Spherical Cows in the Sky with Fab Four
  We explore spherically symmetric static solutions in a subclass of unitary
scalar-tensor theories of gravity, called the `Fab Four' models. The weak field
large distance solutions may be phenomenologically viable, but only if the
Gauss-Bonnet term is negligible. Only in this limit will the Vainshtein
mechanism work consistently. Further, classical constraints and unitarity
bounds constrain the models quite tightly. Nevertheless, in the limits where
the range of individual terms at large scales is respectively Kinetic Braiding,
Horndeski, and Gauss-Bonnet, the horizon scale effects may occur while the
theory satisfies Solar system constraints and, marginally, unitarity bounds. On
the other hand, to bring the cutoff down to below a millimeter constrains all
the couplings scales such that `Fab Fours' can't be heard outside of the Solar
system.
