D ec 1 99 5 A Butterfly in the Making : Revealing the Near - Infrared Structure of Hubble 12

We present deep narrowband near-IR images and moderate resolution spectra of the young planetary nebula Hubble 12. These data are the first to show clearly the complex structure for this important planetary nebula. Images were obtained at λ = 2.12, 2.16, and 2.26 μm. The λ = 2.12 μm image reveals the bipolar nature of the nebula, as well as complex structure near the central star in the equatorial region. The images show an elliptical region of emission which may indicate a ring or a cylindrical source structure. This structure is possibly related to the mechanism which is producing the bipolar flow. The spectra show the nature of several distinct components. The central object is dominated by recombination lines of H I and He I. The core is not a significant source of molecular hydrogen emission. The east position in the equatorial region is rich in lines of ultraviolet–excited fluorescent H2. A spectrum of part of the central region shows strong [Fe II] emission which might indicate the presence of shocks. Subject headings: planetary nebulae: individual: Hubble 12 – planetary nebulae: general – ISM: molecules – ISM: structure – infrared: ISM: continuum – infrared: ISM: lines and bands – molecular processes