What is the main difference between a comet and an asteroid?

The main distinction between a comet and an asteroid lies in their composition. Comets are primarily composed of ice, dust, and rocky material, making them icy bodies that form in the outer regions of the solar system. When comets approach the Sun, the heat causes the icy components to sublimate, creating a glowing coma and a tail that always points away from the Sun due to solar winds.

In contrast, asteroids are mainly made up of rock and metal. They are found mostly in the inner solar system, particularly in the asteroid belt between Mars and Jupiter, and do not exhibit the same luminous features as comets since they lack significant amounts of volatile substances.

This fundamental difference in composition not only defines the physical characteristics of the two types of celestial bodies but also influences their behavior and appearance when observed from Earth. The details about their typical locations and sizes vary but do not capture this essential compositional difference, making the understanding of materials they are made of crucial in distinguishing between the two.