Tentative Identification of Interstellar Dust in the Nose of the Heliosphere

Abstract

Observations of the weak polarization of light from nearby stars, reported by Tinbergen (1982), are consistent with polarization by small, radius <0.14 microm, interstellar dust grains entrained in the magnetic wall of the heliosphere. The direction of maximum polarization is offset by ~35 deg from the heliosphere nose, and extends to low ecliptic latitudes. An offset is found between the direction of the best aligned dust grains, and the upwind direction of the undeflected large interstellar grains seen by Ulysses and Galileo. In the aligned-grain region, the strength of polarization anti-correlates with ecliptic latitude, indicating that the magnetic wall is predominantly at negative ecliptic latitudes, which is consistent with predictions of Linde (1998). These data are consistent with an interstellar magnetic field tilt of 60 deg with respect to the ecliptic plane, and parallel to the galactic plane. Interstellar dust grains captured in the heliosheath may also introduce a weak, but important, large scale contaminant for the cosmic microwave background signal with a symmetry consistent with the relative tilts of \Bis and the ecliptic.

Submitted to Astrophysical Journal Letters

Cited by in corpus (12)

• CMB Anomalies after Planck
• The Uncorrelated Universe: Statistical Anisotropy and the Vanishing Angular Correlation Function in WMAP Years 1-3
• Large-angle anomalies in the CMB
• Large-scale alignments from WMAP and Planck
• The linear polarization of nearby bright stars measured at the parts per million level
• Mysteries on Universe's Largest Observable Scales
• Contamination cannot explain the lack of large-scale power in the cosmic microwave background radiation
• The Local Bubble and Interstellar Material Near the Sun
• The S1 Shell and Interstellar Magnetic Field and Gas near the Heliosphere
• The local dust foregrounds in the microwave sky: I. Thermal emission spectra
• Large Scale Traces of Solar System Cold Dust on CMB Anisotropies
• Cosmological Implications of the CMB Large-scale Structure