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There are two types of planetary noble gases: One, containing isotopically “anomalous” argon, krypton and xenon but isotopically “normal” helium and neon, was derived from outer stellar regions. The other, consisting almost entirely of isotopically “normal” argon, krypton and xenon, with little or no helium or neon, was derived from inner stellar regions. Mixing of nucleosynthesis products from different regions of a supernova is responsible for the observed correlations between elemental and isotopic ratios of planetary noble gases in different classes of meteorites. The solar system condensed directly from the chemically and isotopically heterogeneous debris of a single supernova. There is no convincing evidence, however, of separate nucleogenetic components in neon. Fractionation and spallation can account for all previously identified components of trapped meteoritic neon, Ne‐A, Ne‐B, Ne‐C, Ne‐D, Ne‐E, Ne‐Al, Ne‐A2, Ne‐E(L), Ne‐E(H) and Ne‐O, and this same mechanism also explains differences between the isotopic compositions of meteoritic, atmospheric, and solar wind neon. Variations in the abundance pattern of planetary noble gases are primarily the result of stellar fusion reactions and physical adsorption, rather than gas solubility.

The abundance pattern of noble gases in Thailand tektites shows an anomalous spike of neon, apparently from the diffusion of atmospheric neon through the glass. The isotopic compositions of non‐radiogenic Ne, Ar, Kr, and Xe are atmospheric, but the Ar/Xe and Kr/Xe ratios in the tektites are each about an order of magnitude lower than the values in air.

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