The free-fall contraction of a molecular cloud
A)can be initiated by shock waves from supernovae.
B)can be initiated by nearby spectral type G stars.
C)can be initiated by the rotation of the cloud.
D)causes the cloud to become transparent to ultraviolet radiation.
E)causes the particles in the cloud to decrease the speed with which they move.

Question

Quizplus · Accepted Answer

Shock waves from supernovae can compress the gas in a molecular cloud, initiating its collapse under gravity, leading to star formation.

The Free-Fall Contraction of a Molecular Cloud