The outer solar system once seemed like a quiet backwater. But a glut of tiny, strange moons with unruly orbits are coming ...
A researcher has used advanced models that indicate that the formation of Pluto and Charon may parallel that of the Earth-Moon system. Both systems include a moon that is a large fraction of the size ...
Facts about Jupiter's moon Callisto, the third largest moon in the Solar System and the most heavily-cratered object.
Jupiter, Saturn, Uranus and Neptune did not always have their current positions in the solar system. According to the planetary-instability model, they were born a little closer to the Sun and closer ...