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Nebulae: Crash Course Astronomy #36
Key Facts In This Video
Nebulae are clouds of gas and/or dust in space. They're literally part of the births, lives, and deaths of stars. 00:35
When astronomers refer to dust, they mean tiny grains 1 micron across -- 100 times smaller than a human hair. 02:54
Molecular clouds are cold enough for atoms to stick together to form molecules, with cores that can be hundreds of degrees below zero Celsius. 04:42