The Cosmic Lasers That Form in Outer Space

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Lasers are incredible narrow beams of light we can use to do everything from cutting metal to operating on people's eyeballs. But even though we came up with the idea on our own, humans didn’t actually make the first lasers.

Host: Hank Green

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Sources:
https://www.nasa.gov/home/hqnews/1995/95-148.txt
http://web.ihep.su/dbserv/compas/src/einstein17/eng.pdf
https://lasers.llnl.gov/education/how_lasers_work
https://spaceplace.nasa.gov/laser/en/
http://laserstars.org/history/masers.html
http://laserstars.org/history/hydroxyl.html
https://press.uchicago.edu/Misc/Chicago/284158_townes.html
https://www.nature.com/articles/187493a0
https://www.rp-photonics.com/optical_pumping.html
https://spie.org/news/photonics-focus/janfeb-2020/astrophysical-lasers?SSO=1
https://www.eso.org/sci/facilities/eelt/owl/Files/publications/OWL-CSR-ESO-00000-0162_iss1.pdf
https://apod.nasa.gov/apod/ap960111.html
https://www.nasa.gov/home/hqnews/1995/95-148.txt
https://www.haystack.mit.edu/ast/science/stars/index.html
https://www.nature.com/articles/306640a0
https://www.jstor.org/stable/1353849?seq=1
https://phys.org/news/2012-12-masers-stellar-nurseries.html
https://arxiv.org/pdf/1204.1059.pdf
http://sait.oat.ts.astro.it/MSAIt890318/PDF/2018MmSAI..89..413C.pdf
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Images:
https://www.videoblocks.com/video/cnc-laser-cutting-of-metal-modern-industrial-technology-buhxnbwemjhyq2g6f
https://www.spacetelescope.org/images/heic0601a/
https://commons.wikimedia.org/wiki/File:Einstein_1921_by_F_Schmutzer_-_restoration.jpg
https://commons.wikimedia.org/wiki/File:Orion_Nebula_MPG_ESO_2.2-metre_telescope_at_the_La_Silla_Observatory.jpg
https://www.istockphoto.com/photo/orion-nebula-gm1041379878-278808618
https://en.wikipedia.org/wiki/File:IC_443.jpg
https://www.spacetelescope.org/images/heic1912a/
https://www.spacetelescope.org/images/potw1439a/
https://www.spacetelescope.org/videos/heic0707b/
https://photojournal.jpl.nasa.gov/catalog/PIA13930