An asteroid roughly the size of a football field could cause catastrophic damage if it struck a populated area, making planetary defence a problem scientists cannot afford to treat as science fiction.

Add Yahoo as a preferred source to see more of our stories on Google. Animation shows how an asteroid strike may have reshaped Deimos and cloaked it in dusty material. - S. D. Raducan/ESA Mars has two ...

Mars has two tiny moons that lack a confirmed origin story for how they came to orbit the red planet — but new research may explain some of the mysteries surrounding outermost satellite Deimos. Named ...