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.

                               2024 October 5
    [2]See Explanation. Clicking on the picture will download the highest
                        resolution version available.

                              M27: Not a Comet
    Image Credit & [3]Copyright: [4]Francesco Sferlazza, Franco Sgueglia

   Explanation: While hunting for comets in the skies above 18th century
   France, [5]astronomer Charles Messier diligently kept a list of the
   things encountered during his telescopic expeditions that were
   definitely not comets. This is number 27 on his [6]now famous
   not-a-comet list. In fact, 21st century astronomers would identify it
   as a [7]planetary nebula, but it's not a planet either, even though it
   may [8]appear round and planet-like in a small telescope. Messier 27
   (M27) is an excellent example of a gaseous emission nebula created as a
   [9]sun-like star runs out of nuclear fuel in its core. The nebula forms
   as the star's outer layers are expelled into space, with a visible glow
   generated by atoms excited by the dying star's intense but invisible
   [10]ultraviolet light. Known by the popular name of the [11]Dumbbell
   Nebula, the beautifully symmetric interstellar gas cloud is over 2.5
   light-years across and about 1,200 light-years away in the
   [12]constellation Vulpecula. This impressive color image highlights
   details within the well-studied central region and fainter, seldom
   imaged features in the nebula's [13]outer halo.

                     Tomorrow's picture: a comet's tale
     __________________________________________________________________

      [14]< | [15]Archive | [16]Submissions | [17]Index | [18]Search |
   [19]Calendar | [20]RSS | [21]Education | [22]About APOD | [23]Discuss |
                                    [24]>
     __________________________________________________________________

    Authors & editors: [25]Robert Nemiroff ([26]MTU) & [27]Jerry Bonnell
                                 ([28]UMCP)
          NASA Official: Phillip Newman [29]Specific rights apply.
              [30]NASA Web Privacy Policy and Important Notices
                A service of: [31]ASD at [32]NASA / [33]GSFC,
                         [34]NASA Science Activation
                           & [35]Michigan Tech. U.

References

   1. https://apod.nasa.gov/apod/archivepix.html
   2. https://apod.nasa.gov/apod/image/2410/m27_RGB_CC_FLAT_MEW.jpg
   3. https://apod.nasa.gov/apod/lib/about_apod.html#srapply
   4. http://www.astrobrallo.com/
   5. https://science.nasa.gov/people/explore-the-night-sky-hubbleatms-messier-catalog-bio/
   6. http://messier.seds.org/xtra/history/m-cat.html
   7. http://messier.seds.org/planetar.html
   8. https://apod.nasa.gov/apod/ap030614.html
   9. https://apod.nasa.gov/apod/ap100221.html
  10. http://imagine.gsfc.nasa.gov/science/toolbox/emspectrum1.html
  11. https://science.nasa.gov/mission/hubble/science/explore-the-night-sky/hubble-messier-catalog/messier-27/
  12. http://hawastsoc.org/deepsky/vul/index.html
  13. https://apod.nasa.gov/apod/ap100509.html
  14. https://apod.nasa.gov/apod/ap241004.html
  15. https://apod.nasa.gov/apod/archivepix.html
  16. https://apod.nasa.gov/apod/lib/apsubmit2015.html
  17. https://apod.nasa.gov/apod/lib/aptree.html
  18. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search
  19. https://apod.nasa.gov/apod/calendar/allyears.html
  20. https://apod.nasa.gov/apod.rss
  21. https://apod.nasa.gov/apod/lib/edlinks.html
  22. https://apod.nasa.gov/apod/lib/about_apod.html
  23. http://asterisk.apod.com/discuss_apod.php?date=241005
  24. https://apod.nasa.gov/apod/ap241006.html
  25. http://www.phy.mtu.edu/faculty/Nemiroff.html
  26. http://www.phy.mtu.edu/
  27. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html
  28. http://www.astro.umd.edu/
  29. https://apod.nasa.gov/apod/lib/about_apod.html#srapply
  30. https://www.nasa.gov/about/highlights/HP_Privacy.html
  31. https://astrophysics.gsfc.nasa.gov/
  32. https://www.nasa.gov/
  33. https://www.nasa.gov/centers/goddard/
  34. https://science.nasa.gov/learners
  35. http://www.mtu.edu/