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Also known as the gas tail, the ion tail is made up of gases that have been ionized by solar ultraviolet radiation. It points directly away from the Sun, as these ions are swept away by the solar wind.

The hydrogen envelope is a huge, but diffuse, cloud of neutral hydrogen gas that is released by the comet's nucleus and surrounds the coma. It is often too faint to see with the naked eye but can be detected with special instruments.

The nucleus is the solid core of the comet, consisting mostly of ice and dust. It's the central part from which the comet's coma and tails emanate when it is heated by the Sun.

The coma is the nebulous envelope around the nucleus of a comet, formed when the comet passes close to the Sun and heats up. It is composed of gas and dust that the comet releases, creating a visible atmosphere.