Solar System and Evolution of Earth: UPSC Previous Year Questions (Geography)
3 previous year UPSC Prelims questions on Solar System and Evolution of Earth (Geography). Choose an option to see the answer and explanation.
Explanations state facts as of the year each question was asked; words like “recently” refer to that year.
Showing 1–3 of 3 questions
UPSC 1997Geography · Solar System and Evolution of Earth
Q1. The group of small pieces of rock revolving round the Sun between the orbits of Mars and Jupiter are called:
Explanation
Option (d) is correct:
Asteroids are rocky objects that orbit the Sun, primarily found in the Asteroid Belt between Mars and Jupiter. They are remnants from the early formation of the Solar System. They vary in size from small pebbles to Ceres, which is nearly 946 km in diameter and classified as a dwarf planet. Options (a), (b) and (c) are incorrect:
Meteors do not revolve around the Sun in a fixed orbit like asteroids. They are small space debris or fragments of asteroids or comets that enter Earth’s atmosphere and burn up due to friction with the air, producing a bright streak of light (commonly called a shooting star). Comets are not confined to the region between Mars and Jupiter. Comets are icy celestial bodies that originate from the Kuiper Belt or Oort Cloud (far beyond Neptune). They follow highly elliptical orbits around the Sun and develop a glowing coma and a tail when they approach the Sun due to ice subli-mation. Meteorites are meteors that survive their passage through Earth’s atmosphere and land on Earth’s surface. Unlike asteroids they do not orbit the Sun.
UPSC 1997Geography · Solar System and Evolution of Earth
Q2. Which one of the following stars is nearest to the Earth?
Explanation
The Sun, positioned at the center of the Solar System, is the closest star to Earth, with a distance of roughly 93 million miles (approximately 8 light-minutes). Its proximity makes it crucial for life on Earth.
Option (d) is incorrect: Sirius, also known as the Dog Star, is one of the brightest stars visible from Earth. However, it is located approximately 8.6 light-years away, making it significantly farther than the Sun.
UPSC 1997Geography · Solar System and Evolution of Earth
Q3. Which one of the following conditions is most relevant for the presence of life on Mars?
Explanation
The presence of ice caps and frozen water is the most critical condition for the potential existence of life on Mars. Water is fundamental for life as we know it. The presence of frozen water (ice caps) on Mars suggests the possibility of liquid water under certain conditions, making it the most crucial factor for life. Recent discoveries of underground water reservoirs beneath the Martian surface further highlight its importance.
Additional insight:
Mars, the fourth planet from the Sun, is often called the "Red Planet" due to its iron-rich, reddish surface. It has a thin atmosphere primarily composed of carbon dioxide, with traces of nitrogen and argon. Mars has polar ice caps, large volcanoes like Olympus Mons, and a canyon system known as Valles Marineris. The planet experiences seasons, dust storms, and temperature fluctuations. Scientific interest in Mars stems from evidence of ancient rivers, lakes, and possible subsurface water, making it a key target in the search for past or present life.
Answer key for these questions
Q
UPSC year
Correct answer
1
1997
(d) Asteroids
2
1997
(c) Sun
3
1997
(c) Occurrence of ice caps and frozen water
Frequently asked questions
How many previous year UPSC questions are there on Solar System and Evolution of Earth?
This page covers 3 previous year UPSC Prelims GS Paper-I questions on Solar System and Evolution of Earth (Geography), asked from 1996 to 2025. Each has the correct answer and an explanation.
How should I use previous year UPSC questions for Prelims?
Attempt each question first, then open the answer and read the explanation for every option. Repeat by chapter, and track which statements UPSC reuses across years. Previous year questions show the exam pattern and difficulty level.
Which years are covered for Solar System and Evolution of Earth?
Questions on Solar System and Evolution of Earth (Geography) are available for 12 years, from 1996 to 2025. Use the Year filter to practise a single paper.
