Nucleosynthesis hydrogen helium
Much more precise determinations of helium abundance can be made by spectroscopy of gaseous nebulae, since the optical lines of hydrogen and helium are both mainly excited by recombination and are (except in a few identifiable cases) optically thin. Which shows the correct order of events during the process of nucleosynthesis 1hydrogen nucleus formed,isotope of hydrogen tritum formed,helium nucleus formed. The higher the density, the more helium produced during the nucleosynthesis era the current measurements indicate that 75% of the mass of the universe is in the form of hydrogen, 24% in the form of helium and the remaining 1% in the rest of the periodic table (note that your body is made mostly of these `trace' elements).
Processes there are a number of astrophysical processes which are believed to be responsible for nucleosynthesis the majority of these occur in within stars, and the chain of those nuclear fusion processes are known as hydrogen burning (via the proton-proton chain or the cno cycle), helium burning, carbon burning, neon burning, oxygen burning and silicon burning. The atoms in your body – apart from the hydrogen – were all made in stars by stellar nucleosynthesis stars on the main sequence get the energy they shine by from nuclear reactions in . Stellar nucleosynthesis is the collective term for the nucleosynthesis, or nuclear reactions, taking place in stars to build the nuclei of the elements heavier than hydrogen fusion reactions of light elements power the stars and produce virtually all elements in a process called nucleosynthesis.
Apart from hydrogen and helium which are the products of big bang nucleosythesis all observed chemical elements heavier that helium (c, o, called metals by astronomers) are synthesised inside stars stellar nucleosynthesis provides clues not only to stellar evolution but also to space-time . This is the dominant work in stellar nucleosynthesis it provided the roadmap to how the most abundant elements on earth had been synthesized from initial hydrogen and helium, making clear how those abundant elements increased their galactic abundances as the galaxy aged. Stellar nucleosynthesis is the process by which elements are created within stars by combining the protons and neutrons together from the nuclei of lighter elements all of the atoms in the universe began as hydrogen fusion inside stars transforms hydrogen into helium, heat, and radiation heavier . Nucleosynthesis or nucleogenesis, in astronomy, production of all the chemical elements  from the simplest element, hydrogen, by thermonuclear reactions within stars, supernovas, and in the big bang at the beginning of the universe (see nucleus  nuclear energy ).
Hydrogen and helium and some lithium, boron, and beryllium were created when the universe was created all of the rest of the elements of the universe were produced by the stars in nuclear fusion reactions. Big bang nucleosynthesis the predicted abundance of elements heavier than hydrogen, the fact that helium is nowhere seen to have an abundance below 23% mass . Big bang nucleosynthesis gamow, alpher and herman proposed the hot big bang as a means to produce all of the elements however, the lack of stable nuclei with atomic weights of 5 or 8 limited the big bang to producing hydrogen and helium. But here on earth, hydrogen and helium are only a small part of the world we inhabit by mass, hydrogen and helium combined make up far less than 1% of the earth, and even if we restrict ourselves . It was then that hydrogen and helium formed to become the content of the first stars, and this primeval process is responsible for the present hydrogen/helium ratio of the cosmos with the formation of stars, heavier nuclei were created from hydrogen and helium by stellar nucleosynthesis, a process that cont .
Nucleosynthesis hydrogen helium
Hydrogen and helium and trace amounts of deuterium and lithium why is the era of nucleosynthesis so important in determining the chemical composition of the universe except for the small amount of matter produced later by stars, the chemical composition of the universe is the same now as at the end of the era of nucleosynthesis. The segment is discussing nucleosynthesis or the origin of elements in our solar system so you go from hydrogen and helium in the lower left-hand corner of the . The most prevalent reaction in smaller stars like our sun is the fusion of hydrogen into helium by the proton-proton chain in more massive stars this fusion occurs via the carbon cycle ‘nucleo-‘ means ‘to do with nuclei’ ‘synthesis’ means ‘to make’, so nucleosynthesis is the creation of (new) atomic nuclei. Our sun is currently burning, or fusing, hydrogen to helium this is the process that occurs during most of a star's lifetime after the hydrogen in the star's core is exhausted, the star can burn helium to form progressively heavier elements, carbon and oxygen and so on, until iron and nickel are formed.
- Stellar nucleosynthesis is the theory explaining the creation (nucleosynthesis) of chemical elements by nuclear fusion reactions between atoms within the stars stellar nucleosynthesis has occurred continuously since the original creation of hydrogen, helium and lithium during the big bang.
- According to the big bang theory, the early universe was hot enough to allow the nucleosynthesis of hydrogen, helium, and small amounts of lithium and beryllium deuterium, a common isotope of hydrogen, was also important as a reactant in many of the reactions required to form helium.
Nucleosynthesis is the process of creating new atomic nuclei from pre-existing nucleons hydrogen and helium were clearly far more abundant than any of the other . After the bulk of a star's hydrogen has been converted to helium by either the proton-proton or carbon-nitrogen-oxygen process, the stellar core contracts (while the outer layers expand) until sufficiently high temperatures are reached to initiate helium-burning by the triple-alpha process in this process, three helium nuclei (alpha . Of times rarer than hydrogen and helium, the most abundant elements in general, as we move up the fusion chain, higher and higher temperatures and pressures and densities are required to generate heavier and heavier elements. Apart from nuclear fusion in stars, there is also what is called as nucleosynthesis this is defined as the production or creation of new elements through the process of nuclear reactions in this process, as more and more particles fuse together, such as the atoms of hydrogen and helium in stars, the new product of .