This animated sequence of maps shows varying surface temperatures on Saturn’s moon Titan at two-year intervals from 2004 to 2016. The measurements were made by the Cassini spacecraft. They show heat coming from Titan’s surface at a wavelength of 19 µm, a wavelength at which the moon’s otherwise opaque atmosphere is somewhat transparent. Temperatures have been averaged around the globe from east to west to emphasize the seasonal variation across latitudes. Regions for which there are no data show up as black.
Titan’s surface temperature changes slowly over the course of the Saturn system’s long seasons, which each last 7-1/2 years each. As on Earth, the amount of sunlight received at any location changes as the Sun appears to move north or south in Titan’s sky over the course of the 30-year-long Saturnian year. Cassini arrived at Saturn in 2004 when Titan’s southern hemisphere was in late summer and was the moon’s warmest region. By 2010, shortly after the 2009 equinox, temperatures were about the same across the northern and southern hemispheres, similar to the situation seen by Voyager 1 in 1980, one Titan year earlier.
Image Credit: NASA