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[3.08] HST Observations of the Globular Clusters of NGC 6822

D. B. Zucker, P. W. Hodge (University of Washington)

The globular clusters of spiral and elliptical galaxies are reasonably well-studied, and they have yielded a great deal of information about the early histories of these types of galaxies. However, comparatively little is known about the globular clusters of irregular galaxies. As part of a study of the Local Group irregular galaxy NGC 6822, we used HST to observe the four potential globular clusters identified by Hubble in 1925.

We obtained WFPC-2 images of all four targets in the F555W (~V) and F814W (~I) filters, and generated color-magnitude diagrams from the resulting photometry. The data reveal that three targets are globular or globular-like clusters representing a wide range of ages: very old (Hubble VII), intermediate in age (Hubble VIII), and young (Hubble VI). The fourth target, Hubble IV, is an H II region.