Asked by Richard Fawcett
At an average distance of 142 million miles from the Sun, Mars is about 1.5 times as far away as the Earth. This means that the Red Planet receives around half as much light from the Sun than our planet. The Mars Odyssey spacecraft, which carried the Mars Radiation Environment Experiment (MARIE) to measure the levels of radiation for future human spaceflight to Mars, found that radiation levels in orbit around the Red Planet are some 2.5 times higher than measured at the International Space Station. Scientists believe that levels on the surface of Mars might be significantly lower and vary at different locations dependent on altitude. However, while the radiation might be lower, it is still hazardous to us.
Mars does not have much of an atmosphere which means that the ultraviolet light from the Sun is not absorbed and passes through whatever atmosphere there is and reaches the ground whilst some of it will be scattered out of the atmosphere by the gases in the martian skies. While there are global dust storms that rage across the surface of Mars absorbing all of the sunlight and preventing it from reaching the ground, astronauts should not rely on this for full protection since the atmosphere is clear the majority of the time. Nor should they rely on the little bit of dust that is in the atmosphere all of the time and the occasional clouds and hazes that block some of the Sun’s light.
Stepping onto Mars, you would clearly need to wear something that would shield you from these fatal rays and this can be the same material that would be needed for a spacesuit that would assist in your survival in the incredibly thin atmosphere. Another alternative would be to either tunnel underground or take shelter in the lava tunnels carved out by volcanic activity during Mars’ past.
Answered by All About Space contributor Gemma Lavender
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