UPSC Mains 2017 GS Paper 1 Q5: model answer
How does the Juno Mission of NASA help to understand the origin and evolution of the Earth?
What the question wants
Explain how NASA's Juno mission to Jupiter helps understand Earth's origin and evolution.
How to structure it
How does ... help: link Jupiter science to Earth.
- Mission basics
- Findings
- Relevance to Earth
How to think it through
Studying Jupiter to understand Earth sounds odd, like studying an elder sibling to understand yourself. Jupiter formed first and is mostly unchanged since the solar system's birth. Its make-up is a time capsule.
Model answer
Juno, launched by NASA in 2011, entered orbit around Jupiter on 4 July 2016. Jupiter, the oldest and largest planet, still holds much of the original material of the solar nebula.
What Juno studies
- Water and ammonia in Jupiter's atmosphere; its core; gravity and magnetic fields; auroras; and, in its extended mission, the moons Ganymede, Europa and Io.
How it helps understand Earth
- Origin of the solar system: the amount of water tells us where and how Jupiter formed, and whether it migrated, which shaped the inner planets including Earth.
- Delivery of water: Jupiter's gravity may have scattered water-rich bodies towards Earth.
- Planetary cores and magnetism: a 'fuzzy' core and a strong magnetic field help compare with Earth's dynamo.
- Atmospheric dynamics: giant storms and jet streams test the physics that also runs Earth's weather.
- Shield role: Jupiter's gravity deflects comets, affecting impacts on early Earth and possibly the survival of early life.
Juno thus helps reconstruct the conditions under which Earth formed and offers a model for studying giant planets found around other stars.
Draw: Solar system sketch with Jupiter's gravity deflecting comets.
Keywords, cases and data to drop in
Juno 2011–2016, solar nebula, gas giant, magnetosphere, dilute core, planetary migration.
Where most answers lose marks
- Writing only about Jupiter. Each point must return to Earth.
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Question text as printed in the official UPSC Civil Services (Main) question paper. The model answer is original Battle IAS work; use it to learn structure, not to memorise.
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