posted on Mar, 1 2017 @ 11:20 PM
a reply to: Golantrevize
All it takes is an large amount of hydrogen (and when I say large, I mean astronomical amounts).
A few atoms of it clump together.....this attracts more,,,,,then more......and even more, and it keeps going until at some point it reaches critical
mass and you end up with a fusion reaction.
What helps is when you have some event near by that can push it along a bit: a super nova exploding, the pressure waves help push the hydrogen
A star passing by: it's gravity pulling on they hydrogen, causing it to clump together.
It's a process that takes a lot of time though, hundreds of thousands to millions of years.
Size of the star will depend upon how much of that hydrogen is available, and how dense that amount is. Super giant stars tend to form because there
was a lot of hydrogen available that was dense enough to be collected fast enough by the star forming.
Small stars, like red dwarfs formed because there was not as much stellar hydrogen for them to form from, but there was enough to start fusion up
It's a pretty interesting field and there are tons of books and docus on the subject.