EXTREME-ULTRAVIOLET FLUX FROM THE VIRGO CLUSTER - FURTHER EVIDENCE FOR A 500,000-KELVIN COMPONENT

A surprising discovery in x-ray astronomy was that clusters of galaxie s often contain vast quantities of hot (20 million kelvin) diffuse gas . Substantial diffuse extreme-ultraviolet (EUV) emission has recently been detected in the Virgo cluster of galaxies. Depending on the chara cter of the interstellar medium in our galaxy, this emission could be either an aspect of the hot cluster gas or a previously undetected 500 ,000-kelvin component. Analysis of the observational data in combinati on with our current knowledge of the interstellar medium revealed that the EUV flux cannot be an effect of the interstellar medium. Hence, a warm cluster component appears likely.