ESO
Hydrogen and helium — the two lightest elements — make up some 98 percent of the universe’s mass. It may seem surprising, then, to learn that scientists figured out where the heavier elements came from before they understood the big two.
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Hydrogen and helium — the two lightest elements — make up some 98 percent of the universe’s mass. It may seem surprising, then, to learn that scientists figured out where the heavier elements came from before they understood the big two.