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The core is the high density, high temperature region at the center of the sun, where thermonuclear energy production takes place. It extends from the center to about 1/4 of a solar radius (1/64th of the sun's volume), but contains about half of the sun's mass. Practically all of the sun's energy production takes place in this region.
The sun uses hydrogen as fuel mostly through a series of nuclear reactions called the proton-proton chain, leaving behind helium ash. Just the bare facts .... In the proton-proton chain, 4 protons are converted to a helium nucleus, energy (carried by gamma rays) and some very light particles (neutrinos). The helium nucleus has 7-tenths of one percent less mass than the 4 protons and other stuff added together. The missing mass amounts to about 25 million electron volts (MeV) of energy. 100 trillion trillion trillion helium nuclei must be created every second to produce the 400 trillion trillion joules of energy we observe leaving the sun in a second. |
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