What is the primary source of energy for a protostar before nuclear fusion begins in its core?

Answer

Gravitational contraction

During the protostar phase, the object generates energy solely from the conversion of gravitational potential energy as the core continues to collapse and heat up.

What is the primary source of energy for a protostar before nuclear fusion begins in its core?

#Videos

Birth of a star - from nebula to main sequence - YouTube

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