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 July 29 [2]See Explanation. Clicking on the picture will download the highest resolution version available. The Tulip and Cygnus X-1 Image Credit & [3]Copyright: [4]Carlos Uriarte Explanation: [5]This tall telescopic field of view looks out along the plane of our Milky Way Galaxy toward the nebula rich constellation [6]Cygnus the Swan. Popularly called the Tulip Nebula, the brightest glowing cloud of interstellar gas and dust above center is also found in the [7]1959 catalog by astronomer Stewart Sharpless [8]as Sh2-101. Nearly 70 light-years across the complex and beautiful Tulip Nebula blossoms about 8,000 light-years away, shown in a Hubble palette image that maps the glow of the nebula's sulfur, hydrogen, and oxygen ions into red, green, and blue colors. Ultraviolet radiation from young energetic stars at the edge of the Cygnus [9]OB3 association, including [10]O star HDE 227018, [11]ionizes the atoms and powers the emission from the Tulip Nebula. Also in the field of view is microquasar [12]Cygnus X-1, one of the strongest X-ray sources in planet Earth's sky. Driven by powerful jets from a black hole accretion disk, its fainter bluish curved shock front is only just visible though, directly [13]above the cosmic Tulip's petals near the top of the frame. Tomorrow's picture: Saturnshine __________________________________________________________________ [14]< | [15]Archive | [16]Submissions | [17]Index | [18]Search | [19]Calendar | [20]RSS | [21]Education | [22]About APOD | [23]Discuss | [24]> __________________________________________________________________ Authors & editors: [25]Robert Nemiroff ([26]MTU) & [27]Jerry Bonnell ([28]UMCP) NASA Official: Phillip Newman [29]Specific rights apply. [30]NASA Web Privacy Policy and Important Notices A service of: [31]ASD at [32]NASA / [33]GSFC & [34]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2107/sh2_101_04.jpg 3. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 4. https://www.flickr.com/people/187879001@N05/ 5. https://www.flickr.com/photos/187879001@N05/51319579978/in/photostream/ 6. http://en.wikipedia.org/wiki/Cygnus_(constellation) 7. http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1959ApJS....4..257S 8. http://galaxymap.org/cat/list/sharpless/101 9. http://en.wikipedia.org/wiki/Stellar_kinematics#OB_associations 10. https://apod.nasa.gov/apod/ap070726.html 11. https://apod.nasa.gov/apod/ap111103.html 12. http://chandra.harvard.edu/photo/2011/cygx1/ 13. https://apod.nasa.gov/apod/ap090608.html 14. https://apod.nasa.gov/apod/ap210728.html 15. https://apod.nasa.gov/apod/archivepix.html 16. https://apod.nasa.gov/apod/lib/apsubmit2015.html 17. https://apod.nasa.gov/apod/lib/aptree.html 18. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 19. https://apod.nasa.gov/apod/calendar/allyears.html 20. https://apod.nasa.gov/apod.rss 21. https://apod.nasa.gov/apod/lib/edlinks.html 22. https://apod.nasa.gov/apod/lib/about_apod.html 23. http://asterisk.apod.com/discuss_apod.php?date=210729 24. https://apod.nasa.gov/apod/ap210730.html 25. http://www.phy.mtu.edu/faculty/Nemiroff.html 26. http://www.phy.mtu.edu/ 27. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 28. http://www.astro.umd.edu/ 29. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 30. https://www.nasa.gov/about/highlights/HP_Privacy.html 31. https://astrophysics.gsfc.nasa.gov/ 32. https://www.nasa.gov/ 33. https://www.nasa.gov/centers/goddard/ 34. http://www.mtu.edu/