The Oldest Open Clusters

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Session 103 -- Open and Globular Clusters
Display presentation, Thursday, 12, 1995, 9:20am - 6:30pm

[103.02] The Oldest Open Clusters

R. L. Phelps (OCIW), K. A. Janes (Boston U.)

In a recent survey of candidate old open clusters, Phelps, Janes \& Montgomery (1994 AJ, 107, 1079) found 72 clusters with ages as great, or greater, than the Hyades (age about 0.8 Gyr) and 19 clusters with ages as great, or greater, than M67 (age about 5 Gyr). Among the oldest open clusters they found, and perhaps the oldest open cluster yet discovered, is Berkeley 17 (Be 17). Based upon a Morphological Age Index (MAI), Janes \& Phelps (1994 AJ, in press, November) determined that Be 17 may in fact be as old as the youngest globular clusters. If Be 17 is indeed that old, it becomes a useful probe of the transition from the halo to the disk.

In this paper we present our latest photometry of Be 17, which confirms the old age assigned by Phelps et al. (1994) and Janes $\&$ Phelps (1994), and also report on other recent photometric studies which add to the number of known old open clusters.

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