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Crash Course Composition Notebooks - 3 Pack
$10.00
This set of 3 composition notebooks is a great way for you to continue your journey towards being a lifelong learner, as well as a great way to support Crash Course! 100 pages each, college ruled, featuring interior artwork, diagrams, and facts only Crash Course can provide!
2025 Complexly Calendar
$5.00
This year’s calendar celebrates a quarter century of progress, and it is a collaboration between all of your favorite Complexly YouTube channels! Available now!
Crash Course - Lifelong Learner Tee
$32.00
I found myself surrounded by people who celebrated intellectualism and engagement, and who thought that my ironic oh-so-cool disengagement wasn’t clever, or funny. It was a simple and unspectacular response to very complicated and compelling problems. And so I started to learn, because learning was cool. - John Green
Crash Course Pods: Universe - Polo Hat
Limited stock
Dr. Katie Mack, a theoretical astrophysicist, walks #1 New York Times bestselling author John Green through the history of the entire universe - including the parts that haven’t been written yet. Watching the video for this podcast, you may notice a couple of glowing stars that represent each of our hosts. We loved how those stars represented our show so much, we embroidered them on an everyday dad-hat. Now you can contemplate the very nature of existence, take comfort in our relatively insignificant place in our universe, and look sharp-as-heck in the process. DETAILS Low profile "dad-hat" 100% cotton Black with white embroidery One size fits most.
Crash Course Animal Cell Poster
$20.00
The cell is the basic unit of life--and it's one busy place! This poster takes you on a tour of an animal cell, from its protein-studded cell membrane to its hard-working ribosomes. It includes facts about some of the most incredible animals around and key scientific leaps that have advanced our knowledge of cells. DETAILS 18"x24" Portrait Print 100lb Semi Gloss paper Artwork by Thought Cafe for Crash Course
Crash Course Plant Cell Poster
$20.00
Journey into the gravity-defying, sunlight-harvesting world of a plant cell. This poster takes you on a tour of what's beneath the cell wall, teaches you amazing plant facts, and introduces you to key leaps in our understanding of the basic unit of life. DETAILS 18"x24" Portrait Print 100lb Semi Gloss paper Artwork by Thought Cafe for Crash Course
Low Mass Stars: Crash Course Astronomy #29
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1,400,185Views
2015Aug 20
Today we are talking about the life -- and death -- of stars. Low-mass stars live a long time, fusing all their hydrogen into helium over a trillion years. More massive stars like the Sun live shorter lives. They fuse hydrogen into helium, and eventually helium into carbon (and also some oxygen and neon). When this happens they expand, get brighter, and cool off, becoming red giants. They lose most of their mass, exposing their cores, and then cool off over many billions of years. Check out the Crash Course Astronomy solar system poster here: http://store.dftba.com/products/crash... -- Chapters: Introduction: Low Mass Stars 00:00 Hydrogen Fusion 1:21 Life Cycle of Low Mass Stars 2:22 Larger Stars (Like Our Sun) Live Shorter Lives 3:10 Fueled By Fusion 3:58 Red Giants 5:45 White Dwarfs 8:08 The Fate of the Earth 8:59 Review 11:07 -- PBS Digital Studios:    / pbsdigitalstudios   Follow Phil on Twitter:   / badastronomer   Want to find Crash Course elsewhere on the internet? Facebook -   / youtubecrashcourse   Twitter -   / thecrashcourse   Tumblr -   / thecrashcourse   Support CrashCourse on Patreon:   / crashcourse   -- PHOTOS/VIDEOS Stars http://skycenter.arizona.edu/sites/sk... [credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona] The Sizes of Stars http://www.eso.org/public/usa/images/... [credit: ESO/M. Kornmesser] Fusion in the Sun https://commons.wikimedia.org/wiki/Fi... [credit: Borb, Wikimedia Commons] Mega Flares http://scitechdaily.com/images/Swift-... [credit: NASA’s Goddard Space Flight Center/S. Wiessinger] Proxima Centauri https://www.spacetelescope.org/images... [credit: ESA/Hubble & NASA] Physics in the Core http://solarscience.msfc.nasa.gov/ima... [credit: NASA / Marshall Space Flight Center] Three Years of SDO Images http://svs.gsfc.nasa.gov/cgi-bin/deta... [credit: NASA's Goddard Space Flight Center/SDO] Sun & Red Giants http://kepler.nasa.gov/files/mws/kasc... [credit: NASA] Sun as Red Giant https://commons.wikimedia.org/wiki/Fi... [credit:Oona Räisänen, Wikimedia Commons] Gone with the Wind https://www.eso.org/public/usa/images... [credit: ESO] Expanding & cooling https://www.cfa.harvard.edu/sites/www... [credit: ESO/L. Calçada] Looking down a barrel of gas at a doomed star http://hubblesite.org/newscenter/arch... [credit: The Hubble Heritage Team (AURA/STScI/NASA)] Expanding star orbit http://www.nasa.gov/centers/goddard/i... [credit: SO/L. Calçada] Red Giant Earth https://commons.wikimedia.org/wiki/Fi... [credit: Fsgregs, Wikimedia Commons] Crab Nebula https://en.wikipedia.org/wiki/Crab_Ne... [credit: NASA, ESA, J. Hester and A. Loll (Arizona State University)]

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