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Neon (Ne) is the element with atomic number 10, symbol Ne. Its most common isotope has mass number 20, but 21 and 22 are also stable. It is the fifth most common element in the universe but rare on Earth. It is a noble gas (aka inert gas), one of six elements with such an atomic number that an atom of the element is very unlikely to bind with another atom, i.e., it tends not to occur in compounds, and tends to be an atomic gas except at very low temperatures.
Its nuclei are synthesized by carbon burning and the alpha process, in stars and supernova. In sufficiently massive stars, a neon-burning shell forms during the asymptotic giant branch (AGB) phase.