Astronauts face radiation threat on long Mars trip

[Judi Lynn]

AP/ May 30, 2013, 3:55 PM
Astronauts face radiation threat on long Mars trip

Astronauts traveling to and from Mars would be bombarded with as much cosmic radiation as they'd get from a full-body CT scan about once a week for a year, researchers reported Thursday.

That dose is enough to raise their cancer risk by about 3 percent, but experts caution that there are many uncertainties about the space environment's effects on the body.

As plans for deep space exploration ramp up, radiation is a big concern - from high-energy galactic cosmic rays spewed by distant supernova explosions to sporadic bursts of charged particles hurled by the sun. Earth's magnetic field helps to deflect much of that harmful radiation.

NASA aims to send a crew to orbit the red planet by the mid-2030s. Private outfits like Inspiration Mars - backed by NASA engineer-turned-space tourist Dennis Tito - are seeking volunteers for a Mars flight.

More:
http://www.cbsnews.com/8301-205_162-57586929/

[zipplewrath]

1. Been known for years

There was a tremendous amount of work done in the '70s on deep space living/traveling. All this stuff is "known" and there are potential solutions for all of it. It is sort of frustrating to see this stuff come up year after year as if it is news. We built the "wrong" space station, in the wrong orbit, for the wrong purpose. But some day.....

[longship]

2. Yup! And shielding is massive (heavy).

Probably the best would be water, which they'll have take along anyway. But water has a lot of mass, too. And that old bugaboo the rocket equation doesn't help, because more mass means more fuel, which means more mass, which means even more fuel. You get the idea.

I don't know that anybody has a good solution to this one other than building one honking big spacecraft. Then, how in the fuck do you launch it?

Regardless, I supported human space exploration. But, I would prefer Moon Base Alpha, a permanent settlement on good, old Luna. That is doable now; or at least as soon as we get Ares working.

Alternatives: a permanent space outpost at a Lagrangian point, from which low energy exploration of the solar system can be mounted via the solar system superhighway.

Of course, the latter would require radiation shielding, too. The moon base less so, since the base could be partially underground which shields very well.

R&K

[ladjf]

5. How about parking the shielding at an Earth orbit station, launching the Mars rocket from Earth to

rendezvous with the orbiting station, loading the shielding and additional fuel for the trip to Mars.

That could solve two large problems. Blast off weight from Earth and adequate shielding for the trip.
In space the added weight is manageable.

[longship]

8. I don't see any other way than multiple payloads.

Both from earth, and to and from Mars. Both gravity wells are just too damned steep. Worse yet, Mars doesnt have enough atmosphere to provide sufficient atmospheric braking. Landing on Mars is not easy. Just ask the Russians. Shit! Ask NASA.

The only way out of this is assembling the ship components outside the earth's gravity well. That's fucking tough, too. Then, when you get the thing safely to Mars, what are you going to do? You have to land the thing and still have enough to get off Mars when you're done. Again, no small feat given that it's much more difficult to land on Mars than either the Earth or Luna.

We can solve these issues, but it would be a lot easier to build Moon Base Alpha, IMHO.

[hunter]

3. Until someone builds a fusion rocket, fission will have to do.

It's that, or keep sending robots.

I think robots is the best solution. Eventually they'll have hands, feet, and the brains to use them. Once that happens there's really no need to send flesh and blood people to Mars.

[dimbear]

6. Agreed. In fact, it would be interesting to send over robots programmed to build a

factory that makes robots, and then watch them evolve from a distance.

[Kelvin Mace]

4. I wonder how strong the a magnetic

field would have to be to shield the crew? Also, isn't water an excellent shield? Not as heavy as lead, but the crew would have to have a lot aboard and it would be constantly recycled. Perhaps the tanks could be designed into the walls?

[pokerfan]

7. Tanks in the walls might work for solar flares

but cosmic rays, which tend to be mostly high-energy protons, probably wouldn't be hindered much. Still, some form of magnetic shielding might work:

The idea of shielding spacecraft from harmful cosmic radiation using artificially-generated magnetic fields was once dismissed as unrealistically expensive. But new experiments carried out in the UK show that the technology could be made compact enough, and therefore cheap enough, to protect astronauts on flights to the Moon and Mars.

http://physicsworld.com/cws/article/news/2008/nov/06/magnetic-shield-could-protect-spacecraft

[Kelvin Mace]

11. Perhaps a combination of the two

The water has to be there, why not put it to other uses besides the obvious. But, magnetic shielding seems the way to go. Water could be the "emergency backup".

[pokerfan]

12. Solar flares have the advantage

of being more or less short-lived events plus you also have a warning of at least fifteen minutes or so. You wouldn't necessarily need to shield the entire ship against solar flares, just a storm shelter of sorts, surrounded by water, waste water and other consumables.

[Blue Owl]

9. Bring some weed

[MannyGoldstein]

10. 3% increased chance of cancer?

Sounds like the least of their worries...