[Previous] | [Session 51] | [Next]
H. Roe, J.R. Graham, I. de Pater (UC Berkeley), K. Baines (JPL), S. Gibbard, B. Macintosh, C. Max (IGPP/LLNL), NIRSPEC Team
We present observations of Neptune in the near-infrared (1-5 \mum) obtained with the newly commissioned Near-Infrared Spectrometer (NIRSPEC) at the 10-m W.M. Keck Telescope. The infrared spectrum of Neptune is useful for determining the structure and nature of haze layers and bright 'storm' features in the stratosphere and upper troposphere. Significant variations in atmospheric opacity due to methane and H2 pressure-induced absorption as a function of wavelength allow selective probing of the atmosphere to different depths. Most infrared filters used in imaging cover too wide a spectral range to precisely determine the vertical distribution of hazes and 'storm' particles. Our observations provide both the spatial resolution necessary to separate infrared bright 'storm' features from Neptune's background hazy atmosphere as well as the spectral resolution (R=2000 low-resolution mode, R=25000 high-resolution mode) to selectively probe the atmosphere as a function of altitude. We compare our observed spectra with radiative transfer models to derive haze and 'storm' particle number density and their vertical distribution.
The author(s) of this abstract have provided an email address for comments about the abstract: hroe@astro.berkeley.edu