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.

                                 2023 June 1
    [2]See Explanation. Clicking on the picture will download the highest
                        resolution version available.

                           Recycling Cassiopeia A
     Image Credit: X-ray - [3]NASA, [4]CXC, SAO; Optical - [5]NASA,STScI

   Explanation: Massive stars in our Milky Way Galaxy live spectacular
   lives. Collapsing from vast cosmic clouds, their nuclear furnaces
   ignite and create heavy elements in their cores. After a few million
   years, the [6]enriched material is blasted back into interstellar space
   where star formation can begin anew. The expanding debris cloud known
   as Cassiopeia A is an example of this final phase of the stellar life
   cycle. Light from the explosion which created this supernova remnant
   would have been first [7]seen in planet Earth's sky about 350 years
   ago, although it took that light about 11,000 years to reach us.
   [8]This false-color image, composed of X-ray and optical image data
   from the Chandra X-ray Observatory and Hubble Space Telescope, shows
   the still hot filaments and knots in the remnant. It spans about 30
   light-years at the estimated distance of Cassiopeia A. High-energy
   X-ray emission from specific elements has been color coded, silicon in
   red, sulfur in yellow, calcium in green and iron in purple, to help
   [9]astronomers explore the recycling of our galaxy's [10]star stuff.
   Still expanding, the outer blast wave is seen in blue hues. [11]The
   bright speck near the center is a neutron star, the incredibly dense,
   collapsed remains of the massive stellar core.

                     Tomorrow's picture: massive galaxy
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    Authors & editors: [23]Robert Nemiroff ([24]MTU) & [25]Jerry Bonnell
                                 ([26]UMCP)
          NASA Official: Phillip Newman [27]Specific rights apply.
              [28]NASA Web Privacy Policy and Important Notices
                A service of: [29]ASD at [30]NASA / [31]GSFC
                           & [32]Michigan Tech. U.

References

   1. https://apod.nasa.gov/apod/archivepix.html
   2. https://apod.nasa.gov/apod/image/2306/Chandrafirstlight_0.jpg
   3. https://www.nasa.gov/
   4. http://chandra.harvard.edu/
   5. http://www.stsci.edu/
   6. https://apod.nasa.gov/apod/ap190801.html
   7. https://spider.seds.org/spider/Vars/casA.html
   8. https://www.nasa.gov/mission_pages/chandra/images/the-latest-look-at-first-light-from-chandra.html
   9. https://arxiv.org/abs/1111.7316
  10. https://apod.nasa.gov/apod/ap171119.html
  11. https://apod.nasa.gov/apod/ap170501.html
  12. https://apod.nasa.gov/apod/ap230531.html
  13. https://apod.nasa.gov/apod/archivepix.html
  14. https://apod.nasa.gov/apod/lib/apsubmit2015.html
  15. https://apod.nasa.gov/apod/lib/aptree.html
  16. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search
  17. https://apod.nasa.gov/apod/calendar/allyears.html
  18. https://apod.nasa.gov/apod.rss
  19. https://apod.nasa.gov/apod/lib/edlinks.html
  20. https://apod.nasa.gov/apod/lib/about_apod.html
  21. http://asterisk.apod.com/discuss_apod.php?date=230601
  22. https://apod.nasa.gov/apod/ap230602.html
  23. http://www.phy.mtu.edu/faculty/Nemiroff.html
  24. http://www.phy.mtu.edu/
  25. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html
  26. http://www.astro.umd.edu/
  27. https://apod.nasa.gov/apod/lib/about_apod.html#srapply
  28. https://www.nasa.gov/about/highlights/HP_Privacy.html
  29. https://astrophysics.gsfc.nasa.gov/
  30. https://www.nasa.gov/
  31. https://www.nasa.gov/centers/goddard/
  32. http://www.mtu.edu/