COMET

Comets are icy bodies that originate from the outer solar system, particularly the Kuiper Belt and the Oort Cloud, and they travel in highly elliptical orbits around the Sun. When a comet approaches the Sun, the heat causes its icy core, or nucleus, to release gas and dust, forming a glowing coma around the nucleus and a tail that points away from the Sun due to the solar wind. Comet tails can be millions of kilometers long and often consist of two parts: a dust tail and an ion tail, each influenced by different forces. Comets are composed of a mixture of water ice, frozen gases, dust, and organic compounds, and they are often described as "dirty snowballs." The most famous comet is Halley's Comet, which orbits the Sun every 76 years and is visible from Earth with the naked eye. Comets are believed to be remnants from the formation of the solar system, providing clues about its early history and the materials that contributed to the development of planets. The study of comets has been advanced by missions like ESA’s Rosetta, which landed a probe on comet 67P/Churyumov-Gerasimenko, revealing detailed information about its composition and behavior.

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