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\begin{document}

\title{THE STRUCTURE OF THE SUPER STAR CLUSTERS IN NGC\,1569\\
~\\
FROM \protect{\boldmath{$H\!ST$\/}} WFPC2 IMAGES\/\thanks{Based on observations 
with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope 
Science Institute, which is operated by AURA for NASA under contract 
NAS5-26555}}

\author{Guido De Marchi,\thanks{Current address: European Southern Observatory, 
Karl-Schwarzschild-Str. 2, D-85748 Garching, Germany, e-mail: demarchi@eso.org}
Mark Clampin\\
\\
Space Telescope Science Institute, 3700 San Martin Drive, Baltimore, MD 21218\\
e-mail: clampin@stsci.edu\\
\\
\and
Laura Greggio\\
\\
Universit\`a di Bologna, Dipartmento di Astronomia, 
Via Zamboni 33\\
I-40126 Bologna, Italy\\
e-mail: greggio@astbo3.bo.astro.it\\
\\
\and
Claus Leitherer, Antonella Nota\\
\\
Space Telescope Science Institute\\
leitherer@stsci.edu, nota@stsci.edu\\
\\
\and
Monica Tosi\\
\\
Osservatorio Astronomico di Bologna, Via Zamboni 33,
I-40126 Bologna, Italy\\
e-mail: tosi@astbo3.bo.astro.it}

\tobe{10 April 1997}{Astrophysical Journal (Letters), 479}
\recacc{27 November 1996}{17 January 1997}
\maketitle

\abstract{
We present high-resolution observations of the super star clusters in
the nearby irregular galaxy NGC\,1569 obtained with the WFPC2 on board
the HST. Our analysis shows that the brightest of these clusters,
NGC\,1569--A, results from the superposition of two clusters with an
angular separation of $\sim 0\secpoint2$. Recent ground-based
spectroscopy revealed that both red supergiant and Wolf-Rayet stars are
associated with NGC\,1569--A. According to current evolutionary models,
this finding requires the coexistence of two non coeval stellar
populations within the same cluster. Our discovery that NGC\,1569--A is
double simplifies the interpretation, as red supergiants and Wolf-Rayet
stars may belong to different clusters. We derive for the three
clusters half-light radii of $\sim 1.6$--1.8\,pc, smaller than
indicated by previous HST observations. The size, mass, and luminosity
of the brightest of these super clusters confirm that these objects
could be young globulars, reinforcing previous conclusions.}