If sending rovers to Mars wasn't enough, Nasa now wants to send submarines to Titan. The space agency has outlined plans to launch the huge structure to Saturn's largest moon by 2040. Titan is unique in the outer solar system in that it is the only one of the bodies outside the Earth with liquid lakes and seas on its surface. Scroll down for video If sending rovers to Mars wasn't enough, Nasa now wants to send submarines to Titan. The space agency has outlined plans to launch the huge structure to Saturn's largest moon by 2040. Pictured is an illustration of what the submarine could look like
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Submarine will head to the largest northern sea, dubbed Kraken Mare, on Saturn's biggest satellite
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It would weigh around one tonne (2,200 lb) and travel at one metre per second (3.6 km/h, 2.2 mph)
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With sea temperature of -290 °F (-179 °C), a radiothermal Sterling generator will prevent it from freezing
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Mission will look for traces of compounds that could give a better understanding of how life began
'The vehicle would observe – and perhaps ultimately exploit - tidal currents in the sea, which follow a cycle once per Titan day, or 16 @placeholder days,' the researchers write in the design proposal.