Color-magnitude diagrams (CMDs) reaching from the giant branches to Vlim ~ 27.0, or about three magnitudes fainter than the turnoff, have been obtained in V and I with WFPC2 on HST for NGC 2419, Pal 3, Pal 4 and Eridanus. These four clusters lie beyond the Magellanic Clouds in the far outer Galactic halo. NGC 2419, a massive cluster whose large core radius suggests that it has spent its life in the outer halo, has a CMD that is indistinguishable from that of M92. The other three, low luminosity objects exhibit the "second parameter" effect in which the red distribution of horizontal branch stars suggests a higher metallicity than that measured. Differential comparisons with the nearby clusters M3 and M5, which appear to bracket the metallicities of the outer halo clusters, are consistent with the distant objects being some ~ 1.5-2 Gyrs younger. This inferred age difference could be smaller (<1 Gyr) if either [Fe/H] or [alpha/Fe] is significantly lower than we have assumed. The properties of these clusters will be contrasted with developing knowledge of the Magellanic Cloud clusters.
New Views of the Magellanic Clouds
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