Here's a breakdown of what makes a comet:

* Ice and Dust: The nucleus of a comet is primarily made up of ice (frozen water, carbon dioxide, methane, ammonia) mixed with dust particles.

* Orbiting the Sun: Comets travel in highly elliptical orbits around the Sun.

* Tail Formation: As a comet gets closer to the Sun, the heat causes the ice to vaporize, creating a glowing cloud of gas and dust called a coma. The solar wind pushes this material away from the Sun, creating a long, visible tail.