Scientists call this protoplanet Theia, and its impact fundamentally changed our world. This artist's impression depicts the collision between Earth and Theia, 4.5 billion years ago. Credit: ...

The results of his study suggest that an object as small as 0.6 meters across could potentially nudge the asteroid onto a ...

Then there are cataclysmic collisions. The Earth's Moon was first created 4.5 billion years ago, likely in a collision ...

New simulations show that Jupiter's massive moon Ganymede was knocked off its axis when it was struck by a roughly ...