¿ 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. 2021 January 13 [2]See Explanation. Moving the cursor over the image will bring up an annotated version. Clicking on the image will bring up the highest resolution version available. Arches Across an Arctic Sky Image Credit & Copyright: [3]Giulio Cobianchi Explanation: What are these two giant arches across the sky? Perhaps the more familiar one, on the left, is the central band of our [4]Milky Way Galaxy. This grand disk of stars and nebulas here appears to encircle much of the southern sky. Visible below the stellar arch is the [5]rusty-orange planet [6]Mars and the extended [7]Andromeda galaxy. For a few minutes during this [8]cold artic night, a second [9]giant arch appeared to the right, encircling part of the northern sky: an [10]aurora. Auroras are much closer than stars as they are composed of glowing air high in [11]Earth's atmosphere. Visible outside the [12]green auroral arch is the group of stars popularly [13]known as the [14]Big Dipper. The [15]featured digital composite of 18 images was captured in mid-December over the [16]in [17]Norway. APOD Year in Review (2020): [18]RJN's Night Sky Network Lecture Tomorrow's picture: open space __________________________________________________________________ [19]< | [20]Archive | [21]Submissions | [22]Index | [23]Search | [24]Calendar | [25]RSS | [26]Education | [27]About APOD | [28]Discuss | [29]> __________________________________________________________________ Authors & editors: [30]Robert Nemiroff ([31]MTU) & [32]Jerry Bonnell ([33]UMCP) NASA Official: Phillip Newman [34]Specific rights apply. [35]NASA Web Privacy Policy and Important Notices A service of: [36]ASD at [37]NASA / [38]GSFC & [39]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2101/ArcticSky_Cobianchi_2048.jpg 3. https://giuliocobianchi.com/about/ 4. https://solarsystem.nasa.gov/resources/285/the-milky-way-galaxy/ 5. https://apod.nasa.gov/apod/ap970804.html 6. https://solarsystem.nasa.gov/planets/mars/overview/ 7. https://apod.nasa.gov/apod/ap150830.html 8. https://pbs.twimg.com/media/DKSyMr2UEAAUL70?format=jpg 9. https://apod.nasa.gov/apod/ap200531.html 10. https://spaceplace.nasa.gov/aurora/en/ 11. https://www.nasa.gov/mission_pages/sunearth/science/atmosphere-layers2.html 12. https://apod.nasa.gov/apod/ap190322.html 13. https://apod.nasa.gov/apod/ap210112.html 14. https://en.wikipedia.org/wiki/Big_Dipper 15. https://giuliocobianchi.com/gallery/capture-the-night/ 16. https://youtu.be/mg67iIFivDo 17. https://en.wikipedia.org/wiki/Norway 18. https://youtu.be/smDKWEE77Gs?t=383 19. https://apod.nasa.gov/apod/ap210112.html 20. https://apod.nasa.gov/apod/archivepix.html 21. https://apod.nasa.gov/apod/lib/apsubmit2015.html 22. https://apod.nasa.gov/apod/lib/aptree.html 23. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 24. https://apod.nasa.gov/apod/calendar/allyears.html 25. https://apod.nasa.gov/apod.rss 26. https://apod.nasa.gov/apod/lib/edlinks.html 27. https://apod.nasa.gov/apod/lib/about_apod.html 28. http://asterisk.apod.com/discuss_apod.php?date=210113 29. https://apod.nasa.gov/apod/ap210114.html 30. http://www.phy.mtu.edu/faculty/Nemiroff.html 31. http://www.phy.mtu.edu/ 32. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 33. http://www.astro.umd.edu/ 34. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 35. https://www.nasa.gov/about/highlights/HP_Privacy.html 36. https://astrophysics.gsfc.nasa.gov/ 37. https://www.nasa.gov/ 38. https://www.nasa.gov/centers/goddard/ 39. http://www.mtu.edu/