  If a light gluino exists, the lightest gluino-containing baryon, the \OSO, is
a possible candidate for self-interacting dark matter. In this scenario, the
simplest explanation for the observed ratio $\Omega_{dm}/\Omega_b \approx 6-10$
is that $m_{S^0} \sim 900$\MeVcs; this is not at present excluded by particle
physics. Such an \OSO could be present in neutron stars, with hyperon formation
serving as an intermediate stage. We calculate equilibrium compositions and
equation of state for high density matter with the \OSO, and find that for a
wide range of parameters the properties of neutron stars with the \OSO are
consistent with observations. In particular, the maximum mass of a nonrotating
star is $1.7-1.8 M_\odot$, and the presence of the \OSO is helpful in
reconciling observed cooling rates with hyperon formation.
