What is the difference between asteroids and comets?
1. Asteroids are small rocky planetoids, while comets are formed of frozen gases held together by rocky and metallic material.
2. Asteroids are found mostly between the orbits of Jupiter and Mars, while comets are found mostly between Venus and Mercury.
3. Comets show a perceptible glowing tail, while asteroids do not.
Which of the statements given above is/are correct?(2011)
a)1 and 2 only
b)1 and 3 only
c) 3 only
d) 1, 2 and 3
Answer: B
Asteroid orbit the Sun and are small bodies on the solar system. They are made up of metals and rocks and also consist of organic compounds. They are similar to comets but don’t have a coma-like comet. Asteroids tend to have shorter and elliptical orbits. Astronomers have discovered millions of asteroids, some that measure hundreds of kilometres across and some as small as dust particles.
Comets also orbit the Sun and are relatively small bodies of the solar system. When comets approach the sun, some part of their ice melts. When some parts of the ice melt, the other materials vaporise due to the heat of the sun. This results in a glowing halo that extends outwards as though sailing through space. The ice and compounds like ammonia and methane develop a fuzzy cloud-like shell known as the coma. This forms a notable difference between comets and asteroids.
Comets were formed farther away from the sun where the ice remained solid. Comets that approach the Sun lose material with its every orbit around the sun as its ice melts and vaporizes to form the tail known as the coma. Hence statement 2 is incorrect
