Titan: Evidence for seasonal change—A comparison of Hubble space telescope and voyager images
Weaver, H. A.; Tomasko, M. G.; Caldwell, John; Smith, P. H.; Noll, K.; Groth, E. J.; Hasan, H.; Cunningham, Cindy C.; Anthony, David; White, H. P.
Canada, United States
Abstract
Images of Titan were obtained by the Hubble Space Telescope (HST) on 26 August 1990. Comparison with Voyager 1 and Voyager 2 images obtained 10 and 9 years earlier shows that the seasonal hemispheric brightness asymmetry has reversed near 440 and 550 nm wavelengths, with the northern hemisphere now being brighter. An additional, noisy HST image at 889 nm wavelength, for which there are no analogous Voyager data, suggests that the southern hemisphere may have been brighter than the northern at that wavelength in 1990.