These images were snapped on May 7, two days before Cassini made its third ring crossing as it passed between Saturn and its rings. The images reveal a stunning array of methane clouds on Titan, and may help us understand more about this fascinating moon.
The feathery methane clouds, as NASA calls them, appear in bright bands around the planet in these various images. They were snapped as Cassini flew up to 488,000 kilometers (303,000 miles) from the surface of the moon. The scale of the best images is about 3 kilometers (2 miles) per pixel.
In one image, you can also see some dark patches, which are lakes and seas of hydrocarbons on Titan. This is the only place we know of, other than Earth, with bodies of liquid on its surface – although these bodies more resemble jet fuel than water.
Cassini has no more close flybys within a thousand kilometers of Titan planned – the last one of those came on April 22. But it does have some more opportunities like this to study Titan from afar, leading up to the end of the mission on September 15, when it will be sent crashing into Saturn’s atmosphere.
These methane clouds are particularly interesting. On Earth we might have a carbon cycle, but on Titan there is instead a methane cycle, driven by the evaporation of liquid from its lakes and seas. It takes up to 1,000 years to rain in some locations, and the atmosphere is so thick that it’s difficult to see the surface.
According to NASA, these views from Cassini “are some of the most intensely bright clouds Cassini has observed on Titan, likely due to high-cloud tops. This activity also represents the most extensive cloud outburst on Titan since clouds reappeared at northern mid-latitudes in early 2016.”
Cloud activity is also thought to be increasing in Titan’s northern hemisphere, which is heading towards its summer – summer solstice is just weeks away. The images also reveal dunes of dark dust on Titan.
As for Cassini, it has got 19 more flybys of Saturn to go. This latest one on Tuesday was the first time it has stayed in touch while crossing Saturn’s ring plane. Its next close flyby of Saturn will be on Monday, May 15.