Recently, NASA’s Cassini spacecraft did a fly-by of Saturn and noticed something unexpected on its largest moon of Titan. In the so-called tropical area of the moon, where temperatures rise to a high point of −179 °C (or −290 °F), it appears that there are lakes of liquid methane. This is a surprise to scientists who previously assumed that liquid bodies could only exist near the poles.
Appropriately, this region is known as Shangri La, which appears to have some dark areas which showed up on Cassini’s visual and infrared mapping spectrometer. One of the tropical lakes appears to be the size of Utah’s Great Salt Lake, and features a depth of at least one meter. When asked where these lakes came from, Caitlin Griffith – a Cassini team associate at the University of Arizona – speculated that the lake is being fed from an underground aquifer. “In essence,” she says, “Titan may have oases.”
Knowing about these lakes and where they come from is an important step to understand how weather works on Titan. Whereas the Earth has a “hydrological cycle” (aka. a water cycle), Titan has a “methane” cycle, where methane is circulating rather than water. What’s more, ultraviolet light is able to pierce through Titan’s atmosphere, causing it to break the methane apart on contact. This in turn results in a complicated chain of organic chemical reactions.
These finds are significant for two reasons. For one, it means that life might actually exist on Saturn’s largest moon. The chemical reactions in question involving UV light and methane gas might very well be able to produce organic molecules such as amino acids, the building blocks of life. And second, it could mean the planet would be a suitable candidate for terraforming some day. Liquid methane might not be suitable for humans, but with the right kind of equipment and chemical know-how, it could be converted into water and water vapor without much trouble.
Or we could simply use it as is, pumping it out as fuel. On the other hand, who’s to say we shouldn’t just sit back and watch the life grow. In a few million years, assuming humanity is still alive, Titan may very well join other moons like Europe is producing native life that will emerge from the primordial soups and look out at the stars. And if they then reach out, they might just find us in the mood to share with them. Who knows? It’s the prospects that are exciting!
Source: I09 Magazine.