火星上的洞

2020 March 1

A Hole in Mars
Image Credit: NASA, JPL, U. Arizona

Explanation: What created this unusual hole in Mars? The hole was discovered by chance in 2011 on images of the dusty slopes of Mars’ Pavonis Mons volcano taken by the HiRISE instrument aboard the robotic Mars Reconnaissance Orbiter currently circling Mars. The hole, shown in representative color, appears to be an opening to an underground cavern, partly illuminated on the image right. Analysis of this and follow-up images revealed the opening to be about 35 meters across, while the interior shadow angle indicates that the underlying cavern is roughly 20 meters deep. Why there is a circular crater surrounding this hole remains a topic of speculation, as is the full extent of the underlying cavern. Holes such as this are of particular interest because their interior caves are relatively protected from the harsh surface of Mars, making them relatively good candidates to contain Martian life. These pits are therefore prime targets for possible future spacecraft, robots, and even human interplanetary explorers.

Tomorrow’s picture: big dolphin

火星上的洞
图片版权：NASA，JPL，U. Arizona

说明：是什么创造了火星上这些不寻常的洞？2011年，在一张火星帕弗尼斯火山尘土飞扬的斜坡的照片上，偶然发现了这个洞。这张照片是火星勘测轨道飞行器上的HiRISE设备所拍摄的，该飞行器目前仍在绕火星运行。这个洞似乎是地下洞穴的一个入口，如图中深颜色部分所示，图中洞的右侧被部分照亮。通过分析这系列图片得知，这个洞的入口直径大概35米，而内部阴影角度显示，下部的洞穴深约20米。为什么会有围绕着这个洞的圆形撞击坑，以及洞下面整个范围的情况，仍然还只能推测。这种类型的洞之所以特别引人注意，是因为它们能给火星上的生命提供一定保护，使其免遭火星表面恶劣环境的威胁，它们也是相对适宜火星生命生存的候选地。这些坑也因此成为未来可能的星际探测器，机器人，甚至人类行星际探索的首要探索目标。

明日图片：big dolphin