Flat spots on Saturn's moon Titan may be the floors of ancient lake beds [sciencenews.org]
Peculiar flat regions on Saturn's moon Titan could be the dry floors of ancient lakes and seas. The suggestion, published June 16 in Nature Communications, may solve a 20-year-old mystery [nature.com] [open, DOI: 10.1038/s41467-020-16663-1] [DX [doi.org]].
[...] "Titan is still currently the only other place in the universe that we know to have liquid on its surface, just like the Earth," says planetary scientist Jason Hofgartner of NASA's Jet Propulsion Laboratory in Pasadena, Calif. But the lakes and seas are concentrated near Titan's poles, not the tropics. The regions where the specular reflections show up are bafflingly dry.
[...] The researchers considered whether rainfall, dunes or dry lake beds could be responsible for the reflections, and found that only lake beds explain the timing and locations of the signals. It does rain on Titan, but not frequently enough to explain the reflections, and Titan's dune fields are in the wrong spots. And the specular reflections come from two specific regions that look like other empty lake basins near Titan's poles [sciencenews.org] (SN: 4/15/19).
[...] So if the reflections come from lost lakes, where did the liquid go? One possibility is that it moved from the equator to the poles as part of a Titan-wide methane cycle [sciencenews.org] (SN: 12/8/17). Another is that the liquid evaporated and was destroyed by sunlight striking Titan's atmosphere.
Related: Titan's Flooded Canyons [soylentnews.org]
Tiny Waves Estimated in Titan's Hydrocarbon Lakes [soylentnews.org]
Extreme Methane Rainstorms Appear to Have a Key Role in Shaping Titan's Icy Surface [soylentnews.org]
Acetylene and Butane Could Form Crystals on Titan [soylentnews.org]