Chemical matter is the part of the universe which is made of chemical atoms. This part of the universe does not include dark energy, dark matter, black holes or various forms of degenerate matter, such as compose white dwarf stars and neutron stars. Recent data from what Wilkinson Microwave Anisotopy Probe (WMAP), suggests that only about 4% of the total mass of the part of the universe which is within range of the best theoretical telescopes (i.e., which may be visible, because light has reached us from it), is made of chemical matter. About 22% is dark matter, and about 74% is dark energy. Wikipedia does not have an article with this exact name. ... The periodic table of the chemical elements A chemical element, or element for short, is a type of atom that is defined by its atomic number; that is, by the number of protons in its nucleus. ... Properties For alternative meanings see atom (disambiguation). ... In physical cosmology, dark energy is a hypothetical form of energy that permeates all of space and tends to increase the rate of expansion of the universe. ... In astrophysics and cosmology, dark matter refers to hypothetical matter of unknown composition that does not emit or reflect enough electromagnetic radiation to be observed directly, but whose presence can be inferred from gravitational effects on visible matter. ... This article is about the astronomical body. ... This article or section does not adequately cite its references or sources. ... This article is about the celestial body. ...

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