|
In astrogeology, an arachnoid is a large structure of unknown origin, and they have been found only on the surface of the planet Venus. Arachnoids get their name from their resemblance to spider webs. They appear as concentric ovals surrounded by a complex network of fractures, and can span 200 kilometers. Over thirty arachnoids have been identified on Venus, so far. The arachnoid might be a strange relative to the volcano, but possibly different arachnoids are formed by different processes.〔This article contains text from the Astronomy Picture of the Day (). As a work of the United States Federal Government, it is in the public domain.〕 == See also == * Chaos terrain * Geysers on Mars * Pancake dome * Rille 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「Arachnoid (astrogeology)」の詳細全文を読む スポンサード リンク
|