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太阳系(solar system)水星 Mercury 金星 Venus 地球 Earth 火星 Mars 木星 Jupiter 土星 Saturn 天王星 Uranus 海王星 Neptune 冥王星 Pluto 符号(有图)：
企业工作号
1、水星(☿)、Mercury。
2、金星(♀)、Venus。
3、地球(⊕)、Earth。
4、火星(♂)、Mars。
5、木星(♃)、Jupiter。
6、土星(♄)、Saturn。
7、天王星(♅)、Uranus。
8、海王星(♆)、Neptune。
9、冥王星(♇)、Pluto。
扩展资料：
冥王星自1930年被发现以来，长期被列入太阳系九大行星之列。但是从2000年起，在太阳系边缘、海王星外侧的柯伊伯带中不断发现新天体，其个头越来越大，特别是2005年发现的阋神星，当时被认为比冥王星更大，因为当时估测的冥王星直径只有约2300公里。
近千年来，人们一直认为水星、金星、地球、火星、木星和土星是太阳系中的标准行星。19世纪后，天文学家陆续发现了天王星、海王星和冥王星，使太阳系的“行星”变成了9颗。此后，“九大行星”成为家喻户晓的说法。
自从80多年前被发现的那天起，冥王星便与“争议”二字联系在了一起。一是由于其发现的过程是基于一个错误的理论；二是由于当初将其质量估算错了，误将其纳入到了大行星的行列。不过，新的天文发现不断使“九大行星”的传统观念受到质疑。
天文学家先后发现冥王星与太阳系其他行星的一些不同之处。冥王星所处的轨道在海王星之外，属于太阳系外围的柯伊伯带，这个区域一直是太阳系小行星和彗星诞生的地方。
参考资料来源：百度百科-冥王星
参考资料来源：百度百科-太阳系八大行星
阳澄湖边
太阳系Solar Systemsolar system consists of the Sun and the other celestial objects gravitationally bound to it: the eight planets, their 165 known moons,[1] three dwarf planets (Ceres, Pluto, and Eris and their four known moons), and billions of small bodies. This last category includes asteroids, Kuiper belt objects, comets, meteoroids, and interplanetary dust.In broad terms, the charted regions of the Solar System consist of the Sun, four terrestrial inner planets, an asteroid belt composed of small rocky bodies, four gas giant outer planets, and a second belt, called the Kuiper belt, composed of icy objects. Beyond the Kuiper belt lies the scattered disc, the heliopause, and ultimately the hypothetical Oort cloud.In order of their distances from the Sun, the planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Six of the eight planets are in turn orbited by natural satellites, usually termed "moons" after Earth's Moon, and each of the outer planets is encircled by planetary rings of dust and other particles. All the planets except Earth are named after gods and goddesses from Greco-Roman mythology. The three dwarf planets are Pluto, the largest known Kuiper belt object; Ceres, the largest object in the asteroid belt; and Eris, which lies in the scattered disc.Jupiter Jupiter (5.2 AU), at 318 Earth masses, masses 2.5 times all the other planets put together. It is composed largely of hydrogen and helium. Jupiter's strong internal heat creates a number of semi-permanent features in its atmosphere, such as cloud bands and the Great Red Spot. Jupiter has sixty-three known satellites. The four largest, Ganymede, Callisto, Io, and Europa, show similarities to the terrestrial planets, such as volcanism and internal heating.[51] Ganymede, the largest satellite in the Solar System, is larger than Mercury.Saturn Saturn (9.5 AU), famous for its extensive ring system, has similarities to Jupiter, such as its atmospheric composition. Saturn is far less massive, being only 95 Earth masses. Saturn has sixty known satellites (and 3 unconfirmed); two of which, Titan and Enceladus, show signs of geological activity, though they are largely made of ice.[52] Titan is larger than Mercury and the only satellite in the Solar System with a substantial atmosphere.Uranus Uranus (19.6 AU), at 14 Earth masses, is the lightest of the outer planets. Uniquely among the planets, it orbits the Sun on its side; its axial tilt is over ninety degrees to the ecliptic. It has a much colder core than the other gas giants, and radiates very little heat into space.[53] Uranus has twenty-seven known satellites, the largest ones being Titania, Oberon, Umbriel, Ariel and Miranda.Mercury Mercury (0.4 AU) is the closest planet to the Sun and the smallest planet (0.055 Earth masses). Mercury has no natural satellites, and its only known geological features besides impact craters are "wrinkle-ridges", probably produced by a period of contraction early in its history.[36] Mercury's almost negligible atmosphere consists of atoms blasted off its surface by the solar wind.[37] Its relatively large iron core and thin mantle have not yet been adequately explained. Hypotheses include that its outer layers were stripped off by a giant impact, and that it was prevented from fully accreting by the young Sun's energy.[38][39]Venus Venus (0.7 AU) is close in size to Earth (0.815 Earth masses) and, like Earth, has a thick silicate mantle around an iron core, a substantial atmosphere and evidence of internal geological activity. However, it is much drier than Earth and its atmosphere is ninety times as dense. Venus has no natural satellites. It is the hottest planet, with surface temperatures over 400 °C, most likely due to the amount of greenhouse gases in the atmosphere.[40] No definitive evidence of current geological activity has been detected on Venus, but it has no magnetic field that would prevent depletion of its substantial atmosphere, which suggests that its atmosphere is regularly replenished by volcanic eruptions.[41]Earth Earth (1 AU) is the largest and densest of the inner planets, the only one known to have current geological activity, and the only planet known to have life. Its liquid hydrosphere is unique among the terrestrial planets, and it is also the only planet where plate tectonics has been observed. Earth's atmosphere is radically different from those of the other planets, having been altered by the presence of life to contain 21% free oxygen.[42] It has one satellite, the Moon, the only large satellite of a terrestrial planet in the Solar System.Mars Mars (1.5 AU) is smaller than Earth and Venus (0.107 Earth masses). It possesses a tenuous atmosphere of mostly carbon dioxide. Its surface, peppered with vast volcanoes such as Olympus Mons and rift valleys such as Valles Marineris, shows geological activity that may have persisted until very recently.[43] Mars has two tiny natural satellites (Deimos and Phobos) thought to be captured asteroids.[44] 我听说英文的维基百科已经可以在中国使用了，所以你直接去wikipedia查就可以了。 Neptune Neptune (30 AU), though slightly smaller than Uranus, is more massive (equivalent to 17 Earths) and therefore denser. It radiates more internal heat, but not as much as Jupiter or Saturn.[54] Neptune has thirteen known satellites. The largest, Triton, is geologically active, with geysers of liquid nitrogen.[55] Triton is the only large satellite with a retrograde orbit. Neptune is accompanied in its orbit by a number of minor planets in a 1:1 resonance with it, termed Neptune Trojans.
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