Saturn’s moon Titan is a pesky moon to study because it has a really thick atmosphere – thicker than Earth’s in fact. But new images have managed to peer below to give us our clearest view yet.
The images were made using infrared data from NASA’s Cassini spacecraft, which came to an end in September 2017 (after a final Titan flyby in April 2017) when it was purposefully slammed into Saturn.
Cassini had an infrared instrument on board, called the Visual and Infrared Mapping Spectrometer (VIMS), and scientists used 13 years of data from it to stitch these new views together.
“This new collection of images is by far the best representation of how the globe of Titan might appear to the casual observer if it weren't for the moon's hazy atmosphere,” said NASA, “and it likely will not be superseded for some time to come.”
Particles known as aerosols in Titan’s atmosphere strongly scatter visible light, which would make seeing its surface with the naked eye near impossible. Infrared, thankfully, can peer through the haze – as can radio waves, which were used to make the initial discovery of lakes and seas of methane and ethane on Titan.
Previous attempts to map the surface of Titan had included a big jump in resolution between images, resulting in kind of patchy looks at this distant alien world. As the data is taken over different flybys, observing different regions at different times, the final images can look a bit odd, containing “seams” like the one below.
“But, through laborious and detailed analyses of the data, along with time-consuming hand processing of the mosaics, the seams have been mostly removed,” said NASA, commenting on the latest images.
And what do they tell us? We can see the moon’s equatorial dune fields, colored in brown in the images. And we can also see that Titan has a complex surface, with a number of geological features.
Titan is the only place other than Earth with known bodies of liquid on its surface – in this case, liquid hydrocarbons, rather than water. It also may have a subsurface ocean, and along with it that tantalizing possibility of life in one form or another.
NASA is currently considering a mission to return to Titan in the 2020s, a proposal to send drones to the surface to fly over its more interesting locales. Based on these latest images, we’d say it’s high time we got serious about a return to Titan sooner rather than later.
