Note:
Fusion reactions in the sun occur under the pressure of immense gravity and mostly produce Helium through joining Hydrogen into heavier and heavier isotopes until becoming Helium-4. However, only 1 in 100x10^24 Hydrogen-1 collisions produce Deuterium nucleus which makes this pathway insufficient for Fusion Energy on Earth.
Reference Notes
- https://www.youtube.com/watch?v=dGr8VaITKbAyoutube.com