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.

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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

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White Dwarf Pulses Like a Pulsar http://www.nasa.gov/centers/goddard/news/topstory/2007/whitedwarf_pulsar.html [credit: NASA, Casey Reed]
Swift Reveals New Phenomenon in a Neutron Star http://www.nasa.gov/mission_pages/swift/bursts/new-phenom.html#.Vc4isflVhBd [credit: NASA’s Goddard Space Flight Center]
Black Holes – Monsters in Space https://en.wikipedia.org/wiki/File:Black_Holes_-_Monsters_in_Space.jpg [credit: NASA/JPL-Caltech, Wikimedia Commons]
What if the Sun became a black hole? (artist’s impression) http://www.spacetelescope.org/videos/hubblecast43g/ [credit: ESA/Hubble (M. Kornmesser)]
Black Hole Animation http://chandra.harvard.edu/photo/2003/0203long/animations.html [credit: NASA/SAO/CXC/D.Berry]
Star Destroyer http://svs.gsfc.nasa.gov/cgi-bin/details.cgi?aid=11065 [credit: Space Telescope Science Institute (STScI) and NASA’s Goddard Space Flight Center]
Black hole deforms space http://www.spacetelescope.org/videos/hst15_blackhole_grid/ [credit: ESA/Hubble (M. Kornmesser & L. L. Christensen)]
Black hole close-up (artist’s impression) http://www.spacetelescope.org/videos/heic0211c/ [credit: European Space Agency, NASA and Felix Mirabel (the French Atomic Energy Commission & the Institute for Astronomy and Space Physics/Conicet of Argentina)]