Nucleosynthesis:
The process of creating new atomic nuclei from pre-existingprotons and neutrons by a process of nuclear fusion. The primordial nucleons (hydrogen and helium) themselves were formed from the quark-gluon plasma in the first few minutes after the Big Bang, as it cooled to below ten million degrees, but nucleosynthesis of the heavier elements (including all carbon, oxygen, etc) occurs primarily in the nuclear fusionprocess within stars and supernovas.
Nucleus:
The tight cluster of nucleons (positively-charged protons and zero-charged neutrons, or just a singleproton in the case of hydrogen) at the centre of an atom, containing more than 99.9% of the atom’smass. The nucleus of a typical atom is about 100,000 smaller than the total size of the atom(depending on the individual atom).
Oscillating Universe:
A cosmological model, in which the universe undergoes a potentially endless series of oscillations, each beginning with a Big Bang and ending with a Big Crunch. After the Big Bang, the universeexpands for a while before the gravitational attraction of matter causes it to collapse back and undergo a “bounce”.
Panspermia:
The hypothesis that "seeds" of life exist already all over theuniverse, and that life on Earth may have originated through these "seeds", driven by a steady influx of cells or viruses arriving from space via comets. It is a more limited form of the related hypothesis of exogenesis, which also proposes that lifeon Earth was transferred from elsewhere in the universe, but makes no prediction about how widespread it may be.
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