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 | [38]Calendar | [39]RSS | [40]Education | [41]About APOD | [42]Discuss | [43]> __________________________________________________________________ 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/