Hubble catches rare three moon-parade in front of Jupiter

NASA/ESA Hubble Space Telescope has recently captured a rare triple moon transit of Jupiter.

Hubble took a string of images of the event which show the three of Jupiter's largest moons, Europa, Callisto and Io, in action.

The three moons are known as Galilean moons since they were discovered by the scientist during the 17th century. With orbits ranging from two to 17 days, it's common for at least one of the moons to be seen orbiting the Jupiter. However, the convergence of the three is an occurrence so rare that NASA said it happens only once or twice per decade.

The fourth Galilean moon, Ganymede, was outside the Hubble's view and was not part of the celestial sight.

The moons of Jupiter have very distinctive colors. The smooth icy surface of Europa is yellow-white, the volcanic sulphur surface of Io is orange and the surface of Callisto, which was one of the oldest and most cratered surfaces known in the solar system, is a brownish color.

The images were taken with Hubble's Wide Field Camera 3 in visible light on 23 January 2015.