In the aerospace context, a coma is a cloud of gas and dust that surrounds the nucleus of a comet as it approaches the sun. The coma is created as the sun warms the icy surface of the comet's nucleus, causing volatile materials to sublimate and create a cloud of gas and dust that surrounds the nucleus.
When a comet is far from the sun, the coma is not visible and the comet appears as a small, faint object. But as the comet approaches the sun, the coma becomes larger and more prominent, and the comet may appear to have a "tail" of gas and dust pointing away from the sun.
Examples of comets that have been studied in the aerospace context include:
- Halley's Comet: This comet, which is visible from Earth every 76 years, was studied by the European Space Agency's Giotto spacecraft in 1986.
- Comet Hale-Bopp: This comet, which was visible from Earth in 1997, was observed by several spacecraft and ground-based telescopes.
- Comet 67P/Churyumov-Gerasimenko: This comet was studied by the European Space Agency's Rosetta spacecraft, which orbited the comet and landed a probe on its surface.
Comets are interesting objects for the aerospace industry as they can provide valuable information about the formation and evolution of the solar system, as well as the composition of the early solar system. The study of comets and their coma can also help scientists to understand the properties and behavior of volatiles in space and the potential origins of water and organics in the inner solar system.