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 February 12 [2]See Explanation. Clicking on the picture will download the highest resolution version available. Star Trails of the North and South Image Credit & Copyright: [3]Saeid Parchini Explanation: What divides the north from the south? It all has to do with the spin of [4]the Earth. On Earth's surface, [5]the equator is the dividing line, but on Earth's sky, the dividing line is the [6]Celestial Equator -- the equator's projection onto the sky. You likely can't see the Earth's equator around you, but anyone with a [7]clear night sky can find the [8]Celestial Equator by watching stars move. Just [9]locate the dividing line between [10]stars that arc north and stars that arc south. Were you on Earth's equator, the Celestial Equator would go straight up and down. [11]In general, the angle between the Celestial Equator and the vertical is your [12]latitude. The featured image combines 325 photos taken every 30 seconds over 162 minutes. Taken soon after sunset earlier this month, [13]moonlight illuminates a snowy and desolate scene in northwest [14]Iran. The bright streak behind the [15]lone tree is the planet [16]Venus setting[17]. Almost Hyperspace: [18]Random APOD Generator 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/2002/StarTrailsTree_Parchini_4000.jpg 3. mailto: saeid.parchini @at@ yahoo .dot. com 4. https://solarsystem.nasa.gov/planets/earth/overview/ 5. https://www.nasa.gov/audience/forstudents/k-4/dictionary/Equator.html 6. https://en.wikipedia.org/wiki/Celestial_equator 7. https://apod.nasa.gov/apod/ap180208.html 8. https://www-istp.gsfc.nasa.gov/stargaze/Scelsph.htm 9. https://en.wikipedia.org/wiki/Tracking_(dog)#/media/File:Male_Weimeraner_Following_a_Scent_Trail_in_the_Snow.jpg 10. https://apod.nasa.gov/apod/ap190321.html 11. https://www.aa.quae.nl/en/antwoorden/hemel.html 12. https://c.tadst.com/gfx/750x500/longitude-and-latitude-simple.png 13. https://apod.nasa.gov/apod/ap170608.html 14. https://en.wikipedia.org/wiki/Iran 15. https://apod.nasa.gov/apod/ap200113.html 16. https://apod.nasa.gov/apod/ap120508.html 17. https://vimeo.com/37752523?autoplay-1#t=1m52s 18. https://apod.nasa.gov/apod/random_apod.html 19. https://apod.nasa.gov/apod/ap200211.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=200212 29. https://apod.nasa.gov/apod/ap200213.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/