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. 2026 May 9 [2]See Explanation. Clicking on the picture will download the highest resolution version available. Messier Craters in Stereo Image Credit: [3]Apollo 11, [4]NASA; Stereo Image Copyright [5]Patrick Vantuyne Explanation: Many bright nebulae and star clusters in planet Earth's sky are associated with the name of [6]astronomer Charles Messier from his famous 18th century catalog. His name is also given to these two large and remarkable craters on the Moon. [7]Standouts in the dark, smooth lunar Sea of Fertility or Mare Fecunditatis, Messier (left) and Messier A have dimensions of 15 by 8 and 16 by 11 kilometers respectively. Their elongated shapes are explained by the extremely shallow-angle trajectory followed by an impactor, moving left to right, that gouged out the craters. The shallow impact also resulted in two [8]bright rays of material extending along the surface to the right, beyond the picture. Intended to be viewed with [9]red/blue glasses (red for the left eye), this striking stereo picture of the crater pair was recently created from high resolution scans of two images ([10]AS11-42-6304, [11]AS11-42-6305) taken during the Apollo 11 mission to the Moon. Tomorrow's picture: moonset timelapse __________________________________________________________________ [12]< | [13]Archive | [14]Submissions | [15]Index | [16]Search | [17]Calendar | [18]RSS | [19]Education | [20]About APOD | [21]Discuss | [22]> __________________________________________________________________ Authors & editors: [23]Robert Nemiroff ([24]MTU) & [25]Jerry Bonnell ([26]UMCP) NASA Official: Amber Straughn [27]Specific rights apply. [28]NASA Web Privacy, [29]Accessibility, [30]Notices; A service of: [31]ASD at [32]NASA / [33]GSFC, [34]NASA Science Activation & [35]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2605/MessierCrater3d_vantuyne.jpg 3. http://nssdc.gsfc.nasa.gov/planetary/lunar/apollo11info.html 4. http://www.nasa.gov/ 5. https://apollojournals.org/alsj/ApAnPaVa.html 6. https://science.nasa.gov/people/explore-the-night-sky-hubbleatms-messier-catalog-bio/ 7. http://lroc.sese.asu.edu/posts/383 8. http://lunarnetworks.blogspot.com/2012/04/lroc-rays-of-messier.html 9. https://www.jpl.nasa.gov/edu/resources/project/roverview-3-d-glasses/ 10. http://www.lpi.usra.edu/resources/apollo/frame/?AS11-42-6304 11. http://www.lpi.usra.edu/resources/apollo/frame/?AS11-42-6305 12. https://apod.nasa.gov/apod/ap260508.html 13. https://apod.nasa.gov/apod/archivepix.html 14. https://apod.nasa.gov/apod/lib/apsubmit2015.html 15. https://apod.nasa.gov/apod/lib/aptree.html 16. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 17. https://apod.nasa.gov/apod/calendar/allyears.html 18. https://apod.com/feed.rss 19. https://apod.nasa.gov/apod/lib/edlinks.html 20. https://apod.nasa.gov/apod/lib/about_apod.html 21. https://asterisk.apod.com/discuss_apod.php?date=260509 22. https://apod.nasa.gov/apod/ap260510.html 23. http://www.phy.mtu.edu/faculty/Nemiroff.html 24. http://www.phy.mtu.edu/ 25. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 26. http://www.astro.umd.edu/ 27. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 28. https://www.nasa.gov/about/highlights/HP_Privacy.html 29. https://www.nasa.gov/general/accessibility/ 30. https://www.nasa.gov/privacy/ 31. https://astrophysics.gsfc.nasa.gov/ 32. https://www.nasa.gov/ 33. https://www.nasa.gov/centers/goddard/ 34. https://science.nasa.gov/learners 35. http://www.mtu.edu/