  The pulsar B1620-26 has two companions, one of stellar mass and one of
planetary mass. We detected the stellar companion using Hubble Space Telescope
observations. The color and magnitude of the stellar companion indicate that it
is an undermassive white dwarf ($0.34 \pm 0.04 M_{\odot}$) of age $480\pm 140$
Myr. This places a constraint on the recent history of this triple system and
supports a scenario in which the current configuration arose through a
dynamical exchange interaction in the cluster core. This implies that planets
may be relatively common in low-metallicity globular clusters and that planet
formation is more widespread and happened earlier than previously believed.
