Hubble Space Telescope and Ground-Based Optical Imaging of the Proto-Planetary Nebula M1-92

Abstract

We present HST and ground-based images of the bipolar proto-planetary nebula M1-92. Trammell et al. (1993) studied M1-92 using spectropolarimetry and concluded that the continuum emission is reflected from the inner regions of the object, the forbidden lines are formed locally in the bipolar lobes, and the permitted lines are partially reflected and partially formed in the bipolar lobes. The emission produced in the lobes of M1-92 is indicative of shock heating, V s = 60 – 100 km s-1. Shock emission dominates the optical line spectra of the lobes of M1-92 and is a powerful probe into the properties of the mass loss occurring between the AGB and PN phases of evolution.