¿ 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. 2020 August 25 IFRAME: [2]https://www.youtube.com/embed/l36UkYtq6m0?rel=0 Visualization: A Black Hole Accretion Disk Visualization Credit: [3]NASA's [4]Goddard Space Flight Center, [5]Jeremy Schnittman Explanation: What would it look like to circle a black hole? If the [6]black hole was surrounded by a [7]swirling disk of glowing and accreting gas, then the great gravity of the black hole would [8]deflect light emitted by the disk to make it look very unusual. The [9]featured animated video gives a visualization. The video starts with you, the observer, looking toward the [10]black hole from just above the plane of the accretion disk. Surrounding the central [11]black hole is a thin circular image of the orbiting disk that marks the position of the [12]photon sphere -- inside of which lies the black hole's [13]event horizon. Toward the left, parts of the large main image of the disk [14]appear brighter as they move toward you. As [15]the video continues, you loop over the [16]black hole, soon looking down from the top, then passing through the disk plane on the far side, then returning to your [17]original vantage point. The accretion disk does some interesting [18]image inversions -- but never appears flat. Visualizations such as this are particularly relevant today as [19]black holes are being imaged in unprecedented detail by the [20]Event Horizon Telescope. Tomorrow's picture: swan and galaxy __________________________________________________________________ [21]< | [22]Archive | [23]Submissions | [24]Index | [25]Search | [26]Calendar | [27]RSS | [28]Education | [29]About APOD | [30]Discuss | [31]> __________________________________________________________________ Authors & editors: [32]Robert Nemiroff ([33]MTU) & [34]Jerry Bonnell ([35]UMCP) NASA Official: Phillip Newman [36]Specific rights apply. [37]NASA Web Privacy Policy and Important Notices A service of: [38]ASD at [39]NASA / [40]GSFC & [41]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://www.youtube.com/embed/l36UkYtq6m0?rel=0 3. https://www.nasa.gov/ 4. https://science.gsfc.nasa.gov/sci/ 5. https://science.gsfc.nasa.gov/sed/bio/jeremy.d.schnittman 6. https://science.nasa.gov/astrophysics/focus-areas/black-holes 7. https://apod.nasa.gov/apod/ap190820.html 8. https://www.phy.mtu.edu/bht/rjn_bht.html 9. https://svs.gsfc.nasa.gov/13326 10. https://apod.nasa.gov/apod/ap200324.html 11. https://jila.colorado.edu/hamilton/black-holes/journey-schwarzschild-black-hole 12. https://en.wikipedia.org/wiki/Photon_sphere 13. https://en.wikipedia.org/wiki/Event_horizon 14. https://en.wikipedia.org/wiki/Aberration_(astronomy) 15. https://www.youtube.com/watch?v=l36UkYtq6m0 16. https://ui.adsabs.harvard.edu/abs/1993AmJPh..61..619N/abstract 17. https://apod.nasa.gov/apod/image/2008/BhAccretionDisk_NasaSchnittman_3851_annotated.jpg 18. https://apod.nasa.gov/apod/ap141026.html 19. https://apod.nasa.gov/apod/ap190411.html 20. https://eventhorizontelescope.org/ 21. https://apod.nasa.gov/apod/ap200824.html 22. https://apod.nasa.gov/apod/archivepix.html 23. https://apod.nasa.gov/apod/lib/apsubmit2015.html 24. https://apod.nasa.gov/apod/lib/aptree.html 25. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 26. https://apod.nasa.gov/apod/calendar/allyears.html 27. https://apod.nasa.gov/apod.rss 28. https://apod.nasa.gov/apod/lib/edlinks.html 29. https://apod.nasa.gov/apod/lib/about_apod.html 30. http://asterisk.apod.com/discuss_apod.php?date=200825 31. https://apod.nasa.gov/apod/ap200826.html 32. http://www.phy.mtu.edu/faculty/Nemiroff.html 33. http://www.phy.mtu.edu/ 34. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 35. http://www.astro.umd.edu/ 36. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 37. https://www.nasa.gov/about/highlights/HP_Privacy.html 38. https://astrophysics.gsfc.nasa.gov/ 39. https://www.nasa.gov/ 40. https://www.nasa.gov/centers/goddard/ 41. http://www.mtu.edu/