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. 2022 August 5 [2]See Explanation. Clicking on the picture will download the highest resolution version available. A Beautiful Trifid Image Credit & [3]Copyright: [4]Vikas Chander Explanation: The beautiful Trifid Nebula is a cosmic [5]study in contrasts. Also known as M20, it lies about [6]5,000 light-years away toward the [7]nebula rich constellation Sagittarius. A star forming region in the plane of our galaxy, the Trifid does illustrate three different types of astronomical nebulae; red [8]emission nebulae dominated by light from hydrogen atoms, blue [9]reflection nebulae produced by dust reflecting starlight, and [10]dark nebulae where dense dust clouds appear in silhouette. But the red emission region, roughly separated into three parts by obscuring dust lanes, is what lends the Trifid its [11]popular name. Pillars and jets sculpted by newborn stars, above and right of the emission nebula's center, appear in famous Hubble Space Telescope [12]close-up images of the region. The Trifid Nebula is about 40 light-years across. Too faint to be seen by the unaided eye, it almost covers the area of a full moon in planet Earth's sky. Open star cluster M21 just peeks into this telescopic field of view along the bottom right edge of the frame. Tomorrow's picture: the grooved moon of Mars __________________________________________________________________ [13]< | [14]Archive | [15]Submissions | [16]Index | [17]Search | [18]Calendar | [19]RSS | [20]Education | [21]About APOD | [22]Discuss | [23]> __________________________________________________________________ Authors & editors: [24]Robert Nemiroff ([25]MTU) & [26]Jerry Bonnell ([27]UMCP) NASA Official: Phillip Newman [28]Specific rights apply. [29]NASA Web Privacy Policy and Important Notices A service of: [30]ASD at [31]NASA / [32]GSFC, [33]NASA Science Activation & [34]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2208/M20-Trifid-Nebula-4096.jpg 3. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 4. https://www.vikaschander.com/ 5. http://www.messier.seds.org/m/m020.html 6. http://www.atlasoftheuniverse.com/5000lys.html 7. https://apod.nasa.gov/apod/ap130712.html 8. https://apod.nasa.gov/apod/ap080424.html 9. https://apod.nasa.gov/apod/ap090521.html 10. https://apod.nasa.gov/apod/ap090522.html 11. http://en.wikipedia.org/wiki/Trifid_Nebula 12. http://hubblesite.org/image/915/news_release/1999-42 13. https://apod.nasa.gov/apod/ap220804.html 14. https://apod.nasa.gov/apod/archivepix.html 15. https://apod.nasa.gov/apod/lib/apsubmit2015.html 16. https://apod.nasa.gov/apod/lib/aptree.html 17. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 18. https://apod.nasa.gov/apod/calendar/allyears.html 19. https://apod.nasa.gov/apod.rss 20. https://apod.nasa.gov/apod/lib/edlinks.html 21. https://apod.nasa.gov/apod/lib/about_apod.html 22. http://asterisk.apod.com/discuss_apod.php?date=220805 23. https://apod.nasa.gov/apod/ap220806.html 24. http://www.phy.mtu.edu/faculty/Nemiroff.html 25. http://www.phy.mtu.edu/ 26. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 27. http://www.astro.umd.edu/ 28. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 29. https://www.nasa.gov/about/highlights/HP_Privacy.html 30. https://astrophysics.gsfc.nasa.gov/ 31. https://www.nasa.gov/ 32. https://www.nasa.gov/centers/goddard/ 33. https://science.nasa.gov/learners 34. http://www.mtu.edu/