Interplanetary GPS Comes a Step Closer [News]

Humans have long used the light of stars to guide them toward their destinations. But in the age of extraterrestrial exploration, it could be the pulses of X-rays from dead stars that guide us through deep space. A NASA team recently built a critical system that will finally let them test such an "interplanetary GPS." A version of the system could be installed on the International Space Station (ISS) as early as 2017.