4.1.1. Formation of a Protostar

In the beginning, the gases in the galaxies were mainly hydrogen with some helium. However, they were at a very low temperature of about, -173°C. Since the gases were very cold, they formed very dense clouds in the galaxies. In addition, the gas cloud was very large, so the gravitational pull between the various gas molecules was quite large. Due to large gravitational force, the gas cloud started contracting as a whole. Ultimately, the gas were compressed so much that they formed a highly condensed object called a protostar. A protostar looks a like a

huge, dark, ball of gas. The formation of protostar is only a stage in the formation of complete star. A protostar does not emit light. The next stage consists in the transformation of this highly condensed object called protostar into a star which emits light.