Ancient stars beyond the Local Group: RR Lyrae variables and Blue
  Horizontal Branch stars in Sculptor Group Dwarf Galaxies
  We have used Hubble Space Telescope ACS images to generate color-magnitude
diagrams that reach below the magnitude of the horizontal branch in the
Sculptor Group dwarf galaxies ESO294-010 and ESO410-005. In both diagrams blue
horizontal branch stars are unambiguously present, a signature of the existence
of an ancient stellar population whose age is comparable to that of the
Galactic halo globular clusters. The result is reinforced by the discovery of
numerous RR Lyrae variables in both galaxies. The occurrence of these stars in
the first direct confirmation of the existence of ancient stellar populations
beyond the Local Group and indicates that star formation can occur at the
earliest epochs even in low density environments.
