GGD 37: An Extreme Protostellar Outflow
  We present the first Spitzer-IRS spectral maps of the Herbig-Haro flow GGD 37
detected in lines of [Ne III], [O IV], [Ar III], and [Ne V]. The detection of
extended [O IV] (55 eV) and some extended emission in [Ne V] (97 eV) indicates
a shock temperature in excess of 100,000 K, in agreement with X-ray
observations, and a shock speed in excess of 200 km s-1. The presence of an
extended pho- toionization or collisional ionization region indicates that GGD
37 is a highly unusual protostellar outflow.
