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 October 12 [2]The picture shows a bright meteor fireball over Lake Louise in Alberta, Canada. Please see the explanation for more detailed information. Fireball over Lake Louise Image Credit & Copyright: [3]Hao Qin Explanation: What makes a meteor a fireball? First of all, everyone agrees that a [4]fireball is an exceptionally bright meteor. Past that, the [5]International Astronomical Union [6]defines a fireball as a meteor brighter than [7]apparent magnitude -4, which corresponds (roughly) to being brighter than any planet -- as well as bright enough to cast a human-noticeable shadow. Pictured, an astrophotographer taking a long-duration sky image captured by accident the brightest [8]meteor he had ever seen. Clearly a [9]fireball, the disintegrating space-rock created a trail so bright it [10]turned night into day for about two seconds earlier this month. The [11]fireball has been artificially dimmed in the featured image to bring up foreground [12]Lake Louise in [13]Alberta, [14]Canada. Although [15]fireballs are rare, many people have been lucky enough to see them. If [16]you see a fireball, you can [17]report it. If more than one person recorded an image, the [18]fireball might be [19]traceable back to the [20]Solar System body from which it was [21]ejected. Tomorrow's picture: big question __________________________________________________________________ [22]< | [23]Archive | [24]Submissions | [25]Index | [26]Search | [27]Calendar | [28]RSS | [29]Education | [30]About APOD | [31]Discuss | [32]> __________________________________________________________________ Authors & editors: [33]Robert Nemiroff ([34]MTU) & [35]Jerry Bonnell ([36]UMCP) NASA Official: Phillip Newman [37]Specific rights apply. [38]NASA Web Privacy Policy and Important Notices A service of: [39]ASD at [40]NASA / [41]GSFC & [42]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2110/FireballAlberta_Qin_5568.jpg 3. mailto:%20qinhao6999%20at%20gmail%20dot%20com 4. https://apod.nasa.gov/apod/ap171225.html 5. https://www.iau.org/administration/about/ 6. https://www.iau.org/public/themes/meteors_and_meteorites/ 7. https://en.wikipedia.org/wiki/Apparent_magnitude 8. https://solarsystem.nasa.gov/asteroids-comets-and-meteors/meteors-and-meteorites/overview/ 9. https://apod.nasa.gov/apod/ap210315.html 10. https://apod.nasa.gov/apod/ap130218.html 11. https://cneos.jpl.nasa.gov/fireballs/ 12. https://youtu.be/4K5sCmRV54Y 13. https://en.wikipedia.org/wiki/Alberta 14. https://en.wikipedia.org/wiki/Canada 15. https://apod.nasa.gov/apod/ap130209.html 16. https://i.pinimg.com/550x/81/21/c0/8121c0291fa14d1fe52b9eb007741cac.jpg 17. https://www.imo.net/fireball-over-adriatic-sea-on-august-18/ 18. https://fireballs.ndc.nasa.gov/ 19. https://apod.nasa.gov/apod/ap090511.html 20. https://solarsystem.nasa.gov/solar-system/our-solar-system/overview/ 21. https://apod.nasa.gov/apod/ap200916.html 22. https://apod.nasa.gov/apod/ap211011.html 23. https://apod.nasa.gov/apod/archivepix.html 24. https://apod.nasa.gov/apod/lib/apsubmit2015.html 25. https://apod.nasa.gov/apod/lib/aptree.html 26. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 27. https://apod.nasa.gov/apod/calendar/allyears.html 28. https://apod.nasa.gov/apod.rss 29. https://apod.nasa.gov/apod/lib/edlinks.html 30. https://apod.nasa.gov/apod/lib/about_apod.html 31. http://asterisk.apod.com/discuss_apod.php?date=211012 32. https://apod.nasa.gov/apod/ap211013.html 33. http://www.phy.mtu.edu/faculty/Nemiroff.html 34. http://www.phy.mtu.edu/ 35. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 36. http://www.astro.umd.edu/ 37. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 38. https://www.nasa.gov/about/highlights/HP_Privacy.html 39. https://astrophysics.gsfc.nasa.gov/ 40. https://www.nasa.gov/ 41. https://www.nasa.gov/centers/goddard/ 42. http://www.mtu.edu/