One of the bigger sticking points in the quest to send humans to Mars has been the potentially deadly radiation levels they would experience. But new information gathered by the Curiosity rover shows that radiation levels on Mars are much milder than feared—about the same as those in low Earth orbit, which is where the International Space Station is located, reports Space. "Absolutely, astronauts can live in this environment," said one Curiosity researcher.
Scientists had worried the planet could have very high radiation levels because Mars lacks a protective magnetic field and possesses an atmosphere that's only 1% as thick as our own. But don't book your space flight just yet: The journey also includes the voyage there and back, and Curiosity experienced radiation levels twice as high as those on Mars' surface during its nine-month trek. Researchers still need to calculate how much radiation an astronaut would be exposed to round-trip before they know whether it's feasible. (More Mars stories.)