Recent results suggest that the two planets in the HD 82943 system are
inclined to the sky plane by 20 +/- 4deg. Here, we show that the debris disk in
this system is inclined by 27 +/- 4deg, thus adding strength to the derived
planet inclinations and suggesting that the planets and debris disk are
consistent with being aligned at a level similar to the Solar System. Further,
the stellar equator is inferred to be inclined by 28 +/- 4deg, suggesting that
the entire star - planet - disk system is aligned, the first time such
alignment has been tested for radial velocity discovered planets on ~AU wide
orbits. We show that the planet-disk alignment is primordial, and not the
result of planetary secular perturbations to the disk inclination. In addition,
we note three other systems with planets at >10AU discovered by direct imaging
that already have good evidence of alignment, and suggest that empirical
evidence of system-wide star - planet - disk alignment is therefore emerging,
with the exception of systems that host hot Jupiters. While this alignment
needs to be tested in a larger number of systems, and is perhaps unsurprising,
it is a reminder that the system should be considered as a whole when
considering the orientation of planetary orbits.Comment: Accepted to MNRA
