DART：撞击小行星双卫一

2022年9月27日

DART: Impact on Asteroid Dimorphos
Video Credit: NASA, JHUAPL, DART

Explanation: Could humanity deflect an asteroid headed for Earth? Yes. Deadly impacts from large asteroids have happened before in Earth’s past, sometimes causing mass extinctions of life. To help protect our Earth from some potential future impacts, NASA tested a new planetary defense mechanism yesterday by crashing the robotic Double Asteroid Redirection Test (DART) spacecraft into Dimorphos, a small asteroid spanning about 170-meters across. As shown in the featured video, the impact was a success. Ideally, if impacted early enough, even the kick from a small spacecraft can deflect a large asteroid enough to miss the Earth. In the video, DART is seen in a time-lapse video first passing larger Didymos, on the left, and then approaching the smaller Dimorphos. Although the video ends abruptly with DART’s crash, observations monitoring the changed orbit of Dimorphos — from spacecraft and telescopes around the world — have just begun.

Tomorrow’s picture: furious sky

DART：撞击小行星双卫一
影片提供: NASA, JHUAPL, DART

说明: 人类能否能让直冲地球而来的小行星改道呢？能的。地球过去发生过毁灭性的大型小行星撞击，有时更造成生物大灭绝。为了防止我们的地球未来再受到这类大撞击，NASA测试了一种新的行星防御机制，将无人驾驶的双小行星改道测试 (DART) 航天器，撞向了宽约170公尺的小型小行星双卫一（Dimorphos 迪摩佛斯）。如主题影片所示，这次的撞击颇为成功。理想情况下，如果撞击施行得够早，即使是用小航天器撞击，也能让使大型小行星偏移到足以错过地球。在影片里中，在一段缩时影片里，可以看到DART先掠过左侧较大的双生星（Didymos），然后再靠近较小的双卫一。尽管影片在DART撞击后突然结束，但世界各地的太空船和望远镜，监测双卫一的轨道会如何改变的工作才刚要开始。

明日的图片: furious sky