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 June 6 [2]See Explanation. Clicking on the picture will download the highest resolution version available. Charon: Moon of Pluto Image Credit: [3]NASA, [4]Johns Hopkins Univ./APL, [5]Southwest Research Institute, [6]U.S. Naval Observatory Explanation: A darkened and mysterious north polar region [7]known to some as Mordor Macula caps this premier view [8]of Charon, Pluto's largest moon. The high-resolution image was captured by the [9]interplanetary space probe [10]New Horizons near its closest approach to distant Pluto on July 14, 2015. [11]The combined blue, red, and infrared image data was processed to enhance colors and follow variations in Charon's surface properties with a resolution of about 2.9 kilometers (1.8 miles). A stunning image of Charon's Pluto-facing hemisphere, it also features a clear view of an apparently moon-girdling belt of fractures and canyons that seems to separate smooth southern plains from varied northern terrain. Charon is 1,214 kilometers (754 miles) across. That's about 1/10th the size of planet Earth but a whopping 1/2 the diameter of [12]Pluto itself, and makes it the largest satellite relative to its parent body in the Solar System. Still, the moon appears as a small bump at about the 1 o'clock position on Pluto's disk in the grainy, negative, telescopic picture inset at upper left. That image was used by James Christy and Robert Harrington at the U.S. Naval Observatory in Flagstaff to [13]discover Charon in June of 1978. Tomorrow's picture: Jupiter and Venus from Earth __________________________________________________________________ [14]< | [15]Archive | [16]Submissions | [17]Index | [18]Search | [19]Calendar | [20]RSS | [21]Education | [22]About APOD | [23]Discuss | [24]> __________________________________________________________________ Authors & editors: [25]Robert Nemiroff ([26]MTU) & [27]Jerry Bonnell ([28]UMCP) NASA Official: Amber Straughn [29]Specific rights apply. [30]NASA Web Privacy, [31]Accessibility, [32]Notices; A service of: [33]ASD at [34]NASA / [35]GSFC, [36]NASA Science Activation & [37]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2606/Charon-Neutral-Bright-Release.jpg 3. http://www.nasa.gov/ 4. http://www.jhuapl.edu/ 5. http://www.swri.edu/ 6. https://en.wikipedia.org/wiki/United_States_Naval_Observatory_Flagstaff_Station#/media/File:NOFS-pan2.jpg 7. https://en.wikipedia.org/wiki/Neverland_Regio 8. https://science.nasa.gov/dwarf-planets/pluto/moons/charon/ 9. https://pluto.jhuapl.edu/ 10. https://science.nasa.gov/mission/new-horizons/ 11. http://pluto.jhuapl.edu/Galleries/Featured-Images/image.php?page=1&gallery_id=2ℑ_id=323 12. https://www.nasa.gov/directorates/how-big-is-pluto-new-horizons-settles-decades-long-debate/ 13. https://www.nasa.gov/missions/charon-at-40-four-decades-of-discovery-on-plutos-largest-moon/ 14. https://apod.nasa.gov/apod/ap260605.html 15. https://apod.nasa.gov/apod/archivepix.html 16. https://apod.nasa.gov/apod/lib/apsubmit2015.html 17. https://apod.nasa.gov/apod/lib/aptree.html 18. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 19. https://apod.nasa.gov/apod/calendar/allyears.html 20. https://apod.com/feed.rss 21. https://apod.nasa.gov/apod/lib/edlinks.html 22. https://apod.nasa.gov/apod/lib/about_apod.html 23. https://asterisk.apod.com/discuss_apod.php?date=260606 24. https://apod.nasa.gov/apod/ap260607.html 25. http://www.phy.mtu.edu/faculty/Nemiroff.html 26. http://www.phy.mtu.edu/ 27. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 28. http://www.astro.umd.edu/ 29. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 30. https://www.nasa.gov/about/highlights/HP_Privacy.html 31. https://www.nasa.gov/general/accessibility/ 32. https://www.nasa.gov/privacy/ 33. https://astrophysics.gsfc.nasa.gov/ 34. https://www.nasa.gov/ 35. https://www.nasa.gov/centers/goddard/ 36. https://science.nasa.gov/learners 37. http://www.mtu.edu/