THE ASTRONOMICAL JOURNAL    VOLUME 109, NUMBER 2, PAGE 663        FEBRUARY 1995

        TERZAN 7: A YOUNG METAL-RICH GLOBULAR CLUSTER IN THE MILKY WAY

                    R. BUONANNO, C. E. CORSI, AND L. PULONE

 Osservatorio Astronomico di Roma, Via del Parco Mellini 84, 00136 Roma, Italy

                                 F. FUSI PECCI

                  Osservatorio Astronomico di Bologna, Italy
                    Electronic mail: flavio@astboz.astro.it

                        H. B. RICHER AND G. C. FAHLMAN

    Department of Geophysics and Astronomy, University of British Columbia
          Electronic mail: richer@astro.ubc.ca, fahlman@astro.ubc.ca


                                   ABSTRACT

    The first extensive CCD color-magnitude diagram for the metal-rich
    galactic globular cluster Terzan 7 is presented.  All age indicators
    derived from this diagram suggest that the cluster is young, about 70%
    of the age of 47 Tuc, which has similar metallicity.  A rich population
    of blue straggler stars is also found in this cluster.  With Terzan 7,
    the anomaly of young clusters is thus extended to cover almost the
    entire range of galactic globular cluster metallicities.  Several
    possibilities for the origin of young galactic globular clusters are
    discussed.