The Glenn Research Center has received a grant from NASA to develop the A Titan Sample Return Using In-Situ Propellants mission project. Its goal is to return Titan soil samples using local resources.
Titan is one of the most interesting worlds in the solar system. Its surface conditions are often compared to a young Earth. It is the only one of the satellites with a dense atmosphere. The icy moon’s gas envelope consists of nitrogen and methane. The pressure at its surface is 1.5 Earth’s atmosphere.
Titan is also the only body in the solar system other than Earth that has fluid-filled reservoirs on its surface. However, while on our planet it is water, on Saturn’s satellite its role is played by a mixture of liquid hydrocarbons, mainly methane and ethane. A global ocean composed of a mixture of water, salts and ammonia is also thought to exist beneath Titan’s surface.
All of these factors not only make Titan attractive to science, but also create important prerequisites for a mission that could take samples of its matter and deliver them to Earth. Thanks to its dense atmosphere, the landing should not pose any special problems. Especially since engineers already have experience of a successful landing of the Huygens probe in 2005.
The key stage of the project is takeoff: due to weight limitations, the descent vehicle will not be able to take fuel with it on the return flight, so it will have to be extracted locally. Fortunately, conditions on Titan make this process much easier. To obtain methane, the vehicle will actually need a simple pump, because this gas is already in a liquid state on the surface. The situation with the oxidizer is somewhat more complicated, but still should not be an insurmountable obstacle. Titan’s ground contains a large amount of water ice inclusions, which can be melted using a nuclear source, and then oxygen can be extracted from it.
It is worth emphasizing that so far we are talking about a study of a promising concept and not a formal mission. Nevertheless, its achievements may well find application in the future. In 2027, NASA plans to launch an octocopter Dragonfly on Titan, which will search for complex organic molecules and assess viability. It is possible that its findings will prompt the agency to send the next mission to deliver samples of the satellite’s substance to Earth.