Pluto Resonance (2015)

Pluto Resonance

T he dwarf planet Pluto is host to at least five known moons - Charon, Nix, Kerberos, Styx and Hydra. Research has shown than three of these satellites - Styx, Nix and Hydra - are tied together by a three-body resonance, reminiscent of that which links the Galilean moons of Io, Europa and Ganymede. The five Plutonian moons have orbital periods in the ratio of 1:3:4:5:6. This means, for example, that the period of the outermost moon is six times the period of Charon, the innermost one, and so on. However, the ratios are not entirely precise, because of chaos in the system. This conceptual illustration uses a clockwork framework linking the orbits of the moons to show that they are intimately connected to each other.
This image was commissioned for the front cover of Nature, 4 June 2015.