  We study light (u, d) quark matter with charm impurities. These impurities
are added to the Lagrangian density. We derive the equation of state (EOS) of
this kind of quark matter, which contains a Kondo phase. We explore this EOS
and study the structure of stars, identifying the effects of the Kondo phase.
Solving the TOV equations and computing the mass-radius diagram, we find that
the presence of a Kondo phase leads to smaller and lighter stars.
