Two moons passing in the Martian night

The larger of the two moons of Mars, Phobos, passes directly in front of the other, Deimos, in a new series of sky-watching images from NASA's Mars rover Curiosity.

Two moons need names - and SETI wants your help

By tradition, the moons of Pluto have names associated with Hades and the underworld. But there's plenty of possibilities to choose from - and the discoverers of the planet's two tiniest moons are inviting the public to name them.

Were Saturn's moons produced during multiple impacts?

Two professors say that the unusual moons of Saturn could be explained by several large impacts in which several major satellites merged to form Titan.

Pluto spacecraft may have to dodge orbiting rocks

NASA's New Horizons spacecraft - now just two years away from Pluto - is on a riskier mission than previously realized, thanks to the threat posed bty the planet's moons and possible rings.

Cassini snaps new pictures of Saturn and Titan

NASA has released a number of new images of Saturn and Titan snapped by the agency’s Cassini spacecraft.

Uranus tipped over by several collisions

Uranus was knocked on its side not by a single massive collision, as previously thought, but by a series of small thumps, researchers say.