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.

                                2022 July 31
     [2]The featured image shows a bright center surrounded by dark dust
    lanes and wide ring of bright blue stars. Please see the explanation
                       for more detailed information.

                      Starburst Galaxy M94 from Hubble
                    Image Credit: [3]ESA/Hubble & [4]NASA

   Explanation: Why does this galaxy have a ring of bright blue stars?
   Beautiful island universe [5]Messier 94 lies a mere 15 million
   light-years distant in the northern constellation of the Hunting Dogs
   ([6]Canes Venatici). A popular target for [7]Earth-based astronomers,
   the face-on spiral galaxy is about 30,000 [8]light-years across, with
   spiral arms sweeping through the [9]outskirts of its broad disk. But
   this [10]Hubble Space Telescope field of view spans about 7,000
   light-years across [11]M94's central region. The [12]featured close-up
   highlights the galaxy's compact, bright nucleus, prominent inner
   [13]dust lanes, and the [14]remarkable bluish ring of young massive
   stars. The ring stars are all likely less than 10 million years old,
   indicating that M94 is a [15]starburst galaxy that is experiencing an
   epoch of rapid star formation from inspiraling gas. The circular ripple
   of blue stars is likely a [16]wave propagating outward, having been
   [17]triggered by the gravity and rotation of a [18]oval matter
   distributions. Because M94 is relatively nearby, [19]astronomers can
   better explore [20]details of its starburst ring.

                     Tomorrow's picture: space mountain
     __________________________________________________________________

      [21]< | [22]Archive | [23]Submissions | [24]Index | [25]Search |
   [26]Calendar | [27]RSS | [28]Education | [29]About APOD | [30]Discuss |
                                    [31]>
     __________________________________________________________________

    Authors & editors: [32]Robert Nemiroff ([33]MTU) & [34]Jerry Bonnell
                                 ([35]UMCP)
          NASA Official: Phillip Newman [36]Specific rights apply.
              [37]NASA Web Privacy Policy and Important Notices
                A service of: [38]ASD at [39]NASA / [40]GSFC,
                         [41]NASA Science Activation
                           & [42]Michigan Tech. U.

References

   1. https://apod.nasa.gov/apod/archivepix.html
   2. https://apod.nasa.gov/apod/image/2207/M94_Hubble_960.jpg
   3. https://esahubble.org/
   4. https://www.nasa.gov/
   5. https://en.wikipedia.org/wiki/Messier_94
   6. https://en.wikipedia.org/wiki/Canes_Venatici
   7. https://solarsystem.nasa.gov/planets/earth/overview/
   8. https://spaceplace.nasa.gov/light-year/en/
   9. https://apod.nasa.gov/apod/ap100114.html
  10. https://esahubble.org/images/potw1542a/
  11. https://apod.nasa.gov/apod/ap150526.html
  12. https://esahubble.org/images/potw1542a/zoomable/
  13. https://apod.nasa.gov/apod/ap180322.html
  14. https://i.redd.it/kn7wz036va161.jpg
  15. https://apod.nasa.gov/apod/ap191009.html
  16. https://ui.adsabs.harvard.edu/abs/2004ARA&A..42..603K/abstract
  17. https://ui.adsabs.harvard.edu/abs/2004ASSL..319..261K/abstract
  18. https://apod.nasa.gov/apod/ap181009.html
  19. https://www.iau.org/public/themes/careers/
  20. https://ui.adsabs.harvard.edu/abs/2001AJ....121.1395W/abstract
  21. https://apod.nasa.gov/apod/ap220730.html
  22. https://apod.nasa.gov/apod/archivepix.html
  23. https://apod.nasa.gov/apod/lib/apsubmit2015.html
  24. https://apod.nasa.gov/apod/lib/aptree.html
  25. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search
  26. https://apod.nasa.gov/apod/calendar/allyears.html
  27. https://apod.nasa.gov/apod.rss
  28. https://apod.nasa.gov/apod/lib/edlinks.html
  29. https://apod.nasa.gov/apod/lib/about_apod.html
  30. http://asterisk.apod.com/discuss_apod.php?date=220731
  31. https://apod.nasa.gov/apod/ap220801.html
  32. http://www.phy.mtu.edu/faculty/Nemiroff.html
  33. http://www.phy.mtu.edu/
  34. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html
  35. http://www.astro.umd.edu/
  36. https://apod.nasa.gov/apod/lib/about_apod.html#srapply
  37. https://www.nasa.gov/about/highlights/HP_Privacy.html
  38. https://astrophysics.gsfc.nasa.gov/
  39. https://www.nasa.gov/
  40. https://www.nasa.gov/centers/goddard/
  41. https://science.nasa.gov/learners
  42. http://www.mtu.edu/