| 翻訳と辞書 |
| Jeans (Martian crater) ： ウィキペディア英語版 |
Jeans (Martian crater)
Jeans Crater is an impact crater in the Mare Australe quadrangle of Mars, located at 69.8°S latitude and 205.9°W longitude. It is 80.2 km in diameter and was named after James Hopwood Jeans, and the name was approved in 1973 by the International Astronomical Union (IAU) Working Group for Planetary System Nomenclature (WGPSN). The pictures below show dark areas in which frost is disappearing and the dark ground beneath is being exposed.〔http://www.jpl.nasa.gov/news/news.php?release=2013-034〕 Layers are also visible—probably from the many cycles of mantle deposition.
Wikijeans.jpg|Jeans (Martian crater), as seen by CTX camera (on Mars Reconnaissance Orbiter).
Wikijeanslayersspots.jpg|Jeans crater showing layers and dark spots from frost disappearing, as seen by CTX camera (on Mars Reconnaissance Orbiter). Note: this is an enlargement of the previous image of Jeans crater.
==Why craters are important==
The density of impact craters is used to determine the surface ages of Mars and other solar system bodies.〔http://www.lpi.usra.edu/publications/slidesets/stones/〕 The older the surface, the more craters present. Crater shapes can reveal the presence of ground ice.
抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』
■ウィキペディアで「Jeans (Martian crater)」の詳細全文を読む
スポンサード リンク
| 翻訳と辞書 : 翻訳のためのインターネットリソース |
Copyright(C) kotoba.ne.jp 1997-2016. All Rights Reserved.
|
|