How Rivers Flow: Here, Mars & Titan

by | July 30, 2023, 12:00 PM | Solar Systems

This false-color image shows Titan’s second-largest body of liquid, Ligeia Mare, in the moon’s northern hemisphere. Scientists think that rivers flowing into large bodies of liquids like this one should form deltas. Credit: NASA/JPL-Caltech/ASI/Cornell

New research published in the Proceedings of the National Academy of Sciences. Led by Samuel Birch, this work demonstrates a new method for determining the strength of ancient rivers.

From images, we know rivers have flowed on Mars and Saturn’s moon Titan. From living on Earth,… well we have always had rivers.

This new research looks at how both fluids and sediments are carried across a world, how wide and steep a river may be, and then combines these image-based measurements with info on each world’s gravity to estimate the power of the rivers. The calculations can be confirmed here on Earth, and used to look at modern Titan and to try and understand past rivers on Mars.

This research finds that the rivers in Gale crater, home of Curiosity Rover, likely flowed for at least 100,000 years. In Jezero Crater, where Percy explores, the river flowed for at least 1 million years. 

While Titan has a much lower gravity than either Mars or Earth, this research also found that its methane/ethan rivers should be wider and flow along more shallow slopes than rivers with the same flow of water on Mars or Earth. 

It is unclear when we will get the chance to verify the results of this model by directly measuring river flow on Titan, but it is remarkable to think that kind of otherworldly science will one day be possible. 

At least I hope this kind of future exploration will be possible. Right now, a lot of planetary science money and energy needs to be directed at understanding our planet, and that exploration just might have to wait.


Birch, S.P., Parker, G., Corlies, P., Soderblom, J.M., Miller, J.W., Palermo, R.V., Lora, J.M., Ashton, A.D., Hayes, A.G. and Perron, J.T., 2023. Reconstructing river flows remotely on Earth, Titan, and Mars. Proceedings of the National Academy of Sciences120(29), p.e2206837120.