Question

Which of the following is an important difference between comets and asteroids?

a) asteroids formed much earlier than comets
b) asteroids never outgas, but comets do
c) asteroids have high orbital eccentricities while comets typically have low eccentricities
d) asteroids typically orbit much closer to the Sun than comets do
e) asteroids are made of ice and comets are made of a mix of ice and rock

Answer 1

The key difference between comets and asteroids is that asteroids, being rocky or metallic, do not outgas, whereas comets, which are made of icy and volatile materials, do outgas when they approach the Sun.

Step-by-step explanation:

The important difference between comets and asteroids lies in their composition and behavior as they approach the Sun. Asteroids are mostly rocky or metallic and contain little volatile material, meaning they show no signs of an atmosphere or activity like cometary outgassing. On the other hand, comets are composed of icy materials and various volatile substances mixed with solid grains. When comets come near the Sun, the increase in temperature causes some of this icy material to vaporize, forming a large head of gas, and often a tail, which is why they're known to outgas.

Referring to the options given in the student's question, the correct answer that highlights an important difference is:

b) asteroids never outgas, but comets do.