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 October 28 [2]See Explanation. Clicking on the picture will download the highest resolution version available. The Ghosts of Gamma Cas Image Credit & [3]Copyright: [4]Guillaume Gruntz, [5]Jean-François Bax Explanation: [6]Gamma Cassiopeiae shines high in northern autumn evening skies. It's the brightest spiky star in this telescopic field of view toward the constellation Cassiopeia. [7]Gamma Cas shares the ethereal-looking scene with ghostly interstellar clouds of gas and dust, IC 59 (top left) and IC 63. About 600 light-years distant, [8]the clouds aren't actually ghosts. They are slowly disappearing though, eroding under the influence of [9]energetic radiation from hot and luminous gamma Cas. [10]Gamma Cas is physically located only 3 to 4 light-years from the nebulae. Slightly closer to gamma Cas, IC 63 is dominated by [11]red H-alpha light emitted as hydrogen atoms ionized by the star's ultraviolet radiation recombine with electrons. Farther from the star, IC 59 shows proportionally less H-alpha emission but more of the characteristic blue tint of dust [12]reflected star light. The cosmic stage spans over 1 degree or 10 light-years at the estimated distance of [13]gamma Cas and friends. Tomorrow's picture: ghosts of the Cepheus Flare __________________________________________________________________ [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/2310/IC63_GruntzBax.jpg 3. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 4. https://www.astrobin.com/users/GuillaumeGz/ 5. https://www.astrobin.com/users/jeffbax/ 6. https://www.aavso.org/vsots_gammacas 7. https://www.astrobin.com/k5f7nk/0/ 8. https://hubblesite.org/contents/news-releases/2018/news-2018-42.html 9. https://arxiv.org/abs/1809.01419 10. https://en.wikipedia.org/wiki/Gamma_Cassiopeiae 11. https://apod.nasa.gov/apod/ap111013.html 12. https://apod.nasa.gov/apod/ap091126.html 13. https://arxiv.org/abs/1705.04313 14. https://apod.nasa.gov/apod/ap231027.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=231028 24. https://apod.nasa.gov/apod/ap231029.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/