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 December 3 [2]See Explanation. Clicking on the picture will download the highest resolution version available. Comet Leonard and the Whale Galaxy Image Credit & [3]Copyright: [4]Gregg Ruppel Explanation: [5]Sweeping through northern predawn skies, on November 24 [6]Comet Leonard (C/2021 A1) was caught between two galaxies in this [7]composite telescopic image. Sporting a greenish coma the comet's dusty tail seems to harpoon the [8]heart of NGC 4631 (top) also known as the Whale Galaxy. Of course [9]NGC 4631 and NGC 4656 (bottom, aka the Hockey Stick) are background galaxies some 25 million light-years away. On that date the comet was about 6 light-minutes from our fair planet. Its closest approach to Earth (and even closer approach [10]to Venus) still to come, [11]Comet Leonard will grow brighter in December. [12]Already a good object for binoculars and small telescopes, this comet will likely not return to the inner Solar System. Its perihelion, or closest approach to the Sun, will be on January 3, 2022. Tomorrow's picture: light-weekend __________________________________________________________________ [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/2112/ngc4656_4631_A1-LRGB_112421.jpg 3. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 4. http://www.greggsastronomy.com/ 5. https://apod.nasa.gov/apod/ap211121.html 6. https://theskylive.com/cometleonard-info 7. http://www.greggsastronomy.com/c2021%20A1%20Leonard.html 8. https://apod.nasa.gov/apod/ap100517.html 9. https://apod.nasa.gov/apod/ap090821.html 10. https://arxiv.org/abs/2107.12370 11. https://earthsky.org/astronomy-essentials/comet-leonard-might-become-2021s-brightest-2022/ 12. https://solarsystem.nasa.gov/resources/2671/whats-up-december-2021/ 13. https://apod.nasa.gov/apod/ap211202.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=211203 23. https://apod.nasa.gov/apod/ap211204.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/