GENERAL KNOWLEDGE

Detailed explanation-1: -Coma. As a comet gets closer to the sun, the ice on the surface of the nucleus begins turning into a gas via a process called sublimation, forming a cloud around the comet known as the coma.

Detailed explanation-2: -As a comet gets closer to the Sun, the ice in the comet heats up. Some of this ice turns into a gas. The gas (plus dust and some water) forms a cloud around the nucleus, called a coma. You can think of the coma as the comet’s atmosphere. The coma can be as large as a planet!

Detailed explanation-3: -Surrounding the coma is an invisible layer of hydrogen called the hydrogen envelope; the hydrogen may come from water molecules. It usually has an irregular shape because it is distorted by the solar wind. The hydrogen envelope gets bigger as the comet approaches the sun.

Detailed explanation-4: -The nucleus is a solid body typically a few kilometres in diameter and made up of a mixture of volatile ices (predominantly water ice) and silicate and organic dust particles. The coma is the freely escaping atmosphere… …of materials then forms the cometary coma, the comet’s atmosphere.