米馬斯有大環形山的小月亮
Mimas: Small Moon with a Big Crater
發表日期:2025-01-12
撞擊米馬斯的東西幾乎摧毀了它。 現在留下的是土星最小的圓形衛星上最大的撞擊坑之一。 分析表明,如果撞擊力稍大一些,就會完全摧毀米馬斯。 這個巨大的隕石坑以 1789 年發現米馬斯的威廉-赫歇爾爵士的名字命名為 "赫歇爾"(Herschel),它橫跨約 130 公里,這裡就是它的特徵。米馬斯質量較小,其表面引力剛夠形成一個球形天體,但又很弱,足以形成如此大的表面特徵。米馬斯主要由水冰和少量岩石組成--因此用 "骯髒的大雪球 "來形容它再合適不過了。這張圖片是 2010 年卡西尼號機器人飛船在環繞土星的軌道上飛越米馬斯時拍攝的。 互動:穿越米馬斯 1 月 14 日:紐約業餘天文學家協會主辦的 Zoom APOD 講座
原文:Whatever hit Mimas nearly destroyed it. What remains is one of the largest impact craters on one of Saturn's smallest round moons. Analysis indicates that a slightly larger impact would have destroyed Mimas entirely. The huge crater, named Herschel after the 1789 discoverer of Mimas, Sir William Herschel, spans about 130 kilometers and is featured here. Mimas' low mass produces a surface gravity just strong enough to create a spherical body but weak enough to allow such relatively large surface features. Mimas is made of mostly water ice with a smattering of rock - so it is accurately described as a big dirty snowball. The featured image was taken during the closest-ever flyby of the robot spacecraft Cassini past Mimas in 2010 while in orbit around Saturn. Interactive: Take a trek across Mimas January 14: Zoom APOD Lecture hosted by the Amateur Astronomers of Association of New York
※ 本文由萌芽機器人自動轉貼自每日一天文圖(Astronomy Picture of the Day,APOD),原文為英文,正體中文是透過 DeepL 翻譯及 OpenCC 進行自動處理,內容僅供參考,若有任何錯誤之處還請見諒!
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