abundance of the elements
Quick Summary
The abundance of elements refers to the relative number of atoms of different elements in the universe. Hydrogen and helium are by far the most common elements, with all others being much less abundant. This pattern generally shows a decline in abundance with increasing atomic mass, though there are exceptions and peaks, notably around iron.123
The origin of these elements is primarily attributed to nuclear fusion reactions within stars. The process begins with the fusion of hydrogen into helium, which releases significant energy. In more massive stars, helium can fuse into heavier elements up to iron. Elements heavier than iron require an input of energy to be produced and are formed through processes like supernovae explosions.123
Observations of stars, gas clouds, Earth, and meteorites provide the data for understanding these cosmic abundances. The chemical composition of stars changes over time due to these nuclear reactions, and some transmuted matter is released into interstellar space, influencing the composition of newly forming stars.124
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- isotopeElemental and isotopic abundances
The composition of any object can be given as a set of elemental and isotopic abundances. One may speak, for example, of the composition of the ocean, the solar system, or indeed the Galaxy in terms of its respective elemental and…
Read MoreThe composition of any object can be given as a set of elemental and isotopic abundances. One may speak, for example, of the composition of the ocean, the solar system, or indeed the Galaxy in terms of its respective elemental and…
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chemical elementGeochemical distribution of the elements…of the relative and absolute abundances of the chemical elements in the Earth and in its various parts—the crust, interior, atmosphere, and hydrosphere. This comprises a major part of the science of geochemistry, which is the study of the distribution of the chemical elements in space and time and the…
Read More…of the relative and absolute abundances of the chemical elements in the Earth and in its various parts—the crust, interior, atmosphere, and hydrosphere. This comprises a major part of the science of geochemistry, which is the study of the distribution of the chemical elements in space and time and the…
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- chemical elementCosmic abundances of the elements
The relative numbers of atoms of the various elements are usually described as the abundances of the elements. The chief sources of data from which information is gained about present-day abundances of the elements are observations of the chemical composition of…
Read MoreThe relative numbers of atoms of the various elements are usually described as the abundances of the elements. The chief sources of data from which information is gained about present-day abundances of the elements are observations of the chemical composition of…
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Milky Way GalaxyPrincipal population types…was made in determining the abundances of stars of the different population types by means of high-dispersion spectra obtained with large reflecting telescopes having a coudé focus arrangement. A curve of growth analysis demonstrated beyond a doubt that the two population types exhibited very different chemistries. In 1959 H. Lawrence…
Read More…was made in determining the abundances of stars of the different population types by means of high-dispersion spectra obtained with large reflecting telescopes having a coudé focus arrangement. A curve of growth analysis demonstrated beyond a doubt that the two population types exhibited very different chemistries. In 1959 H. Lawrence…
Read More- Milky Way GalaxyEmission nebulae
…that the ratio of the abundance of the heavier elements among the detected gases to hydrogen decreases outward from the centre of the Galaxy, a tendency that has been observed in other spiral galaxies.
Read More…that the ratio of the abundance of the heavier elements among the detected gases to hydrogen decreases outward from the centre of the Galaxy, a tendency that has been observed in other spiral galaxies.
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JupiterProportions of constituentsThe elemental abundances in Jupiter’s atmosphere can be compared with the composition of the Sun (see the right two columns of the table). If, like the Sun, the planet had formed by simple condensation from the primordial solar nebula that is thought to have given birth…
Read MoreThe elemental abundances in Jupiter’s atmosphere can be compared with the composition of the Sun (see the right two columns of the table). If, like the Sun, the planet had formed by simple condensation from the primordial solar nebula that is thought to have given birth…
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meteoriteCI carbonaceous chondritesWhen their elemental abundances are compared with those of the Sun, however, it turns out that the two are extremely similar. In fact, of all meteorite types, the CI chondrites most closely resemble the Sun in composition. Consequently, in devising a classification scheme, it makes sense to…
Read MoreWhen their elemental abundances are compared with those of the Sun, however, it turns out that the two are extremely similar. In fact, of all meteorite types, the CI chondrites most closely resemble the Sun in composition. Consequently, in devising a classification scheme, it makes sense to…
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starOrigin of the chemical elements…table lists the most abundant chemical elements; it represents an average pertaining to all cosmic objects in general.
Read More…table lists the most abundant chemical elements; it represents an average pertaining to all cosmic objects in general.
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