The two halves of the African continent are moving apart at a rate of a few millimeters each year, geologists have calculated.

Where tourists map end and the the fences begin, lie places that aren't marketed, photographed, or casually stumbled into, ...

Jeff Hoffman has floated in the vacuum of space. He’s looked down at our planet from above, seen the whorls of clouds, the vast oceans, and the crowded cities as webs of light. Over five missions -- ...