¿

                        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 March 8
    [2]See Explanation. Moving the cursor over the image will bring up an
    annotated version. Clicking on the picture will download the highest
                        resolution version available.

                        Three Tails of Comet NEOWISE
               Image Credit & Copyright: [3]Nicolas Lefaudeux

   Explanation: What created the unusual red tail in Comet NEOWISE?
   [4]Sodium. A spectacular sight back in the summer of 2020, Comet
   NEOWISE, at times, displayed something more than just a [5]surprisingly
   [6]striated [7]white dust tail and a [8]pleasingly patchy blue [9]ion
   tail. Some color sensitive images showed an unusual red tail, and
   [10]analysis showed much of this third tail's color was emitted by
   sodium. Gas rich in sodium atoms might have been liberated from
   [11]Comet NEOWISE's warming nucleus in early July by bright sunlight,
   electrically charged by [12]ultraviolet sunlight, and then pushed out
   by the [13]solar wind. The [14]featured image was captured in mid-July
   from [15]Brittany, [16]France and shows the real colors. [17]Sodium
   comet tails have been seen before but are [18]rare -- this one
   disappeared by late July. [19]Comet C/2020 F3 (NEOWISE) has [20]since
   faded, lost all of its bright tails, and now approaches the orbit of
   [21]Jupiter as it heads back to the outer [22]Solar System, to return
   only in about 7,000 years.

     Astrophysicists: [23]Browse 2,400+ codes in the Astrophysics Source
                                Code Library
                        Tomorrow's picture: mars 360
     __________________________________________________________________

      [24]< | [25]Archive | [26]Submissions | [27]Index | [28]Search |
   [29]Calendar | [30]RSS | [31]Education | [32]About APOD | [33]Discuss |
                                    [34]>
     __________________________________________________________________

    Authors & editors: [35]Robert Nemiroff ([36]MTU) & [37]Jerry Bonnell
                                 ([38]UMCP)
          NASA Official: Phillip Newman [39]Specific rights apply.
              [40]NASA Web Privacy Policy and Important Notices
                A service of: [41]ASD at [42]NASA / [43]GSFC
                           & [44]Michigan Tech. U.

References

   1. https://apod.nasa.gov/apod/archivepix.html
   2. https://apod.nasa.gov/apod/image/2103/Neowise3Tails_Lefaudeux_1088.jpg
   3. https://hdr-astrophotography.com/a-propos/
   4. https://youtu.be/dmcfsEEogxs?t=49
   5. https://apod.nasa.gov/apod/ap200722.html
   6. https://link.springer.com/article/10.1007/BF00644193
   7. https://apod.nasa.gov/apod/ap200722.html
   8. https://i.redd.it/58if334dkzm31.jpg
   9. https://en.wikipedia.org/wiki/Comet_tail
  10. https://ui.adsabs.harvard.edu/abs/2020DPS....5211102Y/abstract
  11. https://apod.nasa.gov/apod/ap200812.html
  12. https://science.nasa.gov/ems/10_ultravioletwaves
  13. https://solarsystem.nasa.gov/resources/2288/the-solar-wind-across-our-solar-system/
  14. https://hdr-astrophotography.com/
  15. https://youtu.be/IG4H6gS3SNk
  16. https://en.wikipedia.org/wiki/France
  17. https://astronomy.swin.edu.au/cosmos/c/Cometary+Neutral+Tail
  18. https://www.nsf.gov/discoveries/disc_summ.jsp?cntn_id=300913
  19. https://en.wikipedia.org/wiki/Comet_NEOWISE
  20. https://theskylive.com/c2020f3-info
  21. https://solarsystem.nasa.gov/planets/jupiter/overview/
  22. https://solarsystem.nasa.gov/solar-system/our-solar-system/in-depth/
  23. http://ascl.net/
  24. https://apod.nasa.gov/apod/ap210307.html
  25. https://apod.nasa.gov/apod/archivepix.html
  26. https://apod.nasa.gov/apod/lib/apsubmit2015.html
  27. https://apod.nasa.gov/apod/lib/aptree.html
  28. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search
  29. https://apod.nasa.gov/apod/calendar/allyears.html
  30. https://apod.nasa.gov/apod.rss
  31. https://apod.nasa.gov/apod/lib/edlinks.html
  32. https://apod.nasa.gov/apod/lib/about_apod.html
  33. http://asterisk.apod.com/discuss_apod.php?date=210308
  34. https://apod.nasa.gov/apod/ap210309.html
  35. http://www.phy.mtu.edu/faculty/Nemiroff.html
  36. http://www.phy.mtu.edu/
  37. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html
  38. http://www.astro.umd.edu/
  39. https://apod.nasa.gov/apod/lib/about_apod.html#srapply
  40. https://www.nasa.gov/about/highlights/HP_Privacy.html
  41. https://astrophysics.gsfc.nasa.gov/
  42. https://www.nasa.gov/
  43. https://www.nasa.gov/centers/goddard/
  44. http://www.mtu.edu/