水星Ｍercury 20 marks @ bxzbthf的部落格

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水星Ｍercury 20 marks

發問:

水星Ｍercury English information please.( +chinese) It's okay if you don't write the chinese version. It's better f you wrote the chinese version. Thanks!

最佳解答:

Mercury is the inner most and smallest planet in the solar system, orbiting the Sun once every 88 days. Mercury is bright when viewed from Earth, ranging from ?2.0 to 5.5 in apparent magnitude, but is not easily seen as its greatest angular separation from the Sun is only 28.3°. It can only be seen in morning or evening twilight. 水星是太陽系最內側與最小的行星，比月球大1/3；也是太陽系中運動最快的行星，環繞太陽一周只要88天。由地球上看水星的視星等亮度在-2.0至5.5等之間，但是因為距離太陽的最大角度（最大距角）只有28.3°：淹沒在日出前或日落後的暮曙光中，因此不太容易被看見。 Mercury is one of four terrestrial planets in the solar system, and is a rocky body like the Earth. It is the smallest planet in the solar system, with an equatorial radius of 2439.7 km. Mercury is even smaller—albeit more massive—than the largest natural satellites in the solar system, Ganymede and Titan. Mercury consists of approximately 70% metallic and 30% silicate material. Mercury's density is the second highest in the Solar System at 5.427 g/cm3, only slightly less than Earth’s density of 5.515 g/cm3.[3] If the effect of gravitational compression were to be factored out, the materials of which Mercury is made would be denser, with an uncompressed density of 5.3 g/cm3 versus Earth’s 4.4 g/cm3. 水星是與地球相似的4顆類地行星之一，並且是4顆中最小的，在赤道的直徑是4,879 公里。水星甚至比一些巨大的衛星，像是加利美德和泰坦，還要小（雖然質量較大）。水星的總質量約為30,000兆公噸，只有地球的5.5%。核的周围是 600km 厚的行星幔。水星的70%是金屬，30%是矽酸鹽物質，5.43 g/cm3的密度上是太陽系的行星中第二大的，只有地球的密度比它大（水的密度是1.00 g/ cm3）。如果不考慮重力壓縮對物質密度的影響，水星物質的密度將是最高的。未經重力壓縮的水星物質密度是5.3 g/cm3，相較之下的地球物質只有4.4 g/cm3 。 2008-10-28 22:19:54 補充： Mercury's density can be used to infer details of its inner structure. While the Earth’s high density results appreciably from gravitational compression, particularly at the core, Mercury is much smaller and its inner regions are not nearly as strongly compressed. 2008-10-28 22:20:01 補充： Therefore, for it to have such a high density, its core must be large and rich in iron.Geologists estimate that Mercury’s core occupies about 42% of its volume; for Earth this proportion is 17%. Recent research strongly suggests Mercury has a molten core. 2008-10-28 22:20:18 補充：水星的高密度可以推測其內部結構的細節。地球的高密度是，特別是核心，由重力壓縮所導致的。水星是如此的小，因此它的內部不會被強力的擠壓，所以它要有如此高的密度，它的核心必然是大且富含鐵的[8]。地質學家估計水星的核心佔有體積的42%（地球的核心只佔體積的17%），最近的研究強烈建議水星有一個熔融的核心。 2008-10-28 22:24:56 補充： Surrounding the core is a 600 km mantle consisted of silicates. It is generally thought that early in Mercury's history 環繞核心的是厚600nbsp;公里的地函，一般認為是在水星早期的歷史上就形成 2008-10-28 22:25:54 補充： a giant impact with a body several hundred kilometers across stripped the planet of much of its original mantle material, resulting in the relatively thin mantle compared to the sizable core. 一次直徑達數百公里的巨大物體的撞擊，剝離了行星原來的地涵物質，造成地涵相對於核心的尺寸是很薄的一層 2008-10-28 22:26:31 補充： Atmosphere Surface pressure: trace Composition 42% Molecular oxygen 29.0% sodium 22.0% hydrogen 6.0% helium 0.5% potassium Trace amounts of argon, nitrogen, carbon dioxide, water vapor, xenon, krypton, & neon 大氣表面壓力：微量大氣組成： 31.7% 鉀 24.9% 鈉 9.5% 氧原子 7.0% 氬 5.9% 氦 5.6% 氧分子 5.2% 氮 3.6% 二氧化碳 3.4% 水 3.2% 氫 2008-10-28 22:28:21 補充：赤度半徑 2439.7公里自轉需時 58.6462地球天公轉需時 87.969地球天行星公轉速度每秒47.88公里表面平均溫度 179℃ 日間最高溫度 427℃ 夜間最低溫度零下173℃ 衛星數目 0 平均距離太陽(萬公里) 57.09 平均密度 5.42gm/cm

其他解答:

Mercury is the innermost and smallest planet in the solar system, orbiting the Sun once every 88 days. Mercury is bright when viewed from Earth, ranging from ?2.0 to 5.5 in apparent magnitude, but is not easily seen as its greatest angular separation from the Sun is only 28.3°. It can only be seen in morning or evening twilight. Comparatively little is known about it; the first of two spacecraft to visit Mercury was Mariner 10, which mapped only about 45% of the planet’s surface from 1974 to 1975. The second is the MESSENGER spacecraft, which mapped another 30% during its flyby of January 14, 2008. MESSENGER will make one more pass by Mercury in 2009, followed by orbital insertion in 2011, and will then survey and map the entire planet.