What causes clouds of dust and gas to form protostar

Stars form in cold, dense regions of space called molecular clouds. When the force of gravity pulling in on the cloud is greater than the strength of internal pressure pushing out, the cloud collapses into a protostar.

Stars are formed from massive clouds of dust and gas in space. Gravity pulls the dust and gas together to form a protostar. ... The outward pressure from the expanding hot gases is balanced by the force of the star's gravity. 

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