This picture shows the central portion of M15, photographed with Hubble's Wide Field Planetary Camera 2. The image is about 28 light-years across.

Credit: P. Guhathakurta (UCO/Lick Observatory, UC Santa Cruz), B. Yanny (Fermi National Accelerator Lab), D. Schneider (Pennsylvania State Univ.), J. Bahcall (Inst. for Advanced Study), and NASA/ESA