Infrared Imaging of Planetary Nebulae from the Ground Up
  New ground-based telescopes and instruments, the return of the NICMOS instrument on the Hubble Space Telescope (HST), and the recent launch of the Spitzer Space Telescope have provided new tools that are being utilized in the study of planetary nebulae. Multiwavelength, high spatial resolution ground-based and HST imaging have been used to probe the inner regions of young PNe to determine their structure and evaluate formation mechanisms. Spitzer/IRAC and MIPS have been used to image more evolved PNe to determine the spatial distribution of molecular hydrogen, ionized gas, and dust in the nebulae and halos. 
Joseph L. Hora