Pluto’s moons

This illustration shows the scale and comparative brightness of Pluto’s small satellites, as discovered by Hubble over the past years. Pluto’s binary companion, Charon — discovered in 1978 — is placed at the bottom for scale. The image illustrates that two of the moons are highly oblate and that the reflectivity among the moons varies from dark charcoal to the brightness of sand. As Hubble cannot resolve surface features on the moons the textures seen here are purely for illustration purposes.