Buried "megaripples" — some the size of five-story buildings — are helping scientists piece together the devastation following the impact that wiped out the nonavian dinosaurs.

The planet orbits its star at about 2.5 per cent of the distance of Earth to the sun. It is about a third closer to its star than our solar system's innermost planet Mercury is to the sun - so ...

All the Latest Game Footage and Images from Earth is a 3D Planet A fast shoot-em-up — with a twist. You have 10 seconds to live, flying close to asteroids or destroying enemies grants extra time.