Stellar Atmospheres: The Sources of Interstellar Molecules

Abstract

The analysis of the abundance of interstellar molecules in compact H II regions suggests that the molecules are formed in stellar atmospheres (possibly of protostars or of late type stars), transported to the location of the neutral clouds in the cpmpact H II regions, and shielded from decomposition due to stellar radiation by the dust in the clouds. Cometary nuclei and interstellar dust are argued from the astrochemical point of view to be dirty ice of the second kind (or a sort of frozen interstellar molecules). The chemical structure of the primordial solar nebula is discussed under the assumption that long-period comets consist of the most primordial substances of the solar system.