SOLAR SYSTEM

Detailed explanation-1: -Comets are cosmic snowballs of frozen gases, rock, and dust that orbit the Sun.

Detailed explanation-2: -The first, and the only part that is constantly visible, is the comet nucleus. This is the central part of the comet and the only part that is solid. It consists of varying proportions of rock, dust, ice and gas that give comets their “dirty snowball” reputation.

Detailed explanation-3: -Orbit of a Comet. Comets go around the Sun in a highly elliptical orbit. They can spend hundreds and thousands of years out in the depths of the solar system before they return to Sun at their perihelion.

Detailed explanation-4: -The comet nucleus is the dirty snowball that is essentially the entire comet when it is frozen and far from the Sun. The coma is a large, dusty atmosphere surrounding the nucleus, made up of sublimated gas mixed with dust.

Detailed explanation-5: -Sungrazing comets are a special class of comets that come very close to the sun at their nearest approach, a point called perihelion. To be considered a sungrazer, a comet needs to get within about 850, 000 miles from the sun at perihelion.

Detailed explanation-6: -As a comet approaches our Sun, it begins to heat up and the ice begins to sublimate-to change from a solid to a gas with no liquid stage. Some of the dust is left behind as the ice sublimates. It forms a dark, protective crust on the surface of the nucleus and slows the melting.