Why do we not find larger quantities of helium in the Sun's atmosphere? The Sun currently shines because H is being burned to He, and it has been doing this for about 4.57 Ga. But when we analyze the Sun's atmosphere, we do not find unusually large amounts of He. Why not?
Helium is burnt in Sun's core, and it is heavier (specific weight) than hydrogen.
Hence most of the helium stays in Sun's core.
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