NASA's Next Mars Mission Launches Today – Watch it Here Live!

NASA's newest Martian explorer – the Mars Atmosphere and Volatile EvolutioN (MAVEN) spacecraft – is finally ready for lift-off. Currently poised atop an Atlas V rocket at Cape Canaveral in Florida, the Mars-bound orbiter is slated to launch this afternoon at 1:28 pm ET. Live coverage of the launch begins right now! » 11/18/13 8:00am 11/18/13 8:00am

What created such enormous craters on the Moon's nearside?

Earth's moon has been blasted by a lot of space rocks in its 4.5-billion-year history. While these impacts have left a near-uniform distribution of craters across our satellite's surface, planetary scientists have shown that one of its sides – the side that faces Earth – bears significantly larger scars than the… » 11/07/13 12:58pm 11/07/13 12:58pm