  The dwarf spheroidal galaxy in Ursa Minor is apparently dark-matter
dominated, and is of very low surface brightness, with total luminosity only
equal to that of a globular cluster. Indeed its dominant stellar population is
old and metal-poor, very similar to that of a classical halo globular cluster
in the Milky Way Galaxy. However, the environment in which its stars formed was
clearly different from that in the globular clusters in the Milky Way Galaxy --
what was the stellar IMF in this external galaxy a long time ago? The fossil
record of long-lived, low-mass stars contains the luminosity function,
derivable from simple star counts. This is presented here. The mass function
requires a robust mass-luminosity relation, and we describe the initial results
to determine this, from our survey for eclipsing low-mass binaries in old open
clusters. The massive star IMF at early times is constrained by elemental
abundances in low-mass stars, and we discuss the available data. All data are
consistent with an invariant IMF, most probably of Salpeter slope at the
massive end, with a turnover at lower masses.
