| Before nucleosynthesis begins, protons and neutrons are continually interconverting by means of weak nuclear interactions. |
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| The one problem with the story of stellar nucleosynthesis as developed in the 1950s was that it could not explain where helium came from. |
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| They more or less figured out the whole story, including predictions for primordial nucleosynthesis and the cosmic microwave background. |
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| Evidence from both the cosmic microwave background and primordial nucleosynthesis gives tight bounds on how much ordinary matter there is. |
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| The starting point in tracing planetary evolution is nucleosynthesis, the formation of the chemical elements on a cosmic scale. |
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| Fusion reactions are the primary energy source of stars and the mechanism for the nucleosynthesis of the light elements. |
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| A star is born when it starts igniting hydrogen then transforms this hydrogen into helium, in a process called nucleosynthesis. |
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| Physicists call this process nucleosynthesis, and it had to occur before the structures we observed today, such as atoms and molecules, could exist. |
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| One possible modification concerns models of so-called inhomogeneous nucleosynthesis. |
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| Thereafter, nucleosynthesis produced the elemental abundance of the early Universe. |
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| Heavy element transmutation was observed bull-dozed by the bow shock that matched stellar and supernova nucleosynthesis. |
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| The evolution of stars can be viewed as a passage through various stages as thermonuclear reactions and nucleosynthesis cause compositional changes over long time spans. |
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| In a 1953 paper, Alpher, Herman, and American physicist James Follin provided a stage-by-stage history of the early universe, concluding that nucleosynthesis was essentially complete after 30 minutes of cosmic expansion. |
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| This amount is lower than the expected value, suggesting that nucleosynthesis ceased in the solar system material about 2 × 108 years before the meteorites and planets solidified. |
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| Even better, the temperatures reached can still be increased, which then might allows at a longer term nucleosynthesis or incineration of radioactive elements. |
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| The universe is a trillion times larger than it was at nucleosynthesis. |
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| This evidence bolstered the hypothesis that heavier elements are the product of nucleosynthesis in stars. |
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| Much of the past work on isotopic composition of iron has focused on the nucleosynthesis of 60Fe through studies of meteorites and ore formation. |
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| The most abundant iron isotope 56Fe is of particular interest to nuclear scientists because it represents the most common endpoint of nucleosynthesis. |
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| Neutron-capture nucleosynthesis can occur during the second giant phase of low-mass stars, near the core where the helium is partially converted to carbon. |
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