Previous Year Question
What is the difference between asteroids and comets?
Asteroids are small rocky planetoids, while comets are formed of frozen gases held together by rocky and metallic material.
Asteroids are found mostly between the orbits of Jupiter and Mars, while comets are found mostly between Venus and Mercury.
Comets show a perceptible glowing tail, while asteroids do not.
Which of the statements given above is/are correct?
Correct Answer: B
Detailed Solution
Statement 1 is correct: Asteroids are small celestial bodies composed mainly of rocky and metallic material. Comets contain frozen gases or ice, dust and rocky material. Both are ancient remnants left over from the formation of the Solar System.
Statement 2 is incorrect: Most asteroids are found in the main asteroid belt between Mars and Jupiter. Comets, however, are not found mostly between Venus and Mercury. The Kuiper Belt, located beyond Neptune, is a major source of short-period comets, while the extremely distant Oort Cloud is considered the source of long-period comets.
Statement 3 is correct: When a comet approaches the Sun, it becomes heated and its ice sublimates, releasing gas and dust. This produces a bright coma and dust and ion tails pointing away from the Sun. Ordinary asteroids do not develop such a perceptible glowing tail.