Rivers flow on Saturn's moon Titan, but they are not at all similar to those on Earth or to those that once flowed on Mars.
Scientists do not have many images of the surface of Titan: those taken by terrestrial telescopes are very blurry. It is not so much distance that interferes as the dense opaque atmosphere of Titan, through which little can be seen. There is also an array of photographs captured by the Huygens lander and transmitted by it to the Cassini orbiter: these are the only high-resolution images of the satellite's surface to date.
The samples collected by Huygens during the descent and after, made it possible to draw conclusions about the composition of the atmosphere and soil of Titan. The world turned out to be unfriendly: although the basis of the atmosphere there, as on Earth, is nitrogen, methane is in second place. Clouds and rivers of Titan also consist of it. Where the methane comes from on Titan is still a mystery.
The river channels on all three celestial bodies - Earth, Mars and Titan - are formed in different ways, but the earth remained in this row “superfluous”: its relief, mountains and valleys are constantly changing due to the movement of tectonic plates, and rivers follow the changes in relief. There are no tectonic plates on either Mars or Titan.
On Mars, long-dried rivers run along hillsides, indicating that the latter formed much earlier than water made its way. On Titan, methane river flows have been and continue to be influenced by more recent geological processes - possibly changes in the thickness of the ice crust under the influence of Saturn's gravity.
