Abstract
Revolutionary changes in our awareness of the physical state of gases in interstellar space have been precipitated by new theoretical realizations and observational evidence. Mechanical energy released by supernovae and early-type stars is now thought to be an important source of heating and agitation for the interstellar medium (McCray and Snow 1979). The propagation and dissipation of this energy gives rise to a broadly distributed network of gas at low densities and high temperatures, revealed to us by its emission of soft x-rays (Cox 1977, Tanaka and Bleeker 1977) and the pervasiveness of highly ionized atoms (with 0 VI being the most conspicuous tracer, see York 1974, Jenkins and Meloy 1974, review by Jenkins 1977).
Publisher
Cambridge University Press (CUP)