Sailing on seas of methane?

As of November of last year, NASA researchers have started planning a 2015 mission to go sailing on a lake… composed entirely of methane and ethane… over 1300 million kilometers from our planet. This ambitious adventure involves the use of a raindrop-flecked camera placed on a nuclear-powered capsule directed to land on Ligeia Mare – one of the largest lakes on Titan, Saturn’s largest moon.

Scientists have particular interest in Titan as it is the only natural satellite to contain a dense atmosphere, as well as the only celestial object other than Earth for which clear evidence of stable bodies of surface liquid have been found. Titan itself is primarily composed of water ice and rocky material. Prior to 2005, however, the physical characteristics of Titan were largely unknown due to its dense, opaque atmosphere that prevented man-made spacecrafts from gaining visual access to its surface. However, with the arrival of the Cassini-Huygens mission to Titan, scientists discovered the abundant liquid, hydrocarbon lakes in the satellite’s polar regions. Additionally, the spacecraft revealed a mountainous terrain, including several possible cryovolcanoes on the planet’s surface.

Since, the Cassini-Huygens mission arrived in Saturn’s ring system, a much greater understanding of Titan has been gained in the past five years. We now know that the atmosphere of Titan is largely made up of nitrogen and minor components of methane and ethane gas. It’s these hydrocarbon gases that lead to the formation of the orangey clouding and smog that prevented visual access to Titan in years past. Titan’s climate includes wind and occasional rain which contribute to the shockingly similar surface features to Earth, such as: sand dunes and rivers, lakes, and seas of liquid methane ethane, as well as shorelines dominated by seasonal weather patterns. With the existence of liquids and robust nitrogen atmosphere, Titan is considered to be a model of early Earth but at a much lower temperature. It has been cited as one of four bodies in our galaxy that could potentially host microbial extraterrestrial life, or at least, as a prebiotic environment rich in complex organic chemistry.

Thus, for all of these reasons, NASA scientists want to know more. This nuclear-powered “boat” that they are proposing to send to Titan would float about on Ligeia Mare while radioing photos and other data to Earth for a period of about six months. The scientists picked Ligeia Mare in particular as it is over 300 miles wide, which they believe is a big enough target for them to accurately direct their probe straight into the methane sea. The mission is called TIME for Titan Mare Explorer. The probe itself is to be built by the same scientists that created the Beagle 2, the British craft that crashed on Mars on Christmas Day of 2003, as well as the US company, Proxemy Research of Maryland. This British group is being led by Professor John Zarnecki, head of the Centre for Earth, Planetary Space and Astronomical Research at the Open University in Milton Keynes. In regard to the TIME mission he says:

“We want to discover more about Titan's methane weather cycle - like the water cycle on Earth… We want to determine the depth of the lake and if it is murky or clear and what is floating in it, plus look at the shorelines. We'd also want to look for organic materials. Understanding Titan better might also tell us more about whether it is possible for life to develop there."

As I learned from the research I did for my presentation last week, Titan is absolutely swimming with organic chemicals necessary for life, so if the TIME mission could just find some sort of energy source in these methane lakes, the idea of extraterrestrial life could suddenly be much more feasible.