Tail

Definition

The tail of a comet is a stream of gas and dust particles that extends from the comet's nucleus, often millions of kilometers long. The tail forms when the comet is heated by the Sun, causing material to vaporize and be pushed away by solar wind and radiation pressure.

5 Must Know Facts For Your Next Test

1. A comet typically has two types of tails: a dust tail and an ion (gas) tail.
2. The dust tail is curved and follows the comet’s orbit, while the ion tail points directly away from the Sun due to interactions with the solar wind.
3. The length of a comet's tail can extend up to several million kilometers.
4. Tails are visible when a comet approaches the inner solar system where solar radiation causes sublimation of its icy components.
5. Comet tails always point away from the Sun, regardless of the direction in which the comet is traveling.

Review Questions

Related terms

nucleus:

The solid central part of a comet, composed mainly of ice and rock.

coma: A cloud of gas and dust that surrounds the nucleus of a comet when it is close to the Sun.

solar wind:

A stream of charged particles released from the upper atmosphere of the Sun, influencing various cosmic phenomena including comet tails.