The UV emission of elliptical galaxies
  Recent observational and theoretical developments concerning the origin of the ultraviolet emission from ellipticals are reviewed and discussed,with particular, reference to the extensive set of predictions contained in Greggio and Renzini (1990). Strong support to the preferred hot horizontal branch and AGB-manque' scenario for the origin of the UV emission has come from UIT, HUT and HST data. However, the UV sensitivity of such space telescopes has proved insufficient to unambiguously detect the predicted fading away of the UV rising branch with redshift, that we consider the ultimate check for this scenario. 
Laura Greggio and Alvio Renzini