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Russian Resupply Crash Could Mean Leaving ISS Empty
astroengine writes "In the wake of the Russian Progress vehicle crash shortly after launch on Aug. 24, a chain of events has been set into motion that could result in the decision not to fly astronauts into orbit. If this happens, the ISS will be temporarily mothballed before the end of the year to avoid landing astronauts during the harsh Kazakh winter."
Russia has had fewer astronaut fatailities than the United States, and all of the fatalities Russia has had have been less recent than any of the US's fatalities (those occurring in space, not on the ground). Although it would certainly be a tragedy if people died on a Russian spacecraft, please remember that the reason we now rely on Russian spacecraft is because people died on American spacecraft, and NASA responded by retiring all of the spacecraft involved in the human space program (without developing replacements).
For more fun and to find out how it works, check out the Spin gravity calculator.
In a nutshell, if you can't built a space station half a mile in diameter, don't even bother thinking about it.
Cool page, but it doesn't really agree with you. Note its quote:
In brief, at 1.0 rpm even highly susceptible subjects were symptom-free, or nearly so. At 3.0 rpm subjects experienced symptoms but were not significantly handicapped. At 5.4 rpm, only subjects with low susceptibility performed well and by the second day were almost free from symptoms. At 10 rpm, however, adaptation presented a challenging but interesting problem. Even pilots without a history of air sickness did not fully adapt in a period of twelve days.
This suggests anywhere from 1-2 RPM could probably be workable, suggesting a practical radius of as little as 0.15 miles, or diameter of 0.3 miles (~241/482 meters). Further, this assumes 1g. It's highly unlikely that 1g is necessary.
Mars is one of the most likely targets for extended-duration missions, and has a surface gravity of 0.376g. So let's say 0.4g. This lowers the diameter to as little as 180 meters (~0.11 miles).
If you bring it up to 400 meters in diameter, or less than 1/4th of a mile, you can have 1 1/3rd RPM at better than Mars-equivalent gravity.
Finally, diameter/radius can be a deceptive way of looking at this, since a basic spinning station need not be circular. A first pass need be little more than a room attached to a counterweight with cables.