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Fraser
2004-Feb-19, 08:49 PM
SUMMARY: Human travelers to Mars face many challenges. One of the biggest unknowns is exactly what effect radiation from the Sun and cosmic rays will have on the human body for the 1,000 days a journey to Mars might take. If the risk turns out to be high, there are methods that could cut down the amount of radiation humans might receive on the journey. One method could be to build parts of the spacecraft out of plastic, which absorbs radiation 20% better than aluminum; liquid hydrogen, which would be needed for fuel absorbs cosmic rays 2.5 times better.

What do you think about this story? Post your comments below.

Hoore500
2004-Feb-19, 10:31 PM
Plastics are ok if the rocket starts from a geostationary launch base, because won't they melt when the rocket passes through the thermosphere?
To have profit as protection against radiation the hydrogene fuel reservoirs should be constructed in layers around the rocket I supose. A rocket being launched from Earth surface spends most of his fuel on escaping from gravity, thus in any case will be needed a geostationary launch base or not? :blink:
My question is what will happen when the reservoir is half empty, because a rocket spins to avoid warming up. In fact I have a similar question about the stability of an aeroplane when it has half empty reservoirs or one full and one empty, but maybe there is a mechanisme to prohibit this. Especially when it has to turn to the left or right, but that problem never seems to be posed in aviation.

Algenon the mouse
2004-Feb-20, 05:07 AM
Hmmm I would defintely worry about solar flares. If someone was outside making space repairs and the message of one did not get to him in time....

I think the main thing we need to do is watch the cycle of the sun and try and predict when solar flares might occur.

damienpaul
2004-Feb-20, 10:04 AM
A shocking case scenario would be a flare that overwhelms Earth's ionosphere...

John LaCour
2004-Feb-20, 03:04 PM
Originally posted by Algenon the mouse@Feb 20 2004, 05:07 AM
Hmmm I would defintely worry about solar flares. If someone was outside making space repairs and the message of one did not get to him in time....

I think the main thing we need to do is watch the cycle of the sun and try and predict when solar flares might occur.
We do watch. SOHO, HESSI, Ulysses, and a few others I can't remember are all watch the sun and its effect on Earth's atmosphere and magnetosphere 24 hours a day.

Now Solar Flares are the extreme scenario, but the problem we have now is that a human couldn't survive an extended trip ANYWHERE past LEO without getting a leathal dose of radiation. That's why we haven't been back to the Moon, we don't have an L1 lagrange point station between the Earth and Moon, and we haven't sent anyone to Mars. And unless we find a magic bullet system that can completely protect us from radiation, we'll never get a human on Europa or Io either. We could proabably handle Ganymede and Callisto, though.

steva
2004-Feb-20, 08:31 PM
I think that itís too early to talk about human space travel to Mars or Moon or whatever kind of cosmic objects. I donít want to disappoint anyone, but I think that we need to explore more with robots and that kind of stuff.
The conditions on Mars, but not just the solar radiation, are affecting in unimaginable way the future astronauts that will go to Mars. We donít know yet what that effect could be, but it can happen at any time.
Human space flight is something challenging, but it will be, in some day, routine

Nick4
2004-Feb-21, 05:50 PM
I think it is very dangerus to travel in space but it is a good idea to traval and if a solor flare is spoted we can retreat to hevaly armed cabans in the space craft.