ANALYSIS: NEWSFLASH: Mars is Toxic
In general, Curiosity's shielding was more effective against particles emitted during solar storms, known as coronal mass ejections, than galactic cosmic rays.
"The galactic cosmic ray, during cruise, is the most dangerous. It's certainly very high energy and it doesn't go away. On the surface, you have some atmospheric protection and obviously it depends on how long you stay on the surface," RAD lead scientist Donald Hassler, with the Southwest Research Institute in Boulder, Colo., told Discovery News.
"It's more difficult to shield against the galactic cosmic rays. The only mission design strategy for that is just to get there as fast as you can. The solar particle events give you more opportunity to potentially shield against them, however, what we're finding is that even these events potentially can contribute significantly to the total radiation dose an astronaut may experience," Hassler said.
During the cruise phase, RAD detected five solar particle events, which accounted for about five percent of the total radiation dose during the trip to Mars.