Radiation on mars

First, about oxygen. They will have plenty. It just takes power. Now to radiation...

Don't you wish scientist could make up their minds? They have many different units of measure for radiation levels. This chart gives some good dose comparisons. Video explaining differences.

Then we have this explanation...

The Rad is a unit of ionizing radiation, measuring its energy distribution in air. A Rontgen is similar, but it measures the energy absorbed by an object. A REM is a Rontgen Equivalent Man, so it measures the energy absorbed by a human being.

So that makes it all as clear as mud. I'm going to stick with sieverts (1 sievert = 100 rem.)

In August the Curiosity rover may land on mars giving us a lot more information about the environment. However, the 2001 Mars Odyssey spacecraft gives us a place to start...

Over the course of about 18 months, Mars Odyssey detected ongoing radiation levels which are 2.5 times higher than the astronauts experience on the International Space Station – 22 millirad per day. The spacecraft also detected 2 solar proton events, where radiation levels peaked about 2,000 millirads in a day, and a few other events that got up to about 100 millirads.

1 rad = 1 rem I'm told by google calc. Perhaps once every 9 months they will have to deal with a 2000 millirads (0.02 sieverts) day. Averaging about 22 millirads (0.00022 seiverts) daily. Where does that all fit on the chart? 0.4 Sv over a short period of time produces radiation poisoning. So the maximum recorded over a day would be 20 times less than required in a few seconds to cause radiation poisoning. That's interesting. What about cancer risk? Anything less than 0.1 Sv in a year has no measurable cancer risk according to the linked chart. Add the average dose for a year and you get 0.08 Sv... in other words, no measurable cancer risk. I went into this not knowing what the results would be. I'm amazed.

Sunburn is a humans built in radiation detector. Most people learn quickly how to avoid sunburns. Another article. Radiation Hazards and the Colonization of Mars article.

Research shows that low levels over time are much less dangerous than the same amount quickly. This reminds me of the story that nuclear submarines have to turn down their radiation detectors before they surface or they would all go off as soon as they opened the hatches to the earth's natural background radiation.

Update: Don't get me wrong. Radiation is a hazard that will have to be mitigated. It's just not something they can't deal with. When the radiation alarms go off, they may have to stay home or at the shopping mall they happen to be at, at the time. Like when Los Angeles gets a smog alert.

Update: Magnetosphere to go.

The more we learn about the martian environment (now that a new rover has landed) the less the radiation issue.

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