Post by glactus on Sept 23, 2011 1:12:19 GMT
The birth of a star stage one - A Protostar
It takes billions of years for molecules of Hydrogen, floating around in space, to come together in sufficient mass to eventually coalesce into a protostar (the first stage), it usually takes another event, such as the shockwave from a supernova to give it the "nudge it requires", allowing gravity to come into play, for this to happen.
The birth of a star stage two - A T Tauri star
But that's only the beginning. Another 100,000 years or so later, when the protostar has gathered all the gas that it can, it becomes a very hot ball of gas called a T Tauri star. It still doesn't have enough mass, and hence pressure, to begin internal nuclear fusion, even though it can appear as bright as a regular star.
The birth of a star final -Our star the Sun
It's going to take gravity around another 100 million years to collapse the T Tauri to the point where it's core can begin nuclear fusion. This is the point at which you can say that the star is 'born'.
Credits: These are non copywrite images
Text by Wikipedia