Stars

The giant clouds of gas and dust, called nebula are the sites of star formation. The stellar formation, as the star formation is referred to, is due to compression waves which travel around the galaxy, or the shock waves from the supernova explosion.

Eventually the pro-star starts in its center and it begin its independent existence as a true star. It is now called a T. Taurus type star and release energy produced as a result of nuclear fusion. The rest of the clouds are blown away. Most stars, like the sun, spend their life quietly converting hydrogen to helium in its core. The pressure at the center keeps the star expanded. This is a stable period in a star’s life. It is called main sequence star. The star’s luminosity increase, i.e., it gives out more energy as its core becomes denser and hotter.