The planet Mercury was once an active and dynamic planet, according to new evidence from a Nasa spacecraft. Data from the American Messenger probe shows that impact craters on the planet's surface were distorted by some geological process after they formed.
Hubble: Quadruple moons transiting Saturn. The giant orange moon Titan, at the top right is larger than the planet Mercury, and the second largest moon in the solar system after Jupiter’s moon Ganymede. Titan is the only moon in our solar system known to have a dense atmosphere, and the only place other than Earth where stable bodies of surface liquid have been found. Three icy moons are also visible, with Enceladus and Dione at the left and Mimas on the far right.