Radiation in Interplanetary Space, and Space Travel

[Frylock]

I remember reading in some pop-science magazine a few years ago that it may be impossible for humans to go to another planet--even to our closest neightbor Mars--because of the level of radiation that exists in interplanetary space. The article argued that shielding for that level of radiation would render the craft practically unbuildable and unnavigable.

Is this a current view, or has it been superceded, or was it never accepted by anyone knowledgeable in the first place?

[Kinthalis]

Pretty sure the moon is outside the Earth's magnetosphere, so the crafts used to take people there and back were subjected to interplanetary radiation (which, I assume is entirely created by the sun).

[Grey]

There are 2 main radiation sources in space - solar and cosmic.

Solar radiation is mainly protons flung into space by normal solar activity and in great huge gobs by coronal mass ejections and flares. Solar protons can be shielded against by having a storm cellar room to move to in the event a large CME occurs. That does require enough time to move into it of course.

Cosmic radiation is mainly high speed (I mean 99.999% c high speed) charged particles from outside the solar system. Cosmic radiation isn't really a problem, it's the result splash of secondary radiation that occurs when it hits shielding materials. Sort of like shrapnel. It does have a further complication of always being on, somewhat like a constant drizzle of rain.

Some argue it's a show stopper (Committee on the Evaluation of Radiation Shielding for Space Exploration, National Research Council ), some argue it isn't (The Case for Mars, Zubrin).