The Morphology of Extremely Red Objects

Abstract

We briefly discuss our survey of Extremely Red Objects (EROs) with HST/NICMOS and deep ground-based images and summarize its results. We use the high-resolution NICMOS images to sub-divide EROs into morphological classes, tentatively arguing that about 60 % of EROs (18 out of 30) are early-type galaxies. About 20 % (6 out of 30 objects) appear to be flattened disk systems. Another 10 % (3 out of 30) have an irregular morphology. Thus, combining disk and irregular systems, our data are compatible with 30 % of EROs being dusty starbursts. A small fraction (3 out of 30) appear point-like even on the HST images and could therefore be either compact high redshift galaxies or stars in the Milky Way halo.