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Science and Nature
Crash Course Astronomy

Comets: Crash Course Astronomy #21

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

Comets: Crash Course Astronomy #21

Season 1 Episode 21 | 11m 54s

Today on Crash Course Astronomy, Phil explains comets. Comets are chunks of ice and rock that orbit the Sun. When they get near the Sun the ice turns into gas, forming the long tail, and also releases dust that forms a different tail. We've visited comets up close and found them to be lumpy, with vents in the surface that release the gas as ice sublimates.

Crash Course Astronomy

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