毅力号：如何着陆火星
Perseverance: How to Land on Mars
Image Credit: NASA, JPL, Mars 2020
Explanation: Slung beneath its rocket powered descent stage Perseverance hangs only a few meters above the martian surface, captured here moments before its February 18 touchdown on the Red Planet. The breath-taking view followed an intense seven minute trip from the top of the martian atmosphere. Part of a high resolution video, the picture was taken from the descent stage itself during the final skycrane landing maneuver. Three taut mechanical cables about 7 meters long are visible lowering Perseverance, along with an electrical umbilical connection feeding signals (like this image), to a computer on board the car-sized rover. Below Perseverance streamers of martian dust are kicked-up from the surface by the descent rocket engines. Immediately after touchdown, the cables were released allowing the descent stage to fly to a safe distance before exhausting its fuel as planned.
Tomorrow’s picture: the stars in a rose
毅力号：如何着陆火星
影像提供: NASA, JPL, Mars 2020
说明: 在这幅2月18日摄于着陆火星之前瞬间的影像里，毅力号悬垂在降落器火箭的下方，距离火星表面只有数公尺之遥。这幅令人屏息的俯视景观，为从火星大气顶端开始的激烈7分钟之旅画下句点。这张摄于降落器的影片定格，记录出动天空起动机着陆火星的最后阶段。影像里，3条长7公尺的绷紧机械索正在垂放毅力号，其旁的电气连接索，则把讯号（诸如这幅影像）传输到这部房车大小的火星车之电脑里。在毅力号下方，可见到降落器火箭引擎在火星表面扬起的尘缕。在毅力号着陆之后，这些索具立即断开，让降落器在耗尽燃料之前，能飞到安全的距离之外。
明日的图片: the stars in a rose
