Comets are the small celestial snowballs of frozen gases, rocks, and dust that orbit the Sun.

What are Comets?
Comets are celestial bodies that consist of a nucleus, a coma, and a tail. They are often referred to as "dirty snowballs" because they are made up of a mixture of frozen gases, rocks, and dust.

Composition of Comets:
1. Nucleus: The nucleus is the solid core of a comet. It is made up of various ices, such as water, carbon dioxide, methane, and ammonia, mixed with rocks and dust. The nucleus is typically just a few kilometers in diameter.

2. Coma: As a comet approaches the Sun, the heat causes the ices in the nucleus to vaporize and create a glowing cloud around the nucleus called the coma. The coma can be thousands or even millions of kilometers in diameter.

3. Tail: The intense heat and radiation from the Sun push the coma and the dust particles away from the nucleus, creating a tail that extends away from the Sun. The tail can be hundreds of thousands or even millions of kilometers long. There are two types of tails: gas tails, which are composed of ionized gas, and dust tails, which are composed of small dust particles.

Orbit of Comets:
Comets orbit the Sun in highly elliptical orbits that can take them from the outer regions of the solar system to the inner regions. When a comet is far from the Sun, it remains in a dormant state, with its nucleus and coma frozen. However, as it gets closer to the Sun, the heat causes the ices to vaporize and the coma and tail to form.

Observing Comets:
Comets are often visible from Earth when they come close to the Sun and their tails become illuminated by sunlight. Astronomers study comets to learn more about the early solar system and the composition of the outer regions of the solar system.

Conclusion:
Comets are fascinating celestial objects that consist of a nucleus, coma, and tail. They are composed of frozen gases, rocks, and dust and orbit the Sun in highly elliptical orbits. Observing and studying comets helps scientists understand the formation and evolution of the solar system.

The small celestial snowball of frozen[gases, rocks and dust that orbit the sun is known as a comet.