An asteroid just flew by Earth about 50% closer than the moon, and we barely saw it coming

The NEOCam telescope is designed to detect larger space rocks of roughly 460 feet or greater. If NEOCam were to launch, a 10-year-long mission would be expected to discover 10 times as many known NEOs of that size or bigger in any previous survey of the sky. ...

from Pocket http://ift.tt/2j5URrR