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 August 18 [2]The picture shows a wide field image M57, the Ring Nebula, showing several outer rings not normally seen. Please see the explanation for more detailed information. Rings Around the Ring Nebula Image Credit: [3]Hubble, [4]Large Binocular Telescope, [5]Subaru Telescope; Composition & Copyright: [6]Robert Gendler Explanation: The [7]Ring Nebula (M57), is more complicated than it appears through a small telescope. The easily visible [8]central ring is about one [9]light-year across, but [10]this remarkably deep exposure - a collaborative effort combining data from three different large telescopes - [11]explores the looping filaments of glowing gas extending much farther from [12]the nebula's central star. This [13]composite image includes red light emitted by hydrogen as well as visible and [14]infrared light. The Ring Nebula is an elongated [15]planetary nebula, a type of nebula created when a [16]Sun-like star evolves to [17]throw off its outer atmosphere to become a [18]white dwarf star. The [19]Ring Nebula is about 2,500 light-years away toward the musical [20]constellation Lyra. Amateur Astronomers: Please take the [21]Night Sky Network's Survey Tomorrow's picture: pixels in space dust __________________________________________________________________ [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/2108/M57Ring_HubbleGendler_3000.jpg 3. https://hla.stsci.edu/ 4. http://www.lbto.org/ 5. https://subarutelescope.org/en/ 6. http://www.robgendlerastropics.com/Biography2.html 7. https://en.wikipedia.org/wiki/Ring_nebula 8. https://apod.nasa.gov/apod/ap210815.html 9. http://chandra.harvard.edu/photo/cosmic_distance.html 10. http://www.robgendlerastropics.com/M57-HST-LBT.html 11. http://arxiv.org/abs/astro-ph/0401056 12. https://apod.nasa.gov/apod/ap210721.html 13. http://www.robgendlerastropics.com/M57-HST-LBT.html 14. https://science.nasa.gov/ems/07_infraredwaves 15. https://astronomy.swin.edu.au/cosmos/p/Planetary+Nebulae 16. https://apod.nasa.gov/apod/ap180926.html 17. https://www.youtube.com/watch?v=6FSIfUYFeTM 18. https://imagine.gsfc.nasa.gov/science/objects/dwarfs2.html 19. https://www.youtube.com/watch?v=OiYRL3HFULU 20. http://www.hawastsoc.org/deepsky/lyr/index.html 21. http://bit.ly/astrosurvey2021 22. https://apod.nasa.gov/apod/ap210817.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=210818 32. https://apod.nasa.gov/apod/ap210819.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/