[Previous] | [Session 53] | [Next]
H.G. Roe, I. de Pater (U.C. Berkeley), C.P. McKay (NASA Ames Research Center)
In the 8 to 13 \mum wavelength range Titan is seen entirely in thermal emission. Depending on wavelength within this range Titan's flux is dominated by a combination of thermal emission from methane (CH4), ethylene (C2H4), ethane (C2H6), and haze. In 1999 we started a monitoring campaign using the Long Wavelength Spectrometer (LWS) on the W.M. Keck I 10-meter telescope to image Titan in seven ~1\mum bandwidth filters between 8 and 13 \mum. In each of these filters we see thermal emission from the haze, as well as thermal emission from one or more the above-listed hydrocarbons. We achieve a diffraction limited resolution of 0.16 to 0.27 arcsec, as compared to Titan's diameter of ~0.8 arcsec. In order to interpret these data we have developed a radiative transfer code utilizing the molecular line parameters in the HITRAN database. We report here early results from this program, including spatially resolved abundance measurements of the haze, ethylene, and ethane. We detect a significant buildup of ethylene around Titan's south pole as compared to other latitudes.