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Scientists have published the first 300 days of radiation data from Curiosity on Mars.

Scientists have published the first 300 days of radiation data from Curiosity on Mars.

The results suggest that while the radiation on Mars requires some shielding, most of the worst radiation a traveler would be exposed to would occur during the journey in space to and from Earth. The graph below illustrates this.

Doses of radiation in space


Conscious Choice cover

Now available in hardback and paperback as well as ebook!


From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.

Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.  
Conscious Choice does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.


“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of founder of the Mars Society.


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  • Gotta be one of the lowest risks of a deep space mission. Riding the rocket to orbit is more dangerous than this.

    One of the reasons I stopped listening to any “medical” episodes of The Space Show is that concept of mission risk is totally ignored when discussing radiation hazards of spaceflight. Astronauts are aware of their (theoretical) increased risk of cancer later in life, and yet they choose to fly anyway.

    All the data suggests the radiation boogeyman is a myth.

  • Sayomara

    I think there are more than a few people in history that would say the radiation is more than just a “boogeyman” It is a real risk. Also consider this is logarithmic scale. Yes these bars look close together but ISS to the journey to Mars is still a increase of 2-3 times.

    Maybe that won’t have a long term effect but it would be foolish not to take it into consideration and if we can develop better lighter radiation shielding that makes space fight all that much easier.

  • wodun

    Double the Mars transit bar for a round trip and stack it on the 500 days on Mars bar. Then make the comparison to an ISS visit of the same duration.

    Initially, risk from radiation exposure may be acceptable. It wouldn’t matter for a flags and brags scenario but don’t space cadets want a sustainable pressence off our planet? In the long term we want to mitigate risks like this.

  • Kelly Starks

    So your chart shows about:
    – 5 or 6 times more radiation exposure for 6 months outside Earths magnetic fields in free space on route to Mars vrs in LEO in the ISS
    – 200 times more radiation per month/year on route to Mars then a average person in the US gets.
    – 70 times more radiation per month/year on route to Mars then the legal limits for a radition worker in the US gets.
    – 1/3rd as much per month on Mars as in transit to Mars

    Nasty levels.

  • Kelly Starks

    >.. Double the Mars transit bar for a round trip and stack it on the 500 days on Mars
    > bar. Then make the comparison to an ISS visit of the same duration.

    About `15-24 times the exposure as 6 months on on the ISS.

    That actually seems low?

  • Kelly Starks

    Your talking significant amounts of radiation – and this not a high solar flare period.

  • wodun

    I misunderstood the scale of the graph. I thought stacking the bars would better show exposure over the duration of a round trip but it isn’t an apples to apples comparison.

    Maybe they made the graph this way so it would fit in the report but it isn’t an accurate portrayal of the data.

    To me, it looks like there is a significant increase of exposure. A consistent scale for the graph would show this especially over the duration of a trip to Mars and back.

  • wodun

    One other thing that should be added to the chart is a bar for NASA’s current limit on an astronaut’s lifetime exposure. I don’t know what that is. Maybe a trip to Mars might fall within the lifetime limit?

  • Pzatchok

    Lets just say that the idea of tossing someone into a simple lightweight space capsule for a sight seeing tour around Mars is out of the question.

    I guess they might need a bit more shielding than the ISS provides.

    Or just plan on having cancer a week after getting back to Earth.

  • Kelly Starks

    I looked it up NASA Earth orbiting crew limits are 100 (mSv)/year. The chart shows 2 180 trips to/from Mars, and 500 day stay on the surface would expose astronauts to 1050 mSv. over 860 days, or 2.35 years. NASA limits would be 235 msv over the same time period. Or about 4 and a half times the total limits, but seven times the limits for the transit times.

    And this is with NASA very high rad limits.

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