The existence of lakes on Saturn’s biggest moon, Titan, is not news. We have known about lakes near the poles for a while, but scientists have just discovered another lake near the equator. This shallow hydrocarbon lake measures 927 square miles, and there are four small ponds around it.
This is a startling discovery because this lake is full of liquid methane, and scientists speculated that lakes of methane near the equator of Titan would be unstable due to the heat from the Sun as such a latitude. It is often hot enough for the substance to evaporate.
Scientists think that an underground source of methane may be what is keeping the supply in the lake so rich. This could explain the methane-rich atmosphere that Titan maintains.
A water cycle similar to Earth’s could also be occurring on Titan with the methane. It could be evaporating from the tropical lake and then raining into the lakes toward the poles, where it is cool enough for the methane to stay in liquid form.