Mapping and Spectroscopy of the Planetary Nebula NGC 7009 in the Visual
  and Infrared
  NGC 7009 is a fascinating example of a high excitation, elliptical planetary
nebula (PN) containing circum-nebular rings, and FLIERs and jets along the
major axis. We present visual spectroscopy along multiple position angles
through the nucleus, taken with the Observatorio Astronomico Nacional (Mexico);
mid-infrared (MIR) spectroscopy and imaging acquired using the Infrared Space
Observatory (ISO) and Spitzer Space Telescope (SST), and narrow band imaging
obtained using the Hubble Space Telescope (HST). The data show that the
mid-infrared (MIR) continuum is dominated by a broad ~ 100K continuum, and a
strong excess attributable to crystalline silicate emission. The primary peaks
in this excess are similar to those observed in Forsterite and clino- and
ortho-enstatite. We use the ground-based spectroscopy, and ratioing of HST
images to investigate the presence of shocks in the ansae and interior
envelope. It is concluded that line ratios in the ansae may be partially
consistent with shock excitation, although these features are primarily
dominated by photo-ionisation. We also note evidence for shock excitation at
the limits of the interior elliptical shell, and for multiple bow-shock
structures centered upon the ansae.
