P36	February 1999

¹ European Southern Observatory, Alonso de Cordova 3107, Casilla 19001, Santiago, Chile
² Observatoire de Marseille and Institut Cassendi, 2 place Le Verrier, F-13004 Marseille, France
³ Institut d'Astrophysique de Paris, 98bis Bld Arago, F-75014 Paris, France
⁴ Institut d'Astrophysique et de Géophysique - Université de Liège, Avenue de Cointe 5, 4000 Liège, Belgium
⁵ DAEC-URA 173, Observatoire de Paris, F-92195 Meudon Principal cedex, France

⁺ Based on observations carried out at NTT in La Silla, operated by the European Southern Observatory, during Director's Discretionary Time.

Abstract

     High resolution, ground based R and I band observations of the ultra compact dwarf galaxy POX 186 are presented. The data, obtained with the ESO New Technology Telescope (NTT), are analyzed using a new deconvolution algorithm which allows one to resolve the innermost regions of this stellar-like object into three Super-Star Clusters (SSC). Upper limits to both masses (M ~ 10⁵ M) and the physical sizes ( 60pc) of the SSCs are set. In addition, and maybe most importantly, extended light emission underlying the compact star-forming region is clearly detected in both bands. The R-I color rules out nebular H contamination and is consistent with an old stellar population. This casts doubt on the hypothesis that Blue Compact Dwarf Galaxies (BCDG) are young galaxies.