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. 2025 July 9 [2]See Explanation. Clicking on the picture will download the highest resolution version available. A Beautiful Trifid Image Credit & [3]Copyright: [4]Alessandro Cipolat Bares Explanation: [5]The beautiful Trifid Nebula is a cosmic study in contrasts. [6]Also known as M20, it lies about 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, in this deep telescopic view it almost covers the area of a full moon on planet Earth's sky. Tomorrow's picture: pixels in space __________________________________________________________________ [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: Amber Straughn [28]Specific rights apply. [29]NASA Web Privacy, [30]Accessibility, [31]Notices; A service of: [32]ASD at [33]NASA / [34]GSFC, [35]NASA Science Activation & [36]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2507/Trifid2048.jpg 3. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 4. https://www.flickr.com/photos/astrobares/ 5. https://www.flickr.com/photos/astrobares/53936303451/in/album-72177720319791096 6. https://science.nasa.gov/mission/hubble/science/explore-the-night-sky/hubble-messier-catalog/messier-20/ 7. https://apod.nasa.gov/apod/ap250625.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. https://hubblesite.org/contents/media/images/1999/42/915-Image.html 13. https://apod.nasa.gov/apod/ap250705.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.com/feed.rss 20. https://apod.nasa.gov/apod/lib/edlinks.html 21. https://apod.nasa.gov/apod/lib/about_apod.html 22. https://asterisk.apod.com/discuss_apod.php?date=250706 23. https://apod.nasa.gov/apod/ap250707.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://www.nasa.gov/general/accessibility/ 31. https://www.nasa.gov/privacy/ 32. https://astrophysics.gsfc.nasa.gov/ 33. https://www.nasa.gov/ 34. https://www.nasa.gov/centers/goddard/ 35. https://science.nasa.gov/learners 36. http://www.mtu.edu/