A comet has four components: a nucleus, a coma, a dust tail and an ion tail. Define comet. A comet is a ball of mostly ice that moves around in outer space.Comets are often described as "dirty snowballs". The dust in the coma is not affected by magnetic fields but is vaporized by the Sun's heat, and forms a curved tail which follows the comet's orbit. The gas tail is created by the solar wind, pushing gas away from the comet's coma and pointing straight back from the Sun. It is sometimes described as a “dirty snowball.” There are billions of comets in the solar system , but most never pass close by Earth. A comet is a big ball of particles, including rocks, ice and dust. Il est constitué de glaces et de poussières. All English simple definitions from our dictionary Search comet and thousands of other words in English Cobuild dictionary from Reverso. The nucleus of a comet contains the vast majority of its total mass. The halo is known as the comets coma. What happens is the solar radiation vaporizes the ice and gas gas in the comet into a halo around it. The best-known comet is called Halley’s Comet. A comet is a small, icy object that orbits the sun and has a long "tail" of gas. The comet gained notoriety beyond the astronomical community when a California religious cult thought the comet was a spacecraft that was arriving to rescue them. Comets are found traveling throughout space. At first glance, asteroids may seem like run-of-the-mill space rocks, but these ancient solar system remnants come in all shapes, sizes and flavors. Some comets can be seen from Earth every few years, while others pass by once in a person's lifetime. A comet is a small chunk of dust and ice that orbits, or travels around, the sun . A comet is an icy, small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process called outgassing.This produces a visible atmosphere or coma, and sometimes also a tail.These phenomena are due to the effects of solar radiation and the solar wind acting upon the nucleus of the comet. Comets have a halo when they move close to the Sun. comet: A celestial body, observed only in that part of its orbit that is relatively close to the sun, having a head consisting of a solid nucleus surrounded by a nebulous coma up to 2.4 million kilometers (1.5 million miles) in diameter and an elongated curved vapor tail arising from the coma when sufficiently close to the sun. A celestial phenomenon with the appearance given by the orbiting celestial body. It can be seen from Earth about every 76 years. comet synonyms, comet pronunciation, comet translation, English dictionary definition of comet. They are very different from asteroids.The orbital inclinations of comets are usually high and not near the ecliptic where most solar system objects are found. This big ball containing most of the material is called a nucleus . comet (plural comets) A celestial body consisting mainly of ice, dust and gas in a (usually very eccentric) orbit around the Sun and having a "tail" of matter blown back from it by the solar wind as it approaches the Sun. Une comète est un corps à peu près sphérique qui peut atteindre une dizaine de kilomètres de diamètre. Asteroids. Comet Hale-Bobb: Named after the two astronomers that discovered it, Alan Hale and Thomas Bopp, the comet’s orbit is 2,300 years. Outer space.Comets are often described as `` dirty snowballs '' vaporizes the ice and gas gas in the comet a. Travels around, the sun and has a long `` tail '' of gas of a comet the... With the appearance given by the orbiting celestial body from Reverso move close to the sun comet! 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