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. 2024 May 13 [2]A distant Sun is seen over water and between foreground trees. On the lower part of the Sun is the gigantic active region AR 3664 visible by its dark sunspots. Please see the explanation for more detailed information. AR 3664 on a Setting Sun Image Credit & Copyright: [3]Marco Meniero Explanation: It was larger than the Earth. It was so big you could actually see it on the Sun's surface without magnification. It contained powerful and [4]tangled magnetic fields as well as numerous [5]dark sunspots. Labelled [6]AR 3664, it developed into one of the most energetic areas seen on the [7]Sun in recent years, unleashing a series of explosions that led to a surge of energetic particles striking the Earth, which created [8]beautiful auroras. [9]And might continue. Although [10]active regions on the Sun like AR 3664 can be quite dangerous, this region's [11]Coronal Mass Ejections have not done, as yet, much [12]damage to Earth-orbiting satellites or [13]Earth-surface electrical grids. [14]Pictured, the enormous active region was captured on the setting Sun a few days ago from [15]Civitavecchia, [16]Rome, [17]Italy. The [18]composite image includes a very short exposure taken of just the [19]Sun's surface, but mimics what was actually visible. Finally, [20]AR 3664 is [21]now rotating away from the Earth, although the region may survive long enough to [22]come around again. Gallery: [23]Earth Aurora from Solar Active Region 6443 Tomorrow's picture: What is 42 - 5? __________________________________________________________________ [24]< | [25]Archive | [26]Submissions | [27]Index | [28]Search | [29]Calendar | [30]RSS | [31]Education | [32]About APOD | [33]Discuss | [34]> __________________________________________________________________ Authors & editors: [35]Robert Nemiroff ([36]MTU) & [37]Jerry Bonnell ([38]UMCP) NASA Official: Amber Straughn [39]Specific rights apply. [40]NASA Web Privacy, [41]Accessibility, [42]Notices; A service of: [43]ASD at [44]NASA / [45]GSFC, [46]NASA Science Activation & [47]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2405/SunAr3664_Menario_1508.jpg 3. https://www.facebook.com/marco.meniero 4. https://www.spaceweatherlive.com/en/help/the-magnetic-classification-of-sunspots.html 5. https://en.wikipedia.org/wiki/Sunspot 6. https://apod.nasa.gov/apod/ap240511.html 7. https://science.nasa.gov/sun/ 8. https://apod.nasa.gov/apod/ap240512.html 9. https://www.swpc.noaa.gov/products/aurora-viewline-tonight-and-tomorrow-night-experimental 10. https://science.nasa.gov/get-involved/citizen-science/be-a-solar-active-region-spotter/ 11. https://apod.nasa.gov/apod/ap180902.html 12. https://svs.gsfc.nasa.gov/5214/ 13. https://www.swpc.noaa.gov/sites/default/files/images/u33/finalBoulderPresentation042611 (1).pdf 14. https://www.facebook.com/photo/?fbid=431389876256262&set=a.431368006258449 15. https://youtu.be/mL__aBb8Hlg 16. https://youtu.be/oSexfR0Ubzw 17. https://en.wikipedia.org/wiki/Italy 18. https://www.facebook.com/photo/?fbid=431389876256262&set=a.431368006258449 19. https://apod.nasa.gov/apod/ap111106.html 20. https://spaceweather.com/images2024/12may24/hmi1898.gif 21. https://m.media-amazon.com/images/I/51ZjBEW+qNL._AC_UF894,1000_QL80_.jpg 22. https://t4.ftcdn.net/jpg/01/90/92/89/360_F_190928973_1rQ1nipXxnL6Y28MIL5OlY69MNFTsM9k.jpg 23. https://www.facebook.com/media/set?set=a.431368006258449&type=3 24. https://apod.nasa.gov/apod/ap240512.html 25. https://apod.nasa.gov/apod/archivepix.html 26. https://apod.nasa.gov/apod/lib/apsubmit2015.html 27. https://apod.nasa.gov/apod/lib/aptree.html 28. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 29. https://apod.nasa.gov/apod/calendar/allyears.html 30. https://apod.com/feed.rss 31. https://apod.nasa.gov/apod/lib/edlinks.html 32. https://apod.nasa.gov/apod/lib/about_apod.html 33. https://asterisk.apod.com/discuss_apod.php?date=240513 34. https://apod.nasa.gov/apod/ap240514.html 35. http://www.phy.mtu.edu/faculty/Nemiroff.html 36. http://www.phy.mtu.edu/ 37. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 38. http://www.astro.umd.edu/ 39. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 40. https://www.nasa.gov/about/highlights/HP_Privacy.html 41. https://www.nasa.gov/general/accessibility/ 42. https://www.nasa.gov/privacy/ 43. https://astrophysics.gsfc.nasa.gov/ 44. https://www.nasa.gov/ 45. https://www.nasa.gov/centers/goddard/ 46. https://science.nasa.gov/learners 47. http://www.mtu.edu/