Science Forums 2

[CraigD]

Originally Posted by Pyrotex

I'ts a sad fact, but true. If we take nine months to get the people from Earth to Mars (a standard Holman orbit), the radiation dosage they would absorb would be prohibitively large. It wouldn't kill them outright, but could damage their immune systems, make them feel sick, and possibly lead to cancer. There is no way (currently) to afford enough shielding to protect them during the journey.

One way around this, of course, is to shorten the voyage.

I don’t think “going there faster with little or no extra shielding” is the only solution being considered, or even the most favored at the moment.

I recall that as early as the 1980s, proposals such as Zubrin and Baker’s “Mars Direct” addressed the spacecraft shielding problem with various forms of putting as thick a layer of water between the crew and the Sun, and possibly extra-solar radiation from the whole sky.

By the mid 2000s, I recall reading a lot of criticism of this approach, because it required many times more water than a mission otherwise needed, increasing the mass of the ship beyond what could practically be launched from Earth, even if some in-space assembly was included. An alternative I read of, in articles such as this one, coming from the MSFC’s Space Radiation Shielding Program, was the use of a “reinforced polyethylene” material similar to that used in plastic shopping bags, which was said to have radiation-stopping properties similar to much greater volumes/masses of water.