Olympus Mons a gigantic (about 600 km/375 mi in diameter) shield volcano on Mars, is larger across than the length of the Hawaiian Islands strung together. The Mars Pathfinder Mission of 1997 returned data that Martian volcanic rocks appear to be similar to those found on Earth, including some evidence of the rock andesite. The volcanism on the Earth's moon, Mars, Mercury, and Venus mostly occurred billions of years ago; these planetary bodies are now cold and dead. However, scientists have found evidence in Martian meteorites that indicates volcanic activity on Mars may have occurred as recent as 150 million years ago.
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Mars has the largest volcano in the solar system, Olympus Mons. It is 26 km (16 mi) high (almost twice as high as Earth |
发表于 2012-8-14 23:06:24
