星球英文介绍

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.

1、mercury 水星

2、venus 金星

3、earth 地球

4、mars 火星

5、jupitor 木星

6、saturn 土星

7、Neptune 天王星

8、Uranus 海王星

扩展资料：

一是必须围绕恒星运转的天体；二是质量足够大，能依靠自身引力使天体呈圆球状；三是这个轨道附近应该没有其他物体。按这样的划分，太阳系的行星就只有水、金、地、火、木、土，加上天王、海王星这八颗。

与2006年之前提到的九大行星概念不同，在2006年8月24日于布拉格举行的第26届国际天文学联会中通过的第5号决议中，冥王星被划为矮行星，从太阳系九大行星中被除名。必须是围绕恒星运转的天体——冥王星相符。

质量足够大，能依靠自身引力使天体呈圆球状相符，但是冥王星没有能够清空其轨道上的其他物体，因此降级为矮行星。

参考资料来源：百度百科-八大行星

Mercury (水星): ——The Mercury is the smallest of the planets and the one nearest the sun, having a sidereal period of revolution about the sun of 88 days (水星是行星中最小且离太阳最近的星，围绕太阳公转所需的周期为88天。) Mars (火星): ——The Mars is the fourth planet from the sun, having a sidereal period of revolution about the sun of 687 days. (火星是距太阳距离居第四位的行星，绕太阳公转周期为687天，). Venus (金星): ——The Hesper is the planet Venus in its appearance. The Venus is the second planet from the sun, having a mass 0.815 times that of Earth, and a sidereal period of revolution about the sun of 224.7 days. When appearing as the evening star, it can be called Hesper/Hesperus. (金星是离太阳第二远的行星，它的质量是地球质量的0.815倍，绕太阳转的公转周期为224.7天。傍晚出现时称作长庚星) Saturn (土星): ——It is the sixth planet from the sun and the second largest in the solar system, having a sidereal period of revolution about the sun of 29.5 years and a mass 95 times that of Earth. (土星是距太阳第六远的行星，是太阳系中第二大行星，绕日公转周期29.5年，质量是地球的95倍。) Jupiter (木星): ——The Jupiter is the fifth planet from the sun, the largest and most massive in the solar system, having a sidereal period of revolution about the sun of 11.86 years. (木星是靠近太阳的第5颗行星，也是太阳系中最大的行星，绕太阳公转的恒星期为11.86年。) Uranus (天王星): ——The Uranus is the seventh planet from the sun, revolving about it every 84.07 years. (是离太阳第七近的行星，每绕太阳一周为84.07年。) Neptune (海王星): ——The Neptune is the eighth planet from the sun, having a sidereal period of revolution around the sun of 164.8 years.（是太阳的第八颗行星。围绕太阳公转的恒星周期为164.8年） Pluto (冥王星): ——The Pluto used to be the ninth planet in the solar system, but now it is listed as the Dwarf Planet. （冥王星曾经是太阳系的第九颗行星，但是现在被列为矮行星。）

mercury 水星venus 金星earth 地球mars 火星jupitor 木星saturn 土星Neptune 天王星Uranus 海王星pluto 冥王星九大行星按上面的顺序排列。实际现在是八大了。