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. 2020 January 4 [2]See Explanation. Clicking on the picture will download the highest resolution version available. Aurora Slathers Up the Sky Image Credit: [3]Jack Fischer, [4]Expedition 52, [5]NASA Explanation: Like salsa verde on your favorite burrito, a green [6]aurora slathers up the sky in this 2017 June 25 snapshot from the International Space Station. About 400 kilometers (250 miles) above Earth, the orbiting station is itself [7]within the upper realm of the auroral displays. Aurorae have the [8]signature colors of excited molecules and atoms at the low densities found at extreme altitudes. Emission from atomic oxygen dominates this view. [9]The tantalizing glow is green at lower altitudes, but rarer reddish bands extend above the space station's horizon. [10]The orbital scene was captured while passing over a point south and east of Australia, with stars above the horizon at the right belonging to the constellation [11]Canis Major, Orion's big dog. [12]Sirius, alpha star of Canis Major, is the brightest star near the Earth's limb. Tomorrow's picture: sauce serene __________________________________________________________________ [13]< | [14]Archive | [15]Submissions | [16]Index | [17]Search | [18]Calendar | [19]RSS | [20]Education | [21]About APOD | [22]Discuss | [23]> __________________________________________________________________ Authors & editors: [24]Robert Nemiroff ([25]MTU) & [26]Jerry Bonnell ([27]UMCP) NASA Official: Phillip Newman [28]Specific rights apply. [29]NASA Web Privacy Policy and Important Notices A service of: [30]ASD at [31]NASA / [32]GSFC & [33]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2001/aurora_iss052e007857.jpg 3. https://twitter.com/Astro2fish/ 4. https://www.nasa.gov/mission_pages/station/expeditions/expedition52/index.html 5. http://www.nasa.gov/ 6. https://twitter.com/Astro2fish/status/884886605407727616 7. http://ffden-2.phys.uaf.edu/211.fall2000.web.projects/Christina Shaw/AuroraColors.html 8. http://www.webexhibits.org/causesofcolor/4D.html 9. https://twitter.com/Astro2fish/status/889198201236008960 10. https://eol.jsc.nasa.gov/SearchPhotos/photo.pl?mission=ISS052&roll=E&frame=7857 11. http://www.hawastsoc.org/deepsky/cma/index.html 12. http://stars.astro.illinois.edu/sow/sirius.html 13. https://apod.nasa.gov/apod/ap200103.html 14. https://apod.nasa.gov/apod/archivepix.html 15. https://apod.nasa.gov/apod/lib/apsubmit2015.html 16. https://apod.nasa.gov/apod/lib/aptree.html 17. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 18. https://apod.nasa.gov/apod/calendar/allyears.html 19. https://apod.nasa.gov/apod.rss 20. https://apod.nasa.gov/apod/lib/edlinks.html 21. https://apod.nasa.gov/apod/lib/about_apod.html 22. http://asterisk.apod.com/discuss_apod.php?date=200104 23. https://apod.nasa.gov/apod/ap200105.html 24. http://www.phy.mtu.edu/faculty/Nemiroff.html 25. http://www.phy.mtu.edu/ 26. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 27. http://www.astro.umd.edu/ 28. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 29. https://www.nasa.gov/about/highlights/HP_Privacy.html 30. https://astrophysics.gsfc.nasa.gov/ 31. https://www.nasa.gov/ 32. https://www.nasa.gov/centers/goddard/ 33. http://www.mtu.edu/