“Space radiation” is the correct term, though sometimes you see “space weather”, to describe the particle environment.
A program used to estimate rad effects is called SpaceRad, after Space Radiation.
This is the sort of dumbing down that made thermodynamics harder than it had to be. The word ‘heat’ should never be used in the context of thermo, but because it is, it gets confusing - specific heat, etc. ‘Thermal energy’ is the correct term, and once you get into that practice, thermo is easy.
Space radiation is a term not unlike what 18th century scientists used the term ‘ether’ for. ‘The ether’ was a scientific term for a very long time until we got specific about what ‘the ether’ meant.
Bodies emitting thermal energy also emit EM radiation. The sun puts out UV radiation. Hydrogen and helium nuclei emit nutrinos. The Van Allen belts emit radiation. Then there are cosmic rays, which is another ‘ether’ like term, since their sources are myriad. At least cosmic rays are understood to originate outside the solar system.
Most of the radiation occuring on Mars is due to the Sun. As such, they could have designed around it sufficiently, but they apparently didn’t.