How do nuclear fusion reactions start?

1 Answer
May 10, 2016

Answer:

When the gravitational force of a proto-star's mass is sufficient to fuse hydrogen nuclei.

Explanation:

Fusion is the combining of atomic nuclei into larger atoms. The process releases huge amounts of energy. We achieve it currently only atomic bombs that use a fission nuclear reaction driver and at a very small and temporary scale with laser implosion of tritium.

In stars the driving force is the gravitational force of the stars mass. Thus, a star's nuclear fusion processes may be said to “start” when the accreting mass is sufficiently dense to force small nuclei together.