Newly determined high precision relative proper motions determined using images from the Hubble Space Telescope Wide-Field Planetary Camera were used along with radial velocity measurements to determine the dynamical distance to the globular cluster M15. The proper motion and radial velocity dispersions from a sample of 237 stars, located at an average radial distance of about 10 arcseconds from the cluster center yield a distance of 9.98 +- 0.47 kpc. This distance agrees to within the stated errors of other distance estimnates, but places this object about 5 percent closer than the currently adopted value of 10.4 kpc. Using this new distance, we estimate that RR Lyrae stars having [Fe/H] = -2.15 have a value of M_v(RR)= 0.51 $\pm$0.11. We also estimate that M15 has an age of about 13.2 Gyr, which places it among the oldest of the galactic globular clusters. From a comparison of the observed velocity dispersion with results from recent $N$-body calculations, we derive a mass of $M_C=4.5 \cdot 10^5 M_\odot$ for M15.


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