"Spell checking aint what it used to be."
Posted on 08/01/2005 1:19:26 PM PDT by LibWhacker
Not my idea...read it in a book...but they could use huge tanks of water. Maybe get the water from the moon now that they've found some. Then once your at Mars and have buried your habitat beneath a suitable amount of dirt to block most of the radiation....BOOM....you have enough water to for the mission and beyond. The necessary thickness of water is more than lead....but there will be a use at the end....plus can even the environuts whine about using water?
They will as soon as they have the freedom to do so. That freedom will come with the recognition of private property rights in outer space. Maybe it is still a hobby. So was the West at every stage when it was just fur trapping.
Yuppers.
Why the Tigers version of Aloysius? I know I'm biased, but Bucketfoot Al would look so much better in his White Sox garb. And the A's would admittingly be the most appropiate.
Secondary emissions. I can post more this evening.
That's an interesting comment. I assume you are serious. Why would relativistic speed make a difference?
Never went to West Point or anything, but personally I believe it's an urgent matter of national security. In the short term at least, we should seize cislunar space and deny it to the other major powers.
Give me a few hours, I am up to my a$$ in alligators at the moment. :-)
This is 226 REM, or, assuming that a midsection CAT scan gives you 5 REM, about 45 CAT scans and as far as chest plates, more than 2000.
Typically there are minor blood changes seen at 50 REM whole body, and an acute dose of 300 is life threatening. If this analysis is correct, getting 226 REM over a year represents a serious dose.
Space radiation is difficult to shield. The low energy stuff, slow propons and electrons, get shielded easily. The high energy stuff generates braking radiation (bremsstrahlung) IN the shielding, so at some point doubling the shielding no longer cuts the radiation in half.
This is a factor in Shuttle and space station operations. While nuke plant workers are limited to an occupational dose limit of 5 REM annually and rarely come close to that, the limit for astronauts was increased to 15 so they can continue to fly. Astronauts get lots of radiation compared to nuke plant workers or medical isotope workers.
There are solutions- massive ship with an outer annulus of lunar rock or water is one, as is a lighter craft with a solar sail to reduce transit time.
http://www.space.com/scienceastronomy/radiation_evarm_020716.html
NASA's been thinking about this for a long time, but rarely discusses it as a problem- I'm guessing that they feel they'd lose support from the public given the average American's fear of ionizing radiation.
http://www.sirr.unina.it/Asi/collegamenti/Introduction/NASA/NASA_Strategic_Plan.pdf
They're getting nowhere near relativistic speeds, unless you mean the impacing particles.
Thanks for the reminder of the sorry-*ssed state we find ourselves in these days. I wonder what the Founding Fathers would say.
I think it may be a very real problem too.
I have a couple of old cans of lead paint in my garage. Maybe NASA could paint the spaceship to Mars with it. (hope they like skyblue pink)
Yeah, but earth ain't the same as Jupiter or Saturn.
"Spell checking aint what it used to be."
But, if you're flying though space at 95% of the speed of light, those same cosmic rays will suddenly have an average relative speed of, say, 99% the speed of light wrt your ship. They'll have much greater penetrating power and your old shielding, designed for slow speeds, will no longer be sufficient.
According to Einstein, the laws of physics are the same in any inertial reference frame, that is for anyone going at constant velocity and not accelerating. If so then the velocity of incoming cosmic rays should be independent of the velocity of the platform you are on. If that wasn't the case then you could measure the average velocity of these incoming high speed particles and calculate your actual speed relative to ... to what, that's the problem. There isn't any what. So your velocity can't make a difference.
OTOH, feel free to educate me on what really happens.
Personally, I believe the fact that we're sending billions of $ to people who want us dead -- Arabs, China, take your pick -- is a tad more urgent than claiming a rock in outer space.
The moon obviously belongs to us. As for the cislunar space, wouldn't that be something akin to Columbus claiming the Atlantic Ocean for Spain? Seems like space is something like international waters, except maybe the space above our territory, to some degree.
According to Robert Zubrin in "The Case For Mars," you can shield a small portion of the spaceship with enough lead to create a safe environment. The astronauts would have to reside inside this safe zone for the duration of a solar outburst.
But there's no predicting when a flare up will occur or how long it will last.
It seems totally do-able, but a bit of a pain.
Murdoch Baxter is _no_ Whovian.
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