The legacy of SWAS: Water and molecular oxygen in the interstellar medium

Abstract

The Submillimeter Wave Astronomy Satellite has recently completed 5.5 years of successful operation. Among the legacies of the mission has been a greater understanding of the abundance and spatial distribution of H 2O and O 2 within molecular clouds. The model summarized here provides an explanation for the relatively low gaseous H 2O abundance and the high H 2O–ice abundance in cold dense clouds, the higher H 2O abundance toward diffuse clouds, the low O 2 abundance toward all clouds observed.