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 December 22
     [2]An artist's illustration shows where our Sun resides relative to
    local interstellar gas. The direction of motion of the Sun and local
   gas is shown with arrows. Please see the explanation for more detailed
                                information.

                               The Local Fluff
       Illustration Credit: [3]NASA, [4]SVS, [5]Adler, [6]U. Chicago,
                                 [7]Wesleyan

   Explanation: The stars are not alone. In the disk of our [8]Milky Way
   Galaxy, about 10 percent of visible matter is in the form of gas called
   the [9]interstellar medium (ISM). The ISM is [10]not uniform and shows
   [11]patchiness even near our [12]Sun. It can be quite difficult to
   detect the [13]local ISM because it is so tenuous and emits so little
   light. This mostly [14]hydrogen gas, however, absorbs some very
   specific colors that can be detected in the light of the [15]nearest
   stars. A working map of the local [16]ISM within 20 light-years, based
   on ongoing observations and particle detections from the Earth-orbiting
   Interstellar Boundary Exporer satellite ([17]IBEX), is [18]shown here.
   These observations indicate that our [19]Sun is moving through a
   [20]Local Interstellar Cloud as this cloud flows outwards from the
   [21]Scorpius-Centaurus Association star forming [22]region. Our Sun may
   exit the [23]Local Cloud, also called the Local Fluff, during the next
   10,000 years. Much remains unknown about the local [24]ISM, including
   details of its distribution, its origin, and how it affects the [25]Sun
   and the [26]Earth. [27]Unexpectedly, IBEX [28]spacecraft measurements
   indicate that the [29]direction from which neutral [30]interstellar
   particles flow through our Solar System [31]is changing.

      APOD Year in Review: [32]Night Sky Network Presentation for 2024
                        Tomorrow's picture: sky tree
     __________________________________________________________________

      [33]< | [34]Archive | [35]Submissions | [36]Index | [37]Search |
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     __________________________________________________________________

    Authors & editors: [44]Robert Nemiroff ([45]MTU) & [46]Jerry Bonnell
                                 ([47]UMCP)
          NASA Official: Amber Straughn [48]Specific rights apply.
            [49]NASA Web Privacy, [50]Accessibility, [51]Notices;
                A service of: [52]ASD at [53]NASA / [54]GSFC,
                         [55]NASA Science Activation
                           & [56]Michigan Tech. U.

References

   1. https://apod.nasa.gov/apod/archivepix.html
   2. https://apod.nasa.gov/apod/image/2412/LocalCloud_ibex_5580.jpg
   3. https://www.nasa.gov/
   4. https://svs.gsfc.nasa.gov/
   5. https://www.adlerplanetarium.org/
   6. https://astrophysics.uchicago.edu/
   7. https://www.wesleyan.edu/astro/
   8. https://science.nasa.gov/resource/the-milky-way-galaxy/
   9. http://www-ssg.sr.unh.edu/ism/what1.html
  10. https://en.wikipedia.org/wiki/Local_Bubble
  11. https://apod.nasa.gov/apod/ap990503.html
  12. https://spaceplace.nasa.gov/menu/sun/
  13. http://en.wikipedia.org/wiki/Local_Interstellar_Cloud
  14. http://periodic.lanl.gov/1.shtml
  15. http://www.atlasoftheuniverse.com/20lys.html
  16. https://apod.nasa.gov/apod/ap980225.html
  17. http://en.wikipedia.org/wiki/IBEX
  18. https://svs.gsfc.nasa.gov/10906/
  19. https://apod.nasa.gov/apod/ap020217.html
  20. https://en.wikipedia.org/wiki/Local_Interstellar_Cloud
  21. https://en.wikipedia.org/wiki/Scorpius–Centaurus_Association
  22. http://www.youtube.com/watch?v=DB2stJnmubc#t=28
  23. http://arxiv.org/abs/0804.3798
  24. https://en.wikipedia.org/wiki/Interstellar_medium
  25. https://science.nasa.gov/sun/
  26. https://apod.nasa.gov/apod/ap220206.html
  27. https://i.imgflip.com/eyvnj.jpg
  28. https://science.nasa.gov/mission/ibex/
  29. http://news.uchicago.edu/article/2013/09/06/spacecraft-measures-changes-direction-solar-system-s-interstellar-winds
  30. http://www.youtube.com/watch?v=9ZaGqnGn5x4
  31. https://www.science.org/doi/full/10.1126/science.1239925
  32. https://youtu.be/CHhiJoOcInY
  33. https://apod.nasa.gov/apod/ap241221.html
  34. https://apod.nasa.gov/apod/archivepix.html
  35. https://apod.nasa.gov/apod/lib/apsubmit2015.html
  36. https://apod.nasa.gov/apod/lib/aptree.html
  37. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search
  38. https://apod.nasa.gov/apod/calendar/allyears.html
  39. https://apod.com/feed.rss
  40. https://apod.nasa.gov/apod/lib/edlinks.html
  41. https://apod.nasa.gov/apod/lib/about_apod.html
  42. https://asterisk.apod.com/discuss_apod.php?date=241222
  43. https://apod.nasa.gov/apod/ap241223.html
  44. http://www.phy.mtu.edu/faculty/Nemiroff.html
  45. http://www.phy.mtu.edu/
  46. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html
  47. http://www.astro.umd.edu/
  48. https://apod.nasa.gov/apod/lib/about_apod.html#srapply
  49. https://www.nasa.gov/about/highlights/HP_Privacy.html
  50. https://www.nasa.gov/general/accessibility/
  51. https://www.nasa.gov/privacy/
  52. https://astrophysics.gsfc.nasa.gov/
  53. https://www.nasa.gov/
  54. https://www.nasa.gov/centers/goddard/
  55. https://science.nasa.gov/learners
  56. http://www.mtu.edu/