A survey searching for the epoch of assembling of Hubble types

Abstract

We have started a survey of galaxies at intermediate redshifts using the HST-STIS parallel fields. Our main goal is to analyse the morphology of faint galaxies in order to estimate the epoch of formation of the Hubble classification sequence. The high resolution of STIS images (0.05″) is ideal for this work and enables us to perform a morphological classification and to analyse the internal structures of galaxies. We find that 40% of the 290 galaxies are early types and that there are more irregulars and ellipticals at the fainter magnitudes.