Two NASA astronauts did a spacewalk to remove hardware from the exterior of the ISS.

What we know after American Airlines plane crashes with Black Hawk helicopter in Washington, D.C. Your protein needs change as you get older. Here’s how much you should be eating at every age ...

Throughout its long history, Earth has warmed and cooled time and again. Climate has changed when the planet received more or less sunlight due to subtle shifts in its orbit, as the atmosphere or ...