Curiosity rover discovers dangerous levels of radiation during Mars transit

While we've learned that radiation levels on Mars are safe for humans, actually getting there in the first place remains a problem. Recent results from Curiosity's Radiation Assessment Detector (RAD) reveal that exposure even while safely ensconced inside a protected spacecraft is dangerously high. Explorers would be bombarded with 466 milliSieverts of high-energy galactic cosmic rays and solar particles during the 253-day transit and the same coming back, with total levels that could exceed NAS...