Astronomy Picture of the Day [1]Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2023 May 2 [2]A view of Mars from the Curiosity rover on Mars is pictured in black and white. Many rocks and hills are visible, with a hill containing many unusually flat rocks visible on the right. Please see the explanation for more detailed information. Flat Rock Hills on Mars Image Credit & Copyright: [3]NASA, [4]JPL-Caltech, [5]MSSS; Processing: [6]Neville Thompson Explanation: Why are there so many flat rocks on Mars? Some views of plains and hills on [7]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: [8]erosion. The [9]carbon-dioxide [10]wind on Mars can act like sandpaper when it blows around gritty [11]Martian sand. This sand can create differential erosion, smoothing over [12]some rocks, while wearing down the tops of other long-exposed stones. The [13]featured image capturing [14]several hills covered with flat-topped rocks was taken last month by NASA's [15]Curiosity Rover on Mars. This robotic rover has now been rolling across Mars for ten years and has helped [16]uncover many details of the wet and [17]windy past of Earth's planetary neighbor. After taking this and [18]other images, Curiosity carefully navigated stones and slippery sand to climb up [19]Marker Band Valley. Tomorrow's picture: black hole galaxy __________________________________________________________________ [20]< | [21]Archive | [22]Submissions | [23]Index | [24]Search | [25]Calendar | [26]RSS | [27]Education | [28]About APOD | [29]Discuss | [30]> __________________________________________________________________ Authors & editors: [31]Robert Nemiroff ([32]MTU) & [33]Jerry Bonnell ([34]UMCP) NASA Official: Phillip Newman [35]Specific rights apply. [36]NASA Web Privacy Policy and Important Notices A service of: [37]ASD at [38]NASA / [39]GSFC, [40]NASA Science Activation & [41]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2305/FlatMars_CuriosityThompson_2713.jpg 3. https://www.nasa.gov/ 4. https://www.jpl.nasa.gov/ 5. https://www.msss.com/ 6. https://www.flickr.com/people/nev-t/ 7. https://solarsystem.nasa.gov/planets/mars/in-depth/ 8. https://en.wikipedia.org/wiki/Erosion 9. https://solarsystem.nasa.gov/planets/mars/in-depth/#otp_atmosphere 10. https://apod.nasa.gov/apod/ap150303.html 11. https://apod.nasa.gov/apod/ap190924.html 12. https://geology.com/stories/13/rocks-on-mars/ 13. https://www.flickr.com/photos/nev-t/52814100597/in/pool-apods/ 14. https://mars.nasa.gov/resources/27373/n_r000_3783_edr100cylasb2208_autolm1/ 15. https://mars.nasa.gov/msl/home/ 16. https://mars.nasa.gov/msl/mission/science/results/ 17. https://apod.nasa.gov/apod/ap011017.html 18. https://mars.nasa.gov/resources/27294/curiositys-360-degree-view-of-marker-band-valley/ 19. https://mars.nasa.gov/msl/mission-updates/?month=4&year=2023 20. https://apod.nasa.gov/apod/ap230501.html 21. https://apod.nasa.gov/apod/archivepix.html 22. https://apod.nasa.gov/apod/lib/apsubmit2015.html 23. https://apod.nasa.gov/apod/lib/aptree.html 24. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 25. https://apod.nasa.gov/apod/calendar/allyears.html 26. https://apod.nasa.gov/apod.rss 27. https://apod.nasa.gov/apod/lib/edlinks.html 28. https://apod.nasa.gov/apod/lib/about_apod.html 29. https://asterisk.apod.com/discuss_apod.php?date=230502 30. https://apod.nasa.gov/apod/ap230503.html 31. http://www.phy.mtu.edu/faculty/Nemiroff.html 32. http://www.phy.mtu.edu/ 33. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 34. http://www.astro.umd.edu/ 35. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 36. https://www.nasa.gov/about/highlights/HP_Privacy.html 37. https://astrophysics.gsfc.nasa.gov/ 38. https://www.nasa.gov/ 39. https://www.nasa.gov/centers/goddard/ 40. https://science.nasa.gov/learners 41. http://www.mtu.edu/