Filamentary Molecular Clouds, Star Formation, and Pristine B-Fields, as seen by SOFIA/HAWC+, Gaia DR2, and Mimir Near-IR Polarimetry

Magnetic fields likely play roles in helping interstellar gas assemble into diffuse clouds and dark, molecular clouds and may play key roles in forming dense cores and the stars that form within them. But, most of the astrophysical laboratories probed for magnetic field properties are characterized by violent gas motions, ionizing radiation, stellar and disk outflows, and complex histories. Wouldn't it be nicer to peer into the earliest stages of isolated, low-mass, single star formation before all the loud music starts? We have done so, using the GF9-2 Class 0 YSO as our relatively clean laboratory, bringing to bear deep, near-infrared background starlight polarimetry with our Mimir instrument, Cycle 4 SOFIA/HAWC+ E-band polarimetry, and published optical and Planck polarization information. In addition, the newly released GAIA DR2 database has had a profound effect by distance-tagging virtually every star with measured NIR polarization. I will set the context for why GF9-2 is an important lab, how we have studied it, the nature of the very uniform B-field we find, and the high B-field strengths implied.