The good news is that the spacecraft's protective shell, which is similar to the shielding being developed for NASA's Orion deep-space capsule, reduces the exposure inside the spacecraft to about a hundredth of what it was outside the spacecraft. That's according to Don Hassler, the principal investigator for the Radiation Assessment Detector that's installed on the MSL Curiosity rover.
The bad news is that the internal exposure levels measured during MSL's 8-month-plus cruise to Mars would still constitute "a significant contribution to an astronaut's career limit," Hassler said.
