Synthesis of Light Elements
•4He always has an abundance of about 23-25%, and there are traces of D, 3He, and 7Li.  No heavier elements because no stable isotopes with mass numbers 5 and 8.  [Need stars, and triple-α process.]
•4He is always observed to be > 23%.
•D, other light trace elements, are destroyed in stars, not created. •These results are remarkable and important!
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