¿ 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 30 [2]See Explanation. Clicking on the picture will download the highest resolution version available. NGC 6357: Cathedral to Massive Stars Image Credit: [3]NASA, [4]ESA and Jesús Maíz Apellániz ([5]IAA, Spain); Acknowledgement: Davide De Martin ([6]ESA/Hubble) Explanation: How massive can a normal star be? Estimates made from distance, brightness and standard [7]solar models had given one star in the [8]open cluster Pismis 24 over 200 times the mass of our [9]Sun, making it one of the most massive stars known. This [10]star is the brightest object [11]located just above the gas front in the [12]featured image. Close inspection of [13]images taken with the [14]Hubble Space Telescope, however, have shown that Pismis 24-1 derives its brilliant luminosity [15]not from a single star but from [16]three at least. [17]Component stars would still remain near 100 solar masses, making them among the more [18]massive stars currently on record. Toward the bottom of the image, [19]stars are still forming in the associated [20]emission nebula [21]NGC 6357. Appearing perhaps like a [22]Gothic cathedral, energetic stars near the center appear to be [23]breaking out and illuminating a [24]spectacular cocoon. Teachers & Students: [25]Ideas for Utilizing APOD in the Classroom Tomorrow's picture: micro-quasar imagined __________________________________________________________________ [26]< | [27]Archive | [28]Submissions | [29]Index | [30]Search | [31]Calendar | [32]RSS | [33]Education | [34]About APOD | [35]Discuss | [36]> __________________________________________________________________ Authors & editors: [37]Robert Nemiroff ([38]MTU) & [39]Jerry Bonnell ([40]UMCP) NASA Official: Phillip Newman [41]Specific rights apply. [42]NASA Web Privacy Policy and Important Notices A service of: [43]ASD at [44]NASA / [45]GSFC & [46]Michigan Tech. U. References 1. https://apod.nasa.gov/apod/archivepix.html 2. https://apod.nasa.gov/apod/image/2008/ngc6357_hubble_3140.jpg 3. https://www.nasa.gov/ 4. https://www.esa.int/ 5. https://www.iaa.es/ 6. https://www.spacetelescope.org/ 7. http://spiff.rit.edu/classes/phys230/lectures/star_age/star_age.html 8. https://apod.nasa.gov/apod/open_clusters.html 9. https://www.nasa.gov/sun 10. https://science.nasa.gov/astrophysics/focus-areas/how-do-stars-form-and-evolve/ 11. https://www.youtube.com/watch?v=iLbY7PYzku8 12. https://www.spacetelescope.org/news/html/heic0619.html 13. https://hubblesite.org/newscenter/archive/releases/2006/54/image/ 14. https://apod.nasa.gov/apod/ap010806.html 15. https://www.spacetelescope.org/news/heic0619/ 16. https://ui.adsabs.harvard.edu/abs/2007ApJ...660.1480M/abstract 17. https://apod.nasa.gov/apod/ap160205.html 18. https://en.wikipedia.org/wiki/List_of_most_massive_stars 19. http://asterisk.apod.com/viewtopic.php?f=24&t=18010 20. https://apod.nasa.gov/apod/emission_nebulae.html 21. https://apod.nasa.gov/apod/ap081009.html 22. http://upload.wikimedia.org/wikipedia/commons/6/65/Catedral_Metropolitana_de_Sao_Paulo_1_Brasil-edit-01.jpg 23. http://cdn.images.express.co.uk/img/dynamic/1/590x/cat-439127.jpg 24. https://apod.nasa.gov/apod/ap150517.html 25. https://apod.nasa.gov/apod/lib/apodclass.html 26. https://apod.nasa.gov/apod/ap200829.html 27. https://apod.nasa.gov/apod/archivepix.html 28. https://apod.nasa.gov/apod/lib/apsubmit2015.html 29. https://apod.nasa.gov/apod/lib/aptree.html 30. https://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search 31. https://apod.nasa.gov/apod/calendar/allyears.html 32. https://apod.nasa.gov/apod.rss 33. https://apod.nasa.gov/apod/lib/edlinks.html 34. https://apod.nasa.gov/apod/lib/about_apod.html 35. http://asterisk.apod.com/discuss_apod.php?date=200830 36. https://apod.nasa.gov/apod/ap200831.html 37. http://www.phy.mtu.edu/faculty/Nemiroff.html 38. http://www.phy.mtu.edu/ 39. https://antwrp.gsfc.nasa.gov/htmltest/jbonnell/www/bonnell.html 40. http://www.astro.umd.edu/ 41. https://apod.nasa.gov/apod/lib/about_apod.html#srapply 42. https://www.nasa.gov/about/highlights/HP_Privacy.html 43. https://astrophysics.gsfc.nasa.gov/ 44. https://www.nasa.gov/ 45. https://www.nasa.gov/centers/goddard/ 46. http://www.mtu.edu/