Summary

We have reviewed the observed properties of these new compact objects discovered in the Fornax Cluster. Their luminosities are intermediate between those of known globular clusters and compact dwarf galaxies, but they are consistent with the bright end of the luminosity function of the the nuclei of nucleated dwarf ellipticals. The 2dF spectra are suggestive of old (metal-rich) stellar populations, more like globular clusters than dwarf galaxies. Finally the radial distribution of the compact objects is more centrally concentrated than cluster galaxies in general, but extends further than the known globular cluster system of NGC 1399.

These objects are most likely either massive star clusters (extreme globular clusters or tidally-stripped dwarf galaxy nuclei) or very compact, low-luminosity dwarf galaxies. In the latter case these new compact objects would be very low-luminosity counterparts to the peculiar compact galaxy M32. This would be particularly interesting given the lack of M32-like galaxies at brighter luminosities (Drinkwater & Gregg 1998). With higher resolution images and spectra we will be able to measure the mass-to-light ratios of these objects and determine which of these alternatives is correct.

© Copyright Astronomical Society of Australia 1997