火星的平顶岩丘

2023年5月2日

Flat Rock Hills on Mars
Image Credit & Copyright: NASA, JPL-Caltech, MSSS; Processing: Neville Thompson

Explanation: Why are there so many flat rocks on Mars? Some views of plains and hills on Mars show many rocks that are unusually flat when compared to rocks on Earth. One reason for this is a process that is common to both Mars and Earth: erosion. The carbon-dioxide wind on Mars can act like sandpaper when it blows around gritty Martian sand. This sand can create differential erosion, smoothing over some rocks, while wearing down the tops of other long-exposed stones. The featured image capturing several hills covered with flat-topped rocks was taken last month by NASA’s Curiosity Rover on Mars. This robotic rover has now been rolling across Mars for ten years and has helped uncover many details of the wet and windy past of Earth’s planetary neighbor. After taking this and other images, Curiosity carefully navigated stones and slippery sand to climb up Marker Band Valley.

Tomorrow’s picture: black hole galaxy

火星的平顶岩丘
影像提供与版权: NASA, JPL-Caltech, MSSS; 影像处理: Neville Thompson

说明: 为何火星有这么多平顶的岩石？相对于地球上的岩石，火星的一些平原和丘陵看似拥有许多格外平坦的石块。造成这种景观的原因之一，是火星和地球都共有的侵蚀作用过程。以二氧化碳为主体的火星风所挟带的火星沙砾，发挥了像砂纸一样的作用，而这些沙砾可造成差异侵蚀，让部分岩石变得光滑，也磨平了其他长期暴露岩块的顶部。这幅由美国国家航空航天局好奇号火星车摄于上个月的主题影像，就记录了数座覆着平顶岩的山丘。这部火星车已经在火星表面漫游了10年，并为厘清地球这颗行星近邻的潮湿和多风的历史细节提供了许多助力。在拍下这幅及其他影像之后，好奇号小心翼翼的绕过岩块和滑溜的沙地，然后爬上了标志环谷（Marker Band Valley）。

明日的图片: black hole galaxy