretched light from the earliest galaxies and pierces dust around newborn stars.
Cold, Distant Orbit
At L2, about 1.5 million km away, a five-layer sunshield cools the instruments below about 50 K, while NIRSpec takes spectra of up to 100 objects at once.
Early Universe
It hunts the first galaxies, confirming JADES-GS-z14-0 in 2024, and traces how galaxies assembled.
Stars, Planets, Life
It looks into stellar nurseries and reads exoplanet atmospheres, detecting carbon dioxide on WASP-39b in 2022.
Knowledge and Life
Unexpectedly bright early galaxies are forcing cosmologists to revise models, and its spectra can test rocky-planet atmospheres for biosignatures such as methane and oxygen.
Defence and Spin-offs
It observed the DART asteroid impact in 2022, and its cryogenic and precision-optics technologies reach industry.
Indian Use
Indian astronomers should win observing time and pair it with AstroSat data, while completing India's share in the Thirty Meter Telescope.
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Question from the official UPSC Civil Services (Main) Examination 2022 paper. Answer written by Ghissu's engine and checked against our editorial standards. Found an error? Tell us and we correct it within 48 hours.