One billionaire wants to move industry off-world, returning Earth to a pristine state. The other wants to colonise Mars.

April 21 - 28 is International Dark Sky Week, a global celebration of the night sky during which like-minded organizations ...

A gigantic dam, our extraction of groundwater, melting ice sheets and rising sea levels are all altering Earth’s spin. The ...

NASA’s Mars Reconnaissance Orbiter captured an image of the Curiosity rover driving through the Gale Crater. The spacecraft ...