﻿ 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 June 30 IFRAME: [2]https://www.youtube.com/embed/q9ZCBR-onRw?rel=0 Simulation: Formation of the First Stars Video Credit: [3]Harley Katz ([4]U. Oxford) [5]et al. Explanation: How did the first stars form? To help find out, the SPHINX computer simulation of [6]star formation in the very early universe was created, some results of which are shown in the [7]featured video. Time since the [8]Big Bang is shown in millions of years on the upper left. Even 100 million years after the [9]Big Bang, matter was spread [10]too uniformly across the cosmos for stars to be born. Besides [11]background radiation, the universe was dark. Soon, slight matter clumps rich in [12]hydrogen gas begin to coalesce into the [13]first stars. In the [14]time-lapse video, purple denotes gas, white denotes light, and gold shows radiation so energetic that it [15]ionizes hydrogen, breaking it up into charged electrons and protons. The gold-colored regions also track the most massive stars that die with [16]powerful supernovas. The inset circle highlights a central region that is [17]becoming a galaxy. The simulation continues until the universe was about 550 million years old. To assess the accuracy of the [18]SPHINX simulations and the assumptions that went into them, the results are not only being [19]compared to current deep observations, but will also be compared with [20]more direct observations of the early universe planned with NASA's pending [21]James Web Space Telescope. Tomorrow's picture: open space __________________________________________________________________ [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://www.youtube.com/embed/q9ZCBR-onRw?rel=0 3. https://www.physics.ox.ac.uk/our-people/katz 4. https://www.physics.ox.ac.uk/ 5. https://academic.oup.com/mnras/article-abstract/487/4/5902/5520831 6. https://apod.nasa.gov/apod/ap210623.html 7. https://youtu.be/q9ZCBR-onRw 8. https://science.nasa.gov/astrophysics/focus-areas/what-powered-the-big-bang 9. https://www.jwst.nasa.gov/content/features/bigBangQandA.html 10. https://static.onecms.io/wp-content/uploads/sites/20/2018/05/21042210_264995290674140_8840525631411191808_n.jpg 11. https://apod.nasa.gov/apod/ap180722.html 12. https://periodic.lanl.gov/1.shtml 13. https://www.scientificamerican.com/article/the-first-stars-in-the-un/ 14. https://youtu.be/BLnsYXEL1B0 15. https://en.wikipedia.org/wiki/Ionization 16. https://youtu.be/aysiMbgml5g 17. https://www.jwst.nasa.gov/content/science/firstLight.html 18. https://arxiv.org/abs/2101.11624 19. https://ui.adsabs.harvard.edu/abs/2021MNRAS.505.3336L/abstract 20. https://ui.adsabs.harvard.edu/abs/2019MNRAS.487.5902K/abstract 21. https://www.jwst.nasa.gov/ 22. https://apod.nasa.gov/apod/ap210629.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=210630 32. https://apod.nasa.gov/apod/ap210701.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/