Near-infrared Observations of the Proto-Planetary Nebula IRAS~07131-0147
  We have obtained near-infrared imaging and an optical spectrum of the proto-planetary nebula IRAS~07131-0147, a highly polarized bipolar reflection nebula believed to be in evolutionary transition from the asymptotic giant branch to the planetary nebula phase. Our images reveal point reflection symmetry in the lobes - a relatively rare morphological feature. We place an upper limit on the distance of 6.5 kpc. Utilizing numerical integrations of single grain scattering models we find the nebula to lie at an inclination angle of i=20\pm5 degrees in the plane of the sky. We present a refined geometric interpretation of IRAS~07131-0147 consistent with our new observational data and argue that the central star is likely to have an as yet undetected binary companion. 
D.R. Alves and D.W. Hoard