I have always heard that everything we see is "star stuff" from previous stars that died after converting their hydrogen into heavier elements. So how is there any hydrogen left for the Sun and planets?
William Manthey, Beacon Falls, Connecticut
Published: Monday, March 25, 2013
Hydrogen is the main source of fuel for stars like the Sun. However, the atoms near the center of a star are the only ones that participate in the fusion reactions that power it. These atoms make up only a small fraction of all those in a star.
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