A Three-dimensional Map of Titan's Tropospheric Haze Distribution Based on [ITAL]Hubble Space Telescope[/ITAL] Imaging

Abstract

We use Hubble Space Telescope (HST) images of Titan obtained in late 1996 to determine a three-dimensional map of haze optical depth in Titan's atmosphere. These images, taken at six wavelengths from 888 to 953 nm, probe Titan's atmosphere at various altitudes ranging from the surface to roughly 100 km. We solve for the total haze optical depths that best match each HST image and then combine the results from each wavelength into a composite three-dimensional map. The total optical depths due to haze in these maps range from 1.7 in the northernmost latitudes to 2.9 in the southernmost ones. The vertical haze profiles are roughly exponential except for a gap between 20 and 40 km, which may be a result of ethane or methane condensation onto tholins. There is a concentration of haze in the northernmost latitudes between 0 and 15 km above the surface.