This afternoon JPL released a great new composite photo of Titan, one of Saturn’s moons. Titan is one of the most intriguing satellites in our solar system. It rains, and scientists suspect there are active volcanoes on the surface. Today’s picture shows there are even lakes, including one named for the infamous Kraken. Most of the time it has been cloudy at the North Pole since our probe Cassini arrived in 2004. However, as the north pole begins to enter its summer ,the weather cleared a bit and this September Cassini captured some spectacular images of the lakes on Titan.
Here’s the catch. The weather on titan isn’t based on water. With a surface temperature around -180 C, it’s cold, much to cold for liquid water. Instead the weather’s based on methane, ethane, and other hydrocarbons. (Recently JPL announced it rains plastic, or rather a common ingredient used to make plastic.) The lakes are made up of these hydrocarbons. (While there doesn’t appear to be much free oxygen in the atmosphere, let’s do the smoking indoors all the same, shall we?)
That isn’t to say that there isn’t any water on Titan. Water forms the bedrock on which these lakes sit. Many scientists believe that it occasionally erupts from vents, creating cryo-volcanoes. If true these vents may hint that underneath the surface titan has a buried ocean of water mixed with methane.
Titan’s atmosphere remains a bit of a mystery. Based on the age of our solar system most scientists would have expected Titan’s atmosphere to have eroded by now, blown away by the solar wind. This seems to be the case for other moons of about the same size that orbit Jupiter. What makes this atmosphere intriguing is both the continued presence of hydrocarbons in the atmosphere and the potential for liquid water buried beneath the surface. Of all the planets and satellites which make up our solar system, Titan is the one which seems to hold the most hope of finding life as we know it next door. That said, the hope seems truly slim, almost non-existent really. I believe that someday in the near future, we will know for sure. For now, Titan is one of those places in our cosmos which keeps me looking up.