  The short-period exoplanet HD 147506b (also known as HAT-P-2b) has an
eccentric orbit, raising the possibility that it migrated through planet-planet
scattering or Kozai oscillations accompanied by tidal dissipation. Either of
these scenarios could have significantly tilted the orbit relative to the host
star's equatorial plane. Here we present spectroscopy of a transit of HD
147506b, and assess the spin-orbit alignment via the Rossiter-McLaughlin
effect. We find the sky projections of the stellar spin axis and orbital axis
to be aligned within 14 deg. Thus we find no corroborating evidence for
scattering or Kozai migration, although these scenarios cannot be ruled out
with the present data.
