Fusion in the depths of the stars

   By 1939, it was determined that the source of stellar energy is taking place in the bosom of the stars fusion. Most stars emit because of their bowels, four protons are connected through a series of milestones in a single alpha particle. This transformation can be two main ways, called proton-proton or pp-cycle, and carbon-nitrogen or the CN-cycle. In the low energy stars are mainly provided by the first cycle, the heavy - the second. The reserve of nuclear fuel in the star is limited and is constantly being spent on radiation. The process of fusion that emit energy and alter the composition of matter the star, combined with gravity, tending to compress the star, and also released energy, as well as radiation from the surface, taking allocated energy, are the main driving forces of stellar evolution.