Mapping the Interstellar Magnetic Field Around the Heliosphere with
  Polarized Starlight
  Starlight that becomes linearly polarized by magnetically aligned dust grains
provides a viable diagnostic of the interstellar magnetic field (ISMF). A
survey is underway to map the local ISMF using data collected at eight
observatories in both hemispheres. Two approaches are used to obtain the
magnetic structure: statistically evaluating magnetic field directions traced
by multiple polarization position angles, and least-squares fits that provide
the dipole component of the magnetic field. We find that the magnetic field in
the circumheliospheric interstellar medium (CHM), which drives winds of
interstellar gas and dust through the heliosphere, drapes over the heliopause
and influences polarization measurements. We discover a polarization band that
can be described with a great circle that traverses the heliosphere nose and
ecliptic poles. A gap in the band appears in a region coinciding both with the
highest heliosheath pressure, found by IBEX, and the center of the Loop I
superbubble. The least-squares analysis finds a magnetic dipole component of
the polarization band with the axis oriented toward the ecliptic poles. The
filament of dust around the heliosphere and the warm helium breeze flowing
through the heliosphere trace the same magnetic field directions. Regions along
the polarization band near the heliosphere nose have magnetic field
orientations within 15 degrees of sightlines. Regions in the IBEX ribbon have
field directions within 40 degrees of the plane of the sky. Several spatially
coherent magnetic filaments are within 15 pc. Most of the low frequency radio
emissions detected by the two Voyager spacecraft follow the polarization band.
The geometry of the polarization band is compared to the Local Interstellar
Cloud, the Cetus Ripple, the BICEP2 low opacity region, Ice Cube IC59 galactic
cosmic ray data, and Cassini results.
