Nine planets :: Cherry

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Cherry << Solar System | Top | Greece >> Nine planets Time:2004-04-24 Mercury Mercury orbits closer to the sun than any other planet, making it dry, hot, and virtually airless. although the planet's cratered surface resembles that of the moon, it is believed that the interior is actually similar to earth's, consisting primarily of iron and other heavy elements. this composite photograph was taken in 1974 by Mariner 10.the first probe to study Mercury in detail. Venus venus is the brightest object in our sky, after the sun and moon. swirling clouds of sulfur and sulfuric acid obscure Venus's surface and inhibited study of the planet from Earth until technology permitted space vehicles,outfitted with probes. to visit it. these probes determined that Venus is the hottst of the planets, with a surface temperature of about 460～ C ,(about 860～ F).scientists believe that a greenhouse effect causes the extreme temperature, hypothesizing that the planet's thick clouds and dense atmosphere trap energy from the sun Earth an oxygen-rich and protective atmosphere, moderate temperatures, abundant water, and a varied chemical compostition enable Earth to support life, the only planet known to harbor life, the planet is composed of rock and metal, which are present in molten form beneath its suface, the Apollo 17 spacecraft took this snapshot in 1972 of th Arabian Peninsula, the African continet, and Antarcitca(most of the white area near the bottom) Mars The most detailed information available about Mars has come from unpiloted spacecraft sent to the planet by the United States between 1964 and 1976.from this data, scientists have determined that the planet's atmosphere consists primarily of carbon dioxide, with small amounts of nitrogen, oxygen, water vapor, and other gases. because the atmosphere is extremely thin, daily temperatures can vary as much as 100 Celsius degrees(190 fahrenheit degrees), in general, surface temperature are too cold and surface pressures too low for water to exist in liquid state on Mars. the planet resembles a cold, high-altitude desert. Jupiter Jupiter is the largest of the planets with a volume more than 1,300 times greater than that of earth.Jupiter's colorful bands are cause by stron atmospheric currents and accentuated by a dense cloud cover. the massive planet, upper right, is shown here with its four largest satellites: Io, upper left, Ganymede, lower left, Europa, center, and callisto, lower right. Saturn Saturn, distinguished by its rings, is the the second largest planet in the solar system. This processed Hubble Space Telescope image shows the planet＊s cloud bands, storms, and rings as they would appear to the human eye. Uranus Uranus's blue-green color comes from the methane gas present in its cold, clear atmosphere, the dark shadings at the right edge of the sphere correspond to the day-night boundary on the planet, beyond this boundary, Uranus's northern hemisphere remains in a four-decade-long period of darkness because of the way the planet rotates. scientists compiled this view of Uranus from images returned from Voyager 2 in 1986 when the probe was 9.1 million km(5.7million mi) away from the planet. Neptune This image of Neptune, taken by the Voyager 2 spacecraft, shows the planet's most prominent features. the large dark oval surrounded by white clouds near the planet's equator is the great dark spot, as storm similar to Jupiter's great red spot, the smaller dark oval with a bright core below and to the right of the great dark spot is another storm known as dark spot 2. Pluto Pluto is farther from the Sun than the other planets in the solar system, although it occasionally moves in closer than Neptune due to an irregular orbit. The small, rocky, and cold planet takes 247.7 years to revolve around the Sun. This artist's rendition depicts Pluto, foreground; its moon, Charon, background; and the distant Sun, upper right. ^^ ** cherryoney Posted at 2004-04-24 14:52 Edit | Trackback(0) Comments Add Comment Updated