SOLAR SYSTEM

Detailed explanation-1: -Comets are collections of rocky material and ices, sometimes referred to as “dirty snowballs”. One of their key features is their large abundance of so-called “volatile” compounds, things like carbon dioxide, water and noble gases that sublimate (change from solid to gas) very easily.

Detailed explanation-2: -They range from a few miles to tens of miles wide, but as they orbit closer to the Sun, they heat up and spew gases and dust into a glowing head that can be larger than a planet. This material forms a tail that stretches millions of miles. Comets are cosmic snowballs of frozen gases, rock, and dust that orbit the Sun.

Detailed explanation-3: -Comets are like “dirty snowballs” that have orbited the Sun since our Solar System formed, billions of years ago. A comet is really just a round chunk of ice and dust. The ball-like part of the comet is called the nucleus, and its long “tail” is called the coma.

Detailed explanation-4: -The nucleus is the solid, central part of a comet, once termed a dirty snowball or an icy dirtball. A cometary nucleus is composed of rock, dust, and frozen gases.

Detailed explanation-5: -A model of a comet’s nucleus, proposed by F. L. Whipple in 1949, and confirmed by the Giotto space probe to Halley’s Comet in 1986. According to this model, cometary nuclei consist of a relatively solid conglomerate of frozen ices and dust, rather than a loose ‘flying sandbank’ as suggested by an alternative model.