On the heels of SpaceX sending a Tesla Roadster into space, NASA has revealed that it's investigating possibly doing something similar with a submarine.
The agency is zeroing in on Saturn's moon Titan as one of several hot spots in our solar system that may harbor life. The moon, about 80 percent larger than our own, is the only other place in the solar system besides Earth that is home to oceans, rivers, lakes, clouds and even rain. Unlike our own water, however, Titan's surface liquid is composed of a lethal mixture of methane and ethane. Nonetheless, where there is liquid, there's often life — and NASA is eager to see what, if any, bizarre extraterrestrials could be living in Titan's seas.
"Think about life on Earth—we’re all either in water or we’re fancy bags of water,” astrobiologist Kevin Hand of the Jet Propulsion Laboratory told National Geographic in 2014. "On Titan, life in the lakes would be ‘bags’ of liquid methane and/or ethane. That 90 [Kelvin] liquid would be the solvent and then whatever is dissolved into the lakes would be the material that’s used to build the other components needed for life, and to power metabolism."
Creating Titan on Earth
To analyze whether the liquid flowing on Titan might contain alien life, NASA is pursuing the development of an autonomous submarine that could plumb the depths of its seas. The extreme environment of Saturn's largest moon, however, presents a challenge for building the necessary components to survive surface temperatures averaging minus 290 degrees Fahrenheit. To that end, the agency partnered with researchers at Washington State University to create a small piece of Titan here on Earth.
"It’s a crazy experiment, and I never thought I would have had this opportunity," Ian Richardson, an engineer working in WSU’s cryogenic lab, said in a statement. "It’s been a very fun and challenging experimental design problem."
To mimic the conditions a NASA sub might experience, Richardson helped lead a team that built a test chamber containing super-cold liquid methane. They then inserted a small cylinder-shaped cartridge heater to approximate the heat a sub might give off in the mixture. Too much heat and nitrogen bubbles will quickly form in the super-cold liquid, making it extremely difficult for the sub to maneuver with any level of efficiency.
The team also figured out a way to shoot video within the chamber; no easy feat considering the extreme pressure (60 pounds per square inch) and super cold temperatures (minus 300 degrees Fahrenheit). The recording showed ethane-methane rain and snow, similar to the conditions likely present on Titan.
You can see a video produced by NASA for the conceptual sub mission below.
The good news for any future sub cruising Titan's seas is the discovery by WSU researchers that methane and ethane lakes won't freeze until about minus 324 degrees Fahrenheit.
"That’s a big deal,’’ said Richardson. "That means you don’t have to worry about icebergs.”
Should all go according to plan, NASA plans on having a submarine on Titan within the next two decades.
You can see what a landing on Titan might look like, courtesy of footage from the ESA's Huygens probe in 2005, below.