The danger of solar flares is prevented by Mars' thin atmosphere. High energy cosmic radiation from space, however, easily penetrates the thin Martian atmosphere. However this background cosmic radiation is well below the danger level for plants and animals, including humans.

Although Mars has a thin ozone layer it is not adequate to prevent large amounts of solar ultraviolet radiation from reaching the Martian surface. Astronauts living on Mars will need to take suitable precautions to protect themselves and their equipment from the affects of solar ultraviolet radiation.

One important aspect of this fact is that for spacecraft exploring the outer planets their solar panels lose their effectiveness because of large decreases in the available radiant power from the Sun.

Deep space probes must use other sources of power, such as nuclear power, in order to operate effectively for long periods of time at great distances from the Sun.

On Mars the problem is less severe, but nevertheless the collecting area of solar panels on Mars must be more than twice the area of those required in Earth orbit to achieve the same power gain.