STAR FORMATION

The birth and death of various stars occurs every second in the universe. In our previous blog we saw about “Nebula -the nursery of stars”. Stars are the building blocks of the galaxies. So now let’s see how stars comes into existence from the nebulae.

• The nebula is made of 99% hydrogen.
• After nebula formation the interstellar materials starts to cool.
• Due to this, atom, ions and particles comes together (formation of clumps) and compression occurs.
• Owing to this the nebulae contracts and splits into separate clumps of different masses.
• Each clump will try to evolve as an individual star.
• Since the density of clumps is high the temperature will eventually increase.
• Because of it’s high mass gravitational force starts to play it’s role.
• This clump will undergo further contraction.
• Eventually the temperature and density of the clumps will increase and thus they are recognized as a protostar having a developed photosphere.
• In case if the mass of the clumps is too small, then it will fail to become a star. These clumps are further called as ‘brown dwarfs’, one of it’s typical example is ‘the Jupiter planet’.
• If the clumps successfully forms the protostar, the gravitational force further compress it.
• When the core temperature reaches 10⁷ K, the fusion reaction starts giving the outward pressure balancing the inward gravitational pull.
• Thus a stable star is born.

                                                                   

                                             https://www.astronomynotes.com/starsun/s7.htm