Cosmic Radiation and the New Frontier

Aside from propulsion, one of the biggest challenges to the exploration of deeper space by humans is dealing with radiation exposure.  At this point in our technical development, a trip to Mars might cause astronauts to receive substantial doses (far exceeding regulatory limits for nuclear workers in the USA) of radiation by the time they return home to earth.  This article found a The New Papyrus website gives a great primer on what mankind is up against concerning radiation protection in space exploration.