An Ancient Collision Fractured Ganymede and Caused it to Shift Off its Axis
Ganymede with the impact site approximately in the centerNASAFour billion years ago, an asteroid larger than the one that ended the age of dinosaurs may have struck the largest moon in our solar system, Ganymede, knocking it off its axis and causing it to crack like an egg.Discovered by Galileo in 1610 while experimenting...