HST observations of the very young SMC ``blob'' N 88A

High-resolution Hubble Space Telescope images have allowed us for the first time to resolve the compact SMC ionized ``blob'' N 88A (diameter ~ ,3''.5 or 1 pc). This very young H ii,region, which is hatching from its natal molecular cloud, is heavily affected by absorbing dust associated with the cloud. The interstellar reddening towards N 88A is on average A_V ~ ,1.5 mag and strikingly rises to more than 3.5 mag in a narrow dust band crossing the core of the H ii,region. Such a high extinction is unprecedented for an H ii,region in the metal-poor SMC. We present the photometry of some 60 stars lying towards the OB association at the center of which lies N 88A. The exciting star(s) of N 88A is not detected, due to the heavy extinction. The chronology of star formation is discussed for the whole region. Based on observations with the NASA/ESA Hubble Space Telescope obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under NASA contract NAS 5-26555. Based on observations obtained at the European Southern Observatory, La Silla, Chile. Table 1 is only available in electronic form at the CDS via anonymous ftp to cdsarc.u-strasbg.fr(130.79.128.5) or via http://cdsweb.u-strasbg.fr/Abstract.html