AST-307beginner

Protostars & Pre-Main-Sequence Evolution: Structures & Vocabulary

A protostar is a contracting stellar embryo that has not yet reached long-term hydrogen fusion in its core. Pre-main-sequence evolution connects cloud collapse to mature stars and planet-forming disks.

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beginner40 minFact checked

Protostars & Pre-Main-Sequence Evolution: Structures & Vocabulary

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AST-306Protostars & Pre-Main-Sequence Evolution: Foundations→

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AST-308Protostars & Pre-Main-Sequence Evolution: Physical Mechanisms→

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A protostar is a contracting stellar embryo that has not yet reached long-term hydrogen fusion in its core.

supported

Accreting gas releases gravitational potential energy as heat.

supported

Infrared surveys detect deeply embedded young stellar objects, while jets produce Herbig-Haro shocks where fast outflows collide with ambient gas.