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Comment by mden | Hacker News Reader

If I remember correctly from the presentation, Must claimed radiation was not a significant concern with the exception of things like solar flares. Can anyone comment on the accuracy of that?

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Well, it's not nice out there, but hardly crippling. Cosmic radiation on the ISS is about 150 milliSieverts a year. Interplanetary space could get up to about 800 mSv a year. Not good, but if you can get there in, say, three months, then you've cut your exposure down to what an ISS crewmember would get in a year. The actual danger is solar flares, and for that you'll need some kind of shielding compartment onboard. The ISS is reasonably well-protected from those, but they'll really roast you if you're caught in interplanetary space.

I think Musk mentioned it somewhere in the presentation, but the initial plan for shielding if you're aware that there's going to be a solar flare is to angle the spaceship so that the engines are between the Sun and the crew compartment, and then have everyone packed near the water tank... or something along those lines (it might have been in response to a question in the Q&A time afterwards; I don't remember).

I don't know that they'll have this on the first trips there, but I'd guess that magnetic shields might eventually be a standard component:

http://space.stackexchange.com/questions/3772/how-much-power...

I mean authors have been using that idea for years. The Red Mars trilogy for example (which was an at the time scientifically accurate example of mars colonization).

Each of the stuff for which we read here people jumping and yelling "visionary!" "revolutionary!" "unforeseen breakthrough!" "brand new plan!" "disruptive improvement!", has been dealt with dozen of times in hundreds of SF novels in the last 80 years, which explored all the possible problems (problems are a more exciting matter for a novel than everything-goes-fine-and-as-planned).

But since for most of those people, SF and anticipation is limited to Star-Wars + a couple of other movies/series and super-hero block-busters, they are not aware, and all these stuff appear as genuinely unprecedented technical and sociological thought breakthrough.

Yes, I expect that more advanced active shielding will eventually be developed - particularly since you can detect solar flare events before the radiation arrives.

The challenge with flares is that the radiation can come in from multiple directions, so a cylindrical water container that people can pack into is probably a better defense than just the bulk of the engines.

You need radiation shielding on Mars as well. Unless you live underground, I suppose.

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