For instance, what if we really are being visited by aliens from other worlds and they turn out to be aggressive, violent, ...

Mars' innermost moon, Phobos, has long puzzled planetary scientists, who have continually debated whether it's a captured asteroid or formed from debris after a giant impactor struck the Martian ...

A strange substance is hiding on the surfaces of both Pluto and Saturn’s moon Titan, and researchers aren’t sure what it is. Titan’s thick atmosphere means it is extremely difficult to study its ...