The young open cluster Berkeley 55
  We present UBV photometry of the highly reddened and poorly studied open
cluster Berkeley 55, revealing an important population of B-type stars and
several evolved stars of high luminosity. Intermediate resolution far-red
spectra of several candidate members confirm the presence of one F-type
supergiant and six late supergiants or bright giants. The brightest blue stars
are mid-B giants. Spectroscopic and photometric analyses indicate an age 50+-10
Myr. The cluster is located at a distance d~4kpc, consistent with other tracers
of the Perseus Arm in this direction. Berkeley 55 is thus a moderately young
open cluster with a sizable population of candidate red (super)giant members,
which can provide valuable information about the evolution of intermediate-mass
stars.
