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- Comet - Wikipedia
A comet is an icy, small Solar System body that warms and begins to release gases when passing close to the Sun, a process called outgassing This produces an extended, gravitationally unbound atmosphere or coma surrounding the nucleus, and sometimes a tail of gas and dust gas blown out from the coma
- Comets - Science@NASA
Comets are cosmic snowballs of frozen gases, rock, and dust that orbit the Sun When frozen, they are the size of a small town When a comet's orbit brings it close to the Sun, it heats up and spews dust and gases into a giant glowing head larger than most planets The dust and gases form a tail that stretches away from the Sun for millions of
- Comets 2025: See the Next Bright Comet in Autumn 2025 - Star Walk
The next comet to reach perihelion is C 2025 A6 (Lemmon), which should become easy to spot with binoculars from the Northern Hemisphere in late October We'll keep you updated on all the news about upcoming comets
- Comet | Definition, Composition, Facts | Britannica
comet, a small body orbiting the Sun with a substantial fraction of its composition made up of volatile ices When a comet comes close to the Sun, the ices sublimate (go directly from the solid to the gas phase) and form, along with entrained dust particles, a bright outflowing atmosphere around the comet nucleus known as a coma
- What Is a Comet? | NASA Space Place – NASA Science for Kids
A comet has two tails that get longer the closer it gets to the Sun Both tails are always directed away from the Sun The ion tail (blue) always points directly away from the Sun, while the dust tail (yellow) points away from the Sun in a slightly different direction than the ion tail
- Comets: Everything you need to know | Space
Comets are icy leftovers from the formation of the solar system Explore these 'dirty snowballs' in more detail with our ultimate comet guide
- Comet: Definition, Tails, Facts, Orbit, Visibility, Difference
Comet appearance varies from a bright fuzzy ball with a tail to a faint diffuse patch in the sky Distinctive comas and tails stretching millions of kilometers characterize many visible comets Comet visibility periods range from weeks to months depending on their orbits and activity levels
- Comet Information and the International Comet Quarterly (ICQ)
This is a key place to begin looking for useful and accurate information regarding news, observations, orbital data, designations and names, and good links regarding comets and related topics [sponsored by the International Comet Quarterly (ICQ)]
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