﻿ 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. 2021 September 8 [2]The picture shows a deep wide field image surrounding the Andromeda galaxy M31). Please see the explanation for more detailed information. The Deep Sky Toward Andromeda Image Credit & [3]License: [4]Stefan Ziegenbalg Explanation: What surrounds the Andromeda galaxy? Out in space, [5]Andromeda (M31) is closely surrounded by several small [6]satellite galaxies, and further out it is part of the [7]Local Group of Galaxies -- of which our Milky Way galaxy is also a member. On the sky, however, gas clouds local to [8]our Milky Way appear to surround M31 -- not unlike how water clouds in [9]Earth's atmosphere may appear to [10]encompass our Moon. The [11]gas clouds toward Andromeda, however, are usually too faint to see. Enter the [12]featured 45-degree long image -- one of the deeper images yet taken of the [13]broader Andromeda region. This image, sensitive to light specifically [14]emitted by hydrogen gas, shows these faint and unfamiliar clouds in [15]tremendous detail. But the image captures more. At the image top is the [16]Triangulum galaxy ([17]M33), the third largest galaxy in the [18]Local Group and the furthest object that can be seen with the unaided eye. Below M33 is the bright Milky-Way star [19]Mirach. The image is the digital accumulation of several long exposures taken from 2018 to 2021 from [20]Pulsnitz, [21]Germany. Tomorrow's picture: open space __________________________________________________________________ [22]< | [23]Archive | [24]Submissions | [25]Index | [26]Search | [27]Calendar | [28]RSS | [29]Education | [30]About APOD | [31]Discuss | [32]> __________________________________________________________________ Authors & editors: [33]Robert Nemiroff ([34]MTU) & [35]Jerry Bonnell ([36]UMCP) NASA Official: Phillip Newman [37]Specific rights apply. [38]NASA Web Privacy Policy and Important Notices A service of: [39]ASD at [40]NASA / [41]GSFC & [42]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2109/M31WideField_Ziegenbalg_1400.jpg 3. https://creativecommons.org/licenses/by-nc-sa/2.0/ 4. http://www.simg.de/ 5. https://en.wikipedia.org/wiki/Andromeda_Galaxy 6. https://en.wikipedia.org/wiki/List_of_Andromeda's_satellite_galaxies 7. https://en.wikipedia.org/wiki/Local_Group#Component_galaxies 8. https://solarsystem.nasa.gov/resources/285/the-milky-way-galaxy/ 9. https://climate.nasa.gov/news/2919/earths-atmosphere-a-multi-layered-cake/ 10. https://apod.nasa.gov/apod/ap210119.html 11. https://apod.nasa.gov/apod/ap170104.html 12. http://www.simg.de/nebulae3/and-lac.html 13. https://apod.nasa.gov/apod/ap170303.html 14. https://en.wikipedia.org/wiki/H-alpha 15. https://image.shutterstock.com/image-photo/wide-eyed-double-dapple-dachshund-260nw-1057810916.jpg 16. https://www.nasa.gov/feature/goddard/2019/messier-33-the-triangulum-galaxy 17. https://apod.nasa.gov/apod/ap191231.html 18. http://www.atlasoftheuniverse.com/localgr.html 19. https://en.wikipedia.org/wiki/Beta_Andromedae 20. https://en.wikipedia.org/wiki/Pulsnitz 21. https://en.wikipedia.org/wiki/Germany 22. https://apod.nasa.gov/apod/ap210907.html 23. https://apod.nasa.gov/apod/archivepix.html 24. https://apod.nasa.gov/apod/lib/apsubmit2015.html 25. https://apod.nasa.gov/apod/lib/aptree.html 26. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 27. https://apod.nasa.gov/apod/calendar/allyears.html 28. https://apod.nasa.gov/apod.rss 29. https://apod.nasa.gov/apod/lib/edlinks.html 30. https://apod.nasa.gov/apod/lib/about_apod.html 31. http://asterisk.apod.com/discuss_apod.php?date=210908 32. https://apod.nasa.gov/apod/ap210909.html 33. http://www.phy.mtu.edu/faculty/Nemiroff.html 34. http://www.phy.mtu.edu/ 35. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 36. http://www.astro.umd.edu/ 37. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 38. https://www.nasa.gov/about/highlights/HP_Privacy.html 39. https://astrophysics.gsfc.nasa.gov/ 40. https://www.nasa.gov/ 41. https://www.nasa.gov/centers/goddard/ 42. http://www.mtu.edu/