﻿ 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 January 3 [2]A spiral galaxy with big blue spiral arms is shown with a center that appears more yellow. Please see the explanation for more detailed information. NGC 1232: A Grand Design Spiral Galaxy Image Credit: [3]FORS, [4]8.2-meter VLT Antu, [5]ESO Explanation: [6]Galaxies are fascinating not only for what is visible, but for what is invisible. [7]Grand spiral galaxy [8]NGC 1232, [9]captured in detail by one of the [10]Very Large Telescopes, is a good example. The visible is dominated by millions of [11]bright stars and dark [12]dust, caught up in a gravitational swirl of spiral arms revolving about the center. [13]Open clusters containing bright blue stars can be seen sprinkled along these spiral arms, while [14]dark lanes of dense interstellar [15]dust can be seen sprinkled between them. [16]Less visible, but detectable, are billions of dim normal stars and vast tracts of [17]interstellar gas, together wielding such high mass that they dominate the dynamics of the inner [18]galaxy. Leading theories indicate that even [19]greater amounts of matter are invisible, in a form we don't yet know. This pervasive [20]dark matter is postulated, in part, to explain the [21]motions of the visible matter in the outer regions of galaxies. Free APOD Lecture: [22]January 9, 2024 to the Amateur Astronomers of Association of New York Tomorrow's picture: open space __________________________________________________________________ [23]< | [24]Archive | [25]Submissions | [26]Index | [27]Search | [28]Calendar | [29]RSS | [30]Education | [31]About APOD | [32]Discuss | [33]> __________________________________________________________________ Authors & editors: [34]Robert Nemiroff ([35]MTU) & [36]Jerry Bonnell ([37]UMCP) NASA Official: Phillip Newman [38]Specific rights apply. [39]NASA Web Privacy Policy and Important Notices A service of: [40]ASD at [41]NASA / [42]GSFC, [43]NASA Science Activation & [44]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2401/ngc1232b_vlt_3969.jpg 3. https://www.eso.org/sci/facilities/paranal/instruments/fors/ 4. https://www.eso.org/projects/vlt/ 5. https://www.eso.org/ 6. https://pages.astronomy.ua.edu/keel/galaxies/ 7. https://apod.nasa.gov/apod/ap961030.html 8. https://ui.adsabs.harvard.edu/abs/1997AAS...191.8203B/abstract 9. https://www.eso.org/public/images/eso9845d/ 10. https://apod.nasa.gov/apod/ap000707.html 11. https://apod.nasa.gov/apod/ap221205.html 12. https://apod.nasa.gov/apod/ap030706.html 13. https://apod.nasa.gov/apod/open_clusters.html 14. https://apod.nasa.gov/apod/ap980116.html 15. https://apod.nasa.gov/apod/ap001119.html 16. https://files.ctctcdn.com/3a7f39ae001/aedd7697-f09f-4b3a-8f7b-256d0a0389bc.jpg 17. https://apod.nasa.gov/apod/ap010113.html 18. https://asterisk.apod.com/viewtopic.php?f=24&t=18005 19. https://apod.nasa.gov/apod/ap031231.html 20. https://chandra.harvard.edu/xray_astro/dark_matter.html 21. https://en.wikipedia.org/wiki/Dark_matter 22. https://aaa.org/event/2023-astronomy-picture-of-the-day/ 23. https://apod.nasa.gov/apod/ap231231.html 24. https://apod.nasa.gov/apod/archivepix.html 25. https://apod.nasa.gov/apod/lib/apsubmit2015.html 26. https://apod.nasa.gov/apod/lib/aptree.html 27. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 28. https://apod.nasa.gov/apod/calendar/allyears.html 29. https://apod.com/feed.rss 30. https://apod.nasa.gov/apod/lib/edlinks.html 31. https://apod.nasa.gov/apod/lib/about_apod.html 32. https://asterisk.apod.com/discuss_apod.php?date=240101 33. https://apod.nasa.gov/apod/ap240102.html 34. http://www.phy.mtu.edu/faculty/Nemiroff.html 35. http://www.phy.mtu.edu/ 36. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 37. http://www.astro.umd.edu/ 38. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 39. https://www.nasa.gov/about/highlights/HP_Privacy.html 40. https://astrophysics.gsfc.nasa.gov/ 41. https://www.nasa.gov/ 42. https://www.nasa.gov/centers/goddard/ 43. https://science.nasa.gov/learners 44. http://www.mtu.edu/