In 2009, a specular reflection from Saturn’s moon Titan established that the low-lying, flat areas on its surface were liquid, when Cassini first noticed this effect. Now this new near-infrared image from the spacecraft’s Visual and Infrared Mapping Spectrometer (VIMS) shows sunglint from Kraken Mare as well as details of islands and other seas in the northern hemisphere. Kraken Mare shows a ring of bright deposits around its edge, interpreted as deposits left when the level dropped through evaporation, like salt flats left around shrinking seas on Earth. Titan’s seas are thought to be liquid methane and ethane.
The image also shows a bright, arrow-shaped clump of clouds over another sea, Ligeia Mare, in a region with the highest resolution data from this flyby. A maze of channels linking the two seas can be seen in this region. The clouds are thought to be methane droplets, possibly falling as rain and replenishing the lakes. This sunglint was bright enough to saturate the VIMS detector and was seen at a greater observation elevation than previous images: the Sun was 40° above the horizon at the time. The brightness means it was visible to shorter wavelengths – 1.3µm – through Titan’s hazy atmosphere. Titan is 5100km across. This false-colour image was taken during Cassini’s 21 August 2014 flyby.