When two hydrogen atoms fuse to become one helium atom.
Hydrogen fusion does not occur in the corona of the sun. Fusion reactions occur in the sun's core where conditions are hot and dense enough for hydrogen nuclei to combine to form helium, releasing energy in the process. The corona is cooler and less dense than the core, so fusion cannot take place there.
When hydrogen stocks run out
The fusion of Hydrogen into Helium.
Not enough pressure or temperature.
In the cores of stars and hydrogen bombs.
High temperature, high pressure, and the presence of hydrogen isotopes like deuterium and tritium are necessary conditions for the continuous fusion of hydrogen to occur in a controlled manner.
The fusion of Hydrogen into Helium causes heat and radiation to occur.
hydrogen fusion
If there is no hydrogen left at the core of star then hydrogen fusion cannot occur. What happens in the core of a star before that happens is that helium begins to fuse, and then the other elements going up the periodic table until carbon. And then if the star explodes into a supernova, traces of the higher elements are fused as well.
In stars. As far as I know this is the only place.
In the core of the Sun, hydrogen atoms fuse to form helium in a process known as hydrogen fusion. This is the primary fusion process occurring in the Sun. As the core hydrogen is depleted, helium fusion into heavier elements like carbon and oxygen will occur in later stages of the Sun's evolution.
a hydrogen bomb is a fusion bomb. even though in standard types of hydrogen bombs 90% of the yield is fission, caused by uranium-238 fission by 15 MeV neutrons from the fusion reaction.