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 August 22
   [2]The picture shows an illustration of binary star system RS Ophiuchus
    during a nova-causing explosion. Please see the explanation for more
                            detailed information.

                   Explosions from White Dwarf Star RS Oph
        Illustration Credit & Copyright: [3]David A. Hardy & [4]PPARC

   Explanation: Spectacular explosions keep occurring in the binary star
   system named [5]RS Ophiuchi. Every 20 years or so, the [6]red giant
   star dumps enough [7]hydrogen gas onto its companion white dwarf star
   to set off a brilliant [8]thermonuclear explosion on the [9]white
   dwarf's surface. At about 5,000 [10]light years distant, the resulting
   [11]nova explosions cause the [12]RS Oph system to brighten up by a
   huge factor and become visible to the unaided eye. The red giant star
   is depicted on the right of the [13]above drawing, while the white
   dwarf is at the center of the bright [14]accretion disk on the left. As
   the [15]stars orbit each other, a stream of [16]gas moves from the
   giant star to the white dwarf. [17]Astronomers [18]speculate that at
   some time in the next 100,000 years, enough matter will have
   accumulated on the [19]white dwarf to push it over the
   [20]Chandrasekhar Limit, causing a much more powerful and final
   explosion known as a [21]supernova. Starting early this month, [22]RS
   Oph was again [23]seen exploding in a [24]bright nova.

                   Tomorrow's picture: one galaxy tripled
     __________________________________________________________________

      [25]< | [26]Archive | [27]Submissions | [28]Index | [29]Search |
   [30]Calendar | [31]RSS | [32]Education | [33]About APOD | [34]Discuss |
                                    [35]>
     __________________________________________________________________

    Authors & editors: [36]Robert Nemiroff ([37]MTU) & [38]Jerry Bonnell
                                 ([39]UMCP)
          NASA Official: Phillip Newman [40]Specific rights apply.
              [41]NASA Web Privacy Policy and Important Notices
                A service of: [42]ASD at [43]NASA / [44]GSFC
                           & [45]Michigan Tech. U.

References

   1. https://apod.nasa.gov/apod/archivepix.html
   2. https://apod.nasa.gov/apod/image/2108/rsoph_pparc_2953.jpg
   3. https://www.astroart.org/hardy-profile
   4. https://en.wikipedia.org/wiki/Particle_Physics_and_Astronomy_Research_Council
   5. https://en.wikipedia.org/wiki/RS_Oph
   6. https://en.wikipedia.org/wiki/Red_giant
   7. https://periodic.lanl.gov/1.shtml
   8. https://youtu.be/c6W2suGacjQ
   9. https://apod.nasa.gov/apod/ap100221.html
  10. https://chandra.harvard.edu/photo/cosmic_distance.html
  11. https://en.wikipedia.org/wiki/Nova
  12. https://ui.adsabs.harvard.edu/abs/2001ApJ...558..323H/abstract
  13. http://www.jb.man.ac.uk/news/rsoph-radio/
  14. https://apod.nasa.gov/apod/ap200831.html
  15. https://science.nasa.gov/astrophysics/focus-areas/how-do-stars-form-and-evolve
  16. http://news.bbc.co.uk/2/hi/science/nature/5204676.stm
  17. https://aas.org/careers/career-profiles
  18. https://render.fineartamerica.com/images/rendered/default/greeting-card/images/artworkimages/medium/1/auburn-handsome-cat-thinking-about-life-natalia-o.jpg
  19. https://apod.nasa.gov/apod/ap000910.html
  20. https://en.wikipedia.org/wiki/Chandrasekhar_limit
  21. https://en.wikipedia.org/wiki/Supernova#Type_Ia
  22. https://www.aavso.org/vsots_rsoph
  23. https://skyandtelescope.org/astronomy-news/recurrent-nova-rs-ophiuchi-just-blew-its-top/
  24. https://apod.nasa.gov/apod/ap210816.html
  25. https://apod.nasa.gov/apod/ap210821.html
  26. https://apod.nasa.gov/apod/archivepix.html
  27. https://apod.nasa.gov/apod/lib/apsubmit2015.html
  28. https://apod.nasa.gov/apod/lib/aptree.html
  29. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search
  30. https://apod.nasa.gov/apod/calendar/allyears.html
  31. https://apod.nasa.gov/apod.rss
  32. https://apod.nasa.gov/apod/lib/edlinks.html
  33. https://apod.nasa.gov/apod/lib/about_apod.html
  34. http://asterisk.apod.com/discuss_apod.php?date=210822
  35. https://apod.nasa.gov/apod/ap210823.html
  36. http://www.phy.mtu.edu/faculty/Nemiroff.html
  37. http://www.phy.mtu.edu/
  38. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html
  39. http://www.astro.umd.edu/
  40. https://apod.nasa.gov/apod/lib/about_apod.html#srapply
  41. https://www.nasa.gov/about/highlights/HP_Privacy.html
  42. https://astrophysics.gsfc.nasa.gov/
  43. https://www.nasa.gov/
  44. https://www.nasa.gov/centers/goddard/
  45. http://www.mtu.edu/