Second stage of the life cycle of a star is _____.

The correct answer is: Protostar

• A protostar is a very young star that is still gathering mass from its parent molecular cloud.
• The protostellar phase is the earliest one in the process of stellar evolution.
• For a low-mass star (i.e. that of the Sun or lower), it lasts about 500,000 years.
• The stars shine steadily until the hydrogen has fused to form helium ( it takes billions of years in a small star, but only millions in a massive star). Stage 2 - The massive star then becomes a Red Supergiant and starts of with a helium core surrounded by a shell of cooling, expanding gas.