Titan, the largest moon of Saturn, is the only satellite in the Solar System with a substantial atmosphere. The atmosphere is poorly understood and obscures the surface, leading to intense speculation about Titan's nature. Here we present observations of Titan from the imaging science experiment onboard the Cassini spacecraft that address some of these issues. The images reveal intricate surface albedo features that suggest aeolian, tectonic and fluvial processes; they also show a few circular features that could be impact structures. These observations imply that substantial surface modification has occurred over Titan's history. We have not directly detected liquids on the surface to date. Convective clouds are found to be common near the south pole, and the motion of mid-latitude clouds consistently indicates eastward winds, from which we infer that the troposphere is rotating faster than the surface. A detached haze at an altitude of 500 km is 150–200 km higher than that observed by Voyager, and more tenuous haze layers are also resolved.
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We acknowledge the many members of the imaging team who have assisted in the design of imaging sequences and camera commands and in other vital operational and image processing tasks, in particular N. Martin, E. Birath, J. Riley, B. Knowles, C. Clark, M. Belanger and D. Wilson. This work has been funded by NASA/JPL, the UK Particle Physics and Astronomy Research Council, the German Aerospace Center (DLR), and Université Paris VII Denis Diderot, CEA, AIM, France.
The authors declare that they have no competing financial interests.
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Porco, C., Baker, E., Barbara, J. et al. Imaging of Titan from the Cassini spacecraft. Nature 434, 159–168 (2005). https://doi.org/10.1038/nature03436
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