Elemental Composition of the Universe

The first 3 minutes… http://www.jinaweb.org/movies/bangmovie.html

Nucleosynthesis Nucleo  “having to do with nuclei” Synthesis  “to make” It is the creation of new atomic nuclei! In astronomy, there are 2 types: Big Bang nucleosynthesis Stellar nucleosynthesis

BBN Some scientists say that as the early universe expanded & cooled, quarks “froze” into protons and neutrons. As it became too “cold” for other nuclear reactions to occur, unstable isotopes decayed Most matter was then Hydrogen (a single proton), He-4, deuterium, He-3, and Li-7

Stellar nucleosynthesis All other elements are the result of nuclear reactions in stars and supernova explosions. As stars evolve, they convert H and He into the heavier elements.