This substance's spectrum displays the D3 Fraunhofer line. When this substance accretes to the surface of a white dwarf or ce
This substance's spectrum displays the D3 Fraunhofer line. When this substance accretes to the surface of a white dwarf or ceases to be degenerate in contracting stars, its namesake flash occurs. Hans Bethe discovered its production by the CNO cycle, and three units of it combine in a namesake exergonic process that occurs mainly in red giants. This first element to be detected extraterrestrially is the heaviest and last product of the proton-proton chain, the fusion reaction in most stars. For 10 points, identify this second-most abundant element in the universe, named for its abundance in our sun.
This substance's spectrum displays the D3 Fraunhofer line. When this substance accretes to the surface of a white dwarf or ceases to be degenerate in contracting stars, its namesake flash occurs.
helium [nucleus or atom; prompt on "He"; accept alpha particles until "element" is read]