  The braneworld model of Dvali-Gabadadze-Porrati (DGP) is a theory where
gravity is modified at large distances by the arrested leakage of gravitons off
our four-dimensional universe. Cosmology in this model has been shown to
support both "conventional" and exotic explanations of the dark energy
responsible for today's cosmic acceleration. We present new results for the
gravitational field of a clustered matter source on the background of an
accelerating universe in DGP braneworld gravity, and articulate how these
results differ from those of general relativity. In particular, we show that
orbits nearby a mass source suffer a universal anomalous precession as large as
5 microarcseconds/year, dependent only on the graviton's effective linewidth
and the global geometry of the full, five-dimensional universe. Thus, this
theory offers a local gravity correction sensitive to factors that dictate
cosmological history.
