Saturn's largest moon, Titan, could be the next place where scientists will look for life. Or at least this is the theory that might gain momentum after a lake on the moon's surface has been discovered by the Cassini spacecraft that orbits around Saturn and provides information about the planet and its moons.

The newly discovered lake is filled not with water, but with ethane, the researchers have determined. Looking at the way different portions of the planet's surface reflect light, a method that is called spectrometry, scientists are able to determine the chemical composition of moon's surface. The lake absorbed light of exactly 2-micron waves, the same value for ethane.

What confirmed that the ethane in the lake is in a liquid state, was the fact that the surface absorbed 99.9 percent of the light, something that only a very smooth surface, like a liquid would do. According to the Wired News' website, Robert Brown, a professor at the University of Arizona and one of the leading researchers in the project, said that “For it to be that dark, the surface has to be extremely quiescent, mirror smooth. No naturally produced solid could be that smooth.”

Scientists have long suspected that a hydrological cycle exists on Titan, and this discovery comes to validate this theory. Ethane forms in the higher layers of Titan's atmosphere, where sunlight generates it from methane. The tiny drops of liquid ethane then pour onto the moon's surface and form streams that flow into lakes.

The  chemical composition of the planet's atmosphere cannot support life as we know it, but forms of life that require methane and ethane in order to survive might have at least existed in the moon's early days.