NASA 天文图片日历

探索宇宙的奇迹,每日一图

Ida和Dactyl:小行星和月球

(原标题: Ida and Dactyl: Asteroid and Moon)

2023-05-28

浏览次数: 14

这颗小行星有一颗卫星。1993年,机器人宇宙飞船伽利略号在前往木星的途中,在其漫长的星际航行中遇到并拍摄了两颗小行星。它拍摄到的第二颗小行星,243艾达,被意外地发现有一颗卫星。这颗名为Dactyl的小卫星直径只有约1.6公里,在这张锐化的特色图像的右侧,可以看到一个小点。相比之下,土豆形状的艾达要大得多,长约60公里,宽约25公里。Dactyl是迄今为止发现的第一颗小行星的卫星——现在已知许多小行星都有卫星。Ida和Dactyl这两个名字来自希腊神话。

查看原文解释

This asteroid has a moon. The robot spacecraft Galileo on route to Jupiter in 1993 encountered and photographed two asteroids during its long interplanetary voyage. The second minor planet it photographed, 243 Ida, was unexpectedly discovered to have a moon. The tiny moon, Dactyl, is only about 1.6 kilometers across and seen as a small dot on the right of the sharpened featured image. In contrast, the potato-shaped Ida is much larger, measuring about 60 kilometers long and 25 km wide. Dactyl is the first moon of an asteroid ever discovered -- now many asteroids are known to have moons. The names Ida and Dactyl are from Greek mythology.

最近天文图片