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University-Style Sweatshirt 3XL
$45.00
Orientation week for rising Freshmen includes getting familiar with the layout of the campus, social mixers, and a visit to the college bookstore. There you'll pick up your books, supplies, and probably your university-style sweatshirt. Wearing your school's logo shows your pride in receiving a high-quality education there. This sweatshirt performs the same function! Show your pride that you've learned so much from Crash Course. DETAILS Dark Blue crewneck sweatshirt with Crash Course logo 80/20 Cotton Polyester Blend Show pride in your education! Please note: this item is printed on-demand and will ship within 14 business days of ordering. Your entire order will ship together at this time. Please plan accordingly.
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!
Crash Course - Lifelong Learner Tee L
$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 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
Crash Course - La Célula Animal Póster
$20.00
La célula es la unidad básica de la vida... ¡y es un lugar muy concurrido! Este póster te lleva a un recorrido por una célula animal, desde su membrana celular llena de proteínas hasta sus ribosomas, que trabajan duro. Incluye datos sobre algunos de los animales más increíbles que existen y avances científicos clave que han hecho avanzar nuestro conocimiento sobre las células. DETALLES Impresión vertical de 18" x 24" Papel semibrillante de 100 lb Obra de arte de Thought Cafe para Crash Course
Black Holes: Crash Course Astronomy #33
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2,785,798Views
2015Sep 25
We’ve covered a lot of incredible stuff, but this week we’re talking about the weirdest objects in space: BLACK HOLES. Stellar-mass black holes form when a very massive star dies, and its core collapses. The core has to be more than about 2.8 times the Sun’s mass to form a black hole. Black holes come in different sizes, but for all of them, the escape velocity is greater than the speed of light, so nothing can escape, not matter or light. They don’t wander the Universe gobbling everything down around them; their gravity is only really intense very close to them. Tides near a stellar mass black hole will spaghettify you, and time slows down when you get near a black hole — not that this helps much if you’re falling in. Check out the Crash Course Astronomy solar system poster here: http://store.dftba.com/products/crash... -- Chapters: Introduction 00:00 How Black Holes Are Formed 1:03 Misconceptions About Black Holes 3:05 Stellar Mass Black Holes 5:03 Spaghettification 5:50 Black Holes Warp Space-Time 8:00 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 White Dwarf Pulses Like a Pulsar http://www.nasa.gov/centers/goddard/n... [credit: NASA, Casey Reed] Swift Reveals New Phenomenon in a Neutron Star http://www.nasa.gov/mission_pages/swi... [credit: NASA's Goddard Space Flight Center] Black Holes - Monsters in Space https://en.wikipedia.org/wiki/File:Bl... [credit: NASA/JPL-Caltech, Wikimedia Commons] What if the Sun became a black hole? (artist's impression) http://www.spacetelescope.org/videos/... [credit: ESA/Hubble (M. Kornmesser)] Black Hole Animation http://chandra.harvard.edu/photo/2003... [credit: NASA/SAO/CXC/D.Berry] Star Destroyer http://svs.gsfc.nasa.gov/cgi-bin/deta... [credit: Space Telescope Science Institute (STScI) and NASA's Goddard Space Flight Center] Black hole deforms space http://www.spacetelescope.org/videos/... [credit: ESA/Hubble (M. Kornmesser & L. L. Christensen)] Black hole close-up (artist's impression) http://www.spacetelescope.org/videos/... [credit: European Space Agency, NASA and Felix Mirabel (the French Atomic Energy Commission & the Institute for Astronomy and Space Physics/Conicet of Argentina)]

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