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Science and Nature

Crash Course Astronomy

Black Holes: Crash Course Astronomy #33

Welcome to school without the classroom! Join host Phil Plait and discover everything there is to know about the cosmos.

Black Holes: Crash Course Astronomy #33

Season 1 Episode 33 | 12m 11s

Stellar mass black holes form when a very massive star dies, and its core collapses. 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.

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Crash Course Astronomy

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