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 April 25 [2]See Explanation. Clicking on the picture will download the highest resolution version available. The Persistence of Sunlight Image Credit & [3]Copyright: [4]Lorenzo Busilacchi Explanation: This seaside [5]sunset offered a surreal experience, captured in a sea and skyscape from the west coast of Sardinia, Italy, planet Earth. The Daliesque scene [6]is a composition of sequential exposures made with a camera and long telephoto lens. The Sun is [7]not melting, though. Its shifting and fluid appearance as it nears the horizon is caused as refraction along the line of sight changes and creates distorted images or [8]mirages of the reddened solar disk. The changes in atmospheric refraction correspond to [9]atmospheric layers with sharply different temperatures and densities. Another famous but fleeting effect of atmospheric refraction produced by a long sight-line to the setting (or rising) Sun is often called [10]the green flash. Tomorrow's picture: mystic mountain monster __________________________________________________________________ [11]< | [12]Archive | [13]Submissions | [14]Index | [15]Search | [16]Calendar | [17]RSS | [18]Education | [19]About APOD | [20]Discuss | [21]> __________________________________________________________________ Authors & editors: [22]Robert Nemiroff ([23]MTU) & [24]Jerry Bonnell ([25]UMCP) NASA Official: Amber Straughn [26]Specific rights apply. [27]NASA Web Privacy, [28]Accessibility, [29]Notices; A service of: [30]ASD at [31]NASA / [32]GSFC, [33]NASA Science Activation & [34]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2604/sequenzasunsetnebida.jpg 3. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 4. https://www.instagram.com/lorenzo.busilacchi/ 5. https://www.nasa.gov/solar-system/nasa-scientist-simulates-sunsets-on-other-worlds/ 6. https://www.instagram.com/lorenzo.busilacchi/p/DXcZVbLjZvR/ 7. https://en.wikipedia.org/wiki/The_Persistence_of_Memory 8. https://www.atoptics.org.uk/atoptics/mmirsun.htm 9. https://apod.nasa.gov/apod/ap170120.html 10. https://apod.nasa.gov/apod/ap231025.html 11. https://apod.nasa.gov/apod/ap260424.html 12. https://apod.nasa.gov/apod/archivepix.html 13. https://apod.nasa.gov/apod/lib/apsubmit2015.html 14. https://apod.nasa.gov/apod/lib/aptree.html 15. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 16. https://apod.nasa.gov/apod/calendar/allyears.html 17. https://apod.com/feed.rss 18. https://apod.nasa.gov/apod/lib/edlinks.html 19. https://apod.nasa.gov/apod/lib/about_apod.html 20. https://asterisk.apod.com/discuss_apod.php?date=260425 21. https://apod.nasa.gov/apod/ap260426.html 22. http://www.phy.mtu.edu/faculty/Nemiroff.html 23. http://www.phy.mtu.edu/ 24. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 25. http://www.astro.umd.edu/ 26. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 27. https://www.nasa.gov/about/highlights/HP_Privacy.html 28. https://www.nasa.gov/general/accessibility/ 29. https://www.nasa.gov/privacy/ 30. https://astrophysics.gsfc.nasa.gov/ 31. https://www.nasa.gov/ 32. https://www.nasa.gov/centers/goddard/ 33. https://science.nasa.gov/learners 34. http://www.mtu.edu/