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 September 21 [2]See Explanation. Clicking on the picture will download the highest resolution version available. Sunrise Shadows in the Sky Image Credit & [3]Copyright: [4]Emili Vilamala Explanation: [5]The defining astronomical moment of this September's equinox is at 12:44 UTC on September 22, when the Sun crosses the celestial equator moving south in its [6]yearly journey through planet Earth's sky. That marks the beginning of [7]fall for our fair planet in the northern hemisphere and spring in the southern hemisphere, when day and night are nearly equal around the globe. Of course, if you celebrate the astronomical change of seasons by watching a sunrise you can also [8]look for crepuscular rays. Outlined by shadows cast by clouds, crepuscular rays can have a dramatic appearance in the twilight sky during any sunrise (or sunset). Due to perspective, the parallel cloud shadows will seem to point back to the rising Sun [9]and a place due east on your horizon on the equinox date. But in this spectacular sunrise skyscape captured in early June, the parallel shadows and crepuscular rays appear to converge toward an eastern horizon's more northerly sunrise. The well-composed photo places the rising Sun just behind the bell tower of a church in the town of Vic, province of Barcelona, Catalonia, Spain. Tomorrow's picture: Equinox in the City __________________________________________________________________ [10]< | [11]Archive | [12]Submissions | [13]Index | [14]Search | [15]Calendar | [16]RSS | [17]Education | [18]About APOD | [19]Discuss | [20]> __________________________________________________________________ Authors & editors: [21]Robert Nemiroff ([22]MTU) & [23]Jerry Bonnell ([24]UMCP) NASA Official: Phillip Newman [25]Specific rights apply. [26]NASA Web Privacy Policy and Important Notices A service of: [27]ASD at [28]NASA / [29]GSFC, [30]NASA Science Activation & [31]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2409/RayosCrepusculares.jpg 3. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 4. https://www.instagram.com/emili_vilamala/ 5. https://earthsky.org/astronomy-essentials/everything-you-need-to-know-september-equinox/ 6. https://apod.nasa.gov/apod/ap220918.html 7. https://www.timeanddate.com/calendar/autumnal-equinox.html 8. https://earthobservatory.nasa.gov/images/76261/crepuscular-rays-india 9. https://apod.nasa.gov/apod/ap160922.html 10. https://apod.nasa.gov/apod/ap240920.html 11. https://apod.nasa.gov/apod/archivepix.html 12. https://apod.nasa.gov/apod/lib/apsubmit2015.html 13. https://apod.nasa.gov/apod/lib/aptree.html 14. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 15. https://apod.nasa.gov/apod/calendar/allyears.html 16. https://apod.nasa.gov/apod.rss 17. https://apod.nasa.gov/apod/lib/edlinks.html 18. https://apod.nasa.gov/apod/lib/about_apod.html 19. http://asterisk.apod.com/discuss_apod.php?date=240921 20. https://apod.nasa.gov/apod/ap240922.html 21. http://www.phy.mtu.edu/faculty/Nemiroff.html 22. http://www.phy.mtu.edu/ 23. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 24. http://www.astro.umd.edu/ 25. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 26. https://www.nasa.gov/about/highlights/HP_Privacy.html 27. https://astrophysics.gsfc.nasa.gov/ 28. https://www.nasa.gov/ 29. https://www.nasa.gov/centers/goddard/ 30. https://science.nasa.gov/learners 31. http://www.mtu.edu/