![]() Cameron (1957a,b, whose lack of catchy abbreviations can be blamed on the more extensive of his two presentations having remained classified for some years). Fowler, and Fred Hoyle (1957 frequently B2FH) and Alastair G.W. Nucleosynthesis, as we now understand it, sprang nearly fully grown in 1957 from the five more or less Jovian foreheads of E. Key words: Nucleosynthesis - Nuclear reactions - Stars: abundances - Interstellar Medium: abundances - Cosmology - Galaxies: evolution of The discussion presupposes a reader (a) with some prior knowledge of astronomy at the level of recognizing what is meant by an A star and an AGB star and (b) with at least a mild interest in how we got to where we currently are. ![]() Significant advances in the intervening years include (a) observations of elemental and a few isotopic ratios in many more extra-solar-system sites, including metal-poor dwarf irregular galaxies, where very little has happened, and supernovae and their remnants, where a great deal has happened, (b) recognition of the early universe as good for making all the elements up to helium, (c) resolution of heavy element burning in stars into separate carbon, neon, oxygen, and silicon burning, with fine tuning of the resulting abundances by explosive nucleosynthesis in outgoing supernova shock waves, (d) clarification of the role of Type I supernovae, (e) concordance between elements produced in short-lived and long-lived stars with those that increased quickly and slowly over the history of the galaxy, and (f) calibration of calculations of the evolution and explosion of massive stars against the detailed observations of SN 1987A. ![]() The basic scheme of nucleosynthesis (building of heavy elements from light ones) has held up very well since it was first proposed more than 30 years ago by E.M. The origin and abundances of the chemical elements revisitedĪstronomy Program, University of Maryland, College Park, MD 20742, USA Department of Physics, University of California, Irvine, CA 92717, USA ![]()
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