Curiosity rover finds radiation levels on Mars are safe for humans

It's been three months since NASA's Curiosity rover set foot wheels down on Martian terrain, and now the space agency has divulged what it's learned about radiation on Mars. Marking the first time radiation has been measured from the surface of another planet, preliminary data collected using the rover's Radiation Assessment Detector (or RAD for short) revealed that levels on the ground are similar to what astronauts encounter on the International Space Station. What's that mean for space travel...