What process initiates the gravitational collapse within a molecular cloud segment that leads to star birth?

Answer

Instabilities triggered by a passing density wave or supernova shockwave

Pockets of material within the cloud collapse when instabilities, potentially triggered by a passing density wave or the shockwave from a nearby supernova, cause gravity to overcome internal pressure.

What process initiates the gravitational collapse within a molecular cloud segment that leads to star birth?
galaxiesastronomystar formationopen clusters