  We propose that magnetic reconnection at the heliopause only occurs where the
interstellar magnetic field points nearly anti-parallel to the heliospheric
field. By using large-scale magnetohydrodynamic (MHD) simulations of the
heliosphere to provide the initial conditions for kinetic simulations of
heliopause (HP) reconnection we show that the energetic pickup ions downstream
from the solar wind termination shock induce large diamagnetic drifts in the
reconnecting plasma and stabilize non-anti-parallel reconnection. With this
constraint the MHD simulations can show where HP reconnection most likely
occurs. We also suggest that reconnection triggers the 2-3 kHz radio bursts
that emanate from near the HP. Requiring the burst locations to coincide with
the loci of anti-parallel reconnection allows us to determine, for the first
time, the vector direction of the local interstellar magnetic field. We find it
to be oriented towards the southern solar magnetic pole.
