planet(redirected from planetologists)
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a. In the traditional model of solar systems, a celestial body larger than an asteroid or comet, illuminated by light from a star, such as the sun, around which it revolves.
b. A celestial body that orbits the sun, has sufficient mass to assume nearly a round shape, clears out dust and debris from the neighborhood around its orbit, and is not a satellite of another planet.
2. One of the seven celestial bodies, Mercury, Venus, the moon, the sun, Mars, Jupiter, and Saturn, visible to the naked eye and thought by ancient astronomers to revolve in the heavens about a fixed Earth and among fixed stars.
a. The collection of life forms supported on Earth: an asteroid that threatened the whole planet.
b. People as a whole; humankind or the general public: The entire planet was affected by the global recession.
4. One of the seven revolving astrological celestial bodies that in conjunction with the stars are believed to influence human affairs and personalities.
[Middle English, from Old French planete, from Late Latin planēta, from Greek planētēs, variant of planēs, planēt-, from planāsthai, to wander; see pelə- in Indo-European roots.]
Usage Note: Clyde Tombaugh's discovery of Pluto in 1930 added a ninth planet to our solar system, and thereafter students of astronomy were taught the familiar list of nine planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto. But in 2006, the International Astronomical Union (IAU) voted to change the definition of planet, requiring that a celestial body must have enough mass to assume a round shape and "clear the neighborhood around its orbit" in order to qualify as a planet. This means that a planet cannot have other objects in or crossing its orbit except smaller objects that have been captured by its gravity, such as those that revolve around it as moons. Because Neptune's large mass has captured Pluto so that the two planets remain in orbits that cross, Pluto has not cleared its own orbit and was therefore demoted from planet status to that of a newly created category, dwarf planet. Like a planet, a dwarf planet orbits the sun, is large enough to assume a nearly round shape, and does not orbit a planet (as our Moon does). But a dwarf planet does not clear the neighborhood around its orbit and may cross the paths of other objects orbiting the sun. Other dwarf planets include Ceres, whose orbit is in the asteroid belt between Mars and Jupiter, and Eris, an object in the Kuiper belt beyond Pluto. At the same meeting, the IAU created a third category of objects known as small solar system bodies, which includes asteroids (sometimes referred to as "minor planets," compounding the difficulty of the term planet), comets, objects beyond Neptune's orbit, and other nonspherical bodies. Although officially approved, this new scheme of the solar system remains controversial among astronomers and may well be revised.
1. (Celestial Objects) Also called: major planet any of the eight celestial bodies, Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, that revolve around the sun in elliptical orbits and are illuminated by light from the sun
2. (Celestial Objects) Also called: extrasolar planet any other celestial body revolving around a star, illuminated by light from that star
3. (Astrology) astrology any of the planets of the solar system, excluding the earth but including the sun and moon, each thought to rule one or sometimes two signs of the zodiac. See also house9
[C12: via Old French from Late Latin planēta, from Greek planētēs wanderer, from planaein to wander]
a. any of the nine large heavenly bodies revolving about the sun and shining by reflected light: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, or Pluto in the order of their proximity to the sun.
b. a similar body revolving about a star other than the sun.
c. (formerly) a moving celestial body, as distinguished from a fixed star, applied also to the sun and moon.
2. Astrol. any celestial body regarded as exerting an influence on human affairs.
3. (often cap.) the planet Earth considered as a single ecosystem.
[1250–1300; Middle English planete (< Old French planète) < Late Latin planētae < Greek (astéres) planḗtai literally, wandering (stars)]
A celestial body that does not produce its own light, is larger than an asteroid, and is illuminated by light from a star, such as the sun, around which it revolves. In our solar system there are eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Pluto was considered a planet until 2006, when it was reclassified as a dwarf planet.
Word History To learn the origins of the names of the planets is to have a little lesson in Roman mythology. Mercury moves fastest through the sky and was named after the swift-footed messenger of the gods, Mercury. Venus, the morning and evening star, was named after the Roman goddess of love because of its beauty and the pure brightness of its light. The reddish appearance of Mars reminded early astronomers of the color of blood, so Mars was named after the Roman god of war. Jupiter is the largest of the planets and was named after the king of the gods. Jupiter's father was Saturn, the name given to the next planet after Jupiter. To continue that logic, the name of Saturn's own father, Uranus, was given to the next planet after Saturn. Viewed through a telescope, the planet Neptune appears sea-green, and it gets its name from the Roman god of the sea. Finally, the darkest reaches of the solar system are the home of the frozen object Pluto, traditionally considered a planet, and named after the god of the cold world of the dead, the underworld.
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|Noun||1.||planet - (astronomy) any of the nine large celestial bodies in the solar system that revolve around the sun and shine by reflected light; Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune, and Pluto in order of their proximity to the sun; viewed from the constellation Hercules, all the planets rotate around the sun in a counterclockwise direction|
astronomy, uranology - the branch of physics that studies celestial bodies and the universe as a whole
biosphere - the regions of the surface and atmosphere of the Earth (or other planet) where living organisms exist
inferior planet - any of the planets whose orbit lies inside the earth's orbit
gas giant, Jovian planet - any of the four outermost planets in the solar system; much larger than Earth and gaseous in nature (like Jupiter)
daystar, morning star, Phosphorus, Lucifer - a planet (usually Venus) seen just before sunrise in the eastern sky
outer planet - (astronomy) a major planet whose orbit is outside the asteroid belt (Jupiter, Saturn, Uranus, Neptune, Pluto)
solar system - the sun with the celestial bodies that revolve around it in its gravitational field
superior planet - any of the planets whose orbit lies outside the earth's orbit
terrestrial planet - a planet having a compact rocky surface like the Earth's; the four innermost planets in the solar system
|2.||planet - a person who follows or serves another|
follower - a person who accepts the leadership of another
|3.||planet - any celestial body (other than comets or satellites) that revolves around a star|
PlanetsEarth, Jupiter, Mars, Mercury, Neptune, Pluto, Saturn, Uranus, Venus
n → Planet m
planet[ˈplænɪt] n → pianeta m
any of the bodies (eg the Earth) which move round the Sun or round another star. Mars and Jupiter are planets, but the Moon is not. planeet كوكَب سَيّار планета planeta planeta der Planet planet πλανήτηςplaneta planeet سیاره planeetta planète כּוֹכָב לֶכֶת ग्रह planet bolygó planet pláneta, reikistjarna pianeta 惑星 행성 planeta planēta planet planeetplanetplaneta سياره planeta planetă планета planéta planet planeta planet ดาวนพเคราะห์ gezegen 行星 планета سيارہ، جرم فلکي hành tinh 行星ˈplanetary adjective
planetêr كَوْكَبي، سَيّاري планетен planetário planetární planetarisch planetarisk; planet- πλανητικόςplanetario planetaar- وابسته به سیاره planetaarinen planétaire שֶׁל כּוֹכבי לֶכֶת ग्रहीय planetarni bolygó- planetarium reikistjörnu- planetario 惑星の 행성의 planetinis, planetų planētas-; planētu- planet planetairplanet-, planetarisk planetarny سياره ته مربوط planetário planetar планетный;планетарный planetárny planeten planetarni planetarisk, planet- แห่งดาวนพเคราะห์ gezegenle ilgili 行星的 планетний; планетарний سياروں سے متعلق thuộc về hành tinh 行星的