HM Sagittae : the evolution of a symbiotic nova.

Abstract

HM Sge was discovered in 1975, when it became a symbiotic nova. HM Sge is still evolving. Since its discovery, significant spectral changes have taken place in the ultraviolet, the radio, as well as in the visual wavelength ranges. Here, IUE observations from 1982 to 1989 are reported. The implications of the available spectral information since the outburst in 1975 are then discussed.