Comet

Comets are small, icy, dusty celestial bodies that orbit the Sun. Most comets are thought to originate in the Oort Cloud, a vast reservoir of icy bodies thought to surround our solar system at a distance of about a light-year. As a comet approaches the Sun, the Sun's heat vaporizes the comet's icy surface, causing it to release gas and dust. This gas and dust forms a tail that points away from the Sun.

Definition

A comet is a small, icy, dusty celestial body that, as it approaches the Sun, warms up and releases gas and dust. This gas and dust forms a tail that points away from the Sun. Comets orbit the Sun just like planets do, but their orbits are much more elliptical.

History

Comets are small, icy, dusty celestial bodies that orbit the Sun. Most comets are thought to originate in the Oort Cloud, a vast reservoir of icy bodies thought to surround the Sun at a distance of about a light-year. As a comet approaches the Sun, the Sun's heat vaporizes the comet's icy surface, causing it to release gas and dust. This gas and dust forms a tail that points away from the Sun.

Composition

Comets are small, icy, dusty celestial bodies. They orbit the Sun in long, elliptical paths and are believed to be leftovers from the formation of the solar system. A comet's nucleus is its most distinctive feature. It is a small, dark, and very dusty body. The coma is the bright, gaseous envelope that surrounds the nucleus. The coma is usually much larger than the nucleus and can be as large as the Sun. The coma is made up of gas and dust that has been blown off of the nucleus by the Sun's heat.

Structure

Comets are small, icy, dusty celestial bodies. They orbit the Sun in long, elliptical paths and are believed to be leftovers from the formation of the solar system. A comet typically has a nucleus, or head, which is a small, dark, and very dusty object. The coma is the bright atmosphere that surrounds the nucleus. The coma is usually much larger than the nucleus. The tail is the long, often curved, stream of gas and dust that points away from the Sun.