Nasa has recently announced US$600,000 (£495,000) in funding for a study into the feasibility of sending swarms of miniature swimming robots (known as independent micro-swimmers) to explore oceans beneath the icy shells of our Solar System’s many “ocean worlds”. But don’t imagine metal humanoids swimming frog-like underwater. They will probably be simple, triangular wedges.
Pluto is one example of a likely ocean world. But the worlds with oceans nearest to the surface, making them the most accessible, are Europa, a moon of Jupiter, and Enceladus, a moon of Saturn.
