[X] My Assistant

[Decepticon]

Fans of Ceres will find this article interesting.

The 200 Plus Images are something I would love to get my hands on. Rotation animation Anyone!?


http://www.space.com/scienceastronomy/0509...res_planet.html

[dvandorn]

The problem is, we don't have any real data on how much gravity the human body needs to stay healthy, and for how many hours in a day it needs that gravity.

Some astronauts who suffered mild SAS symptoms on their way out to the Moon felt much better after landing on the Moon. It only took 1/6G for them to feel completely normal and comfortable.

While that's anecdotal information at best, there is still, as of right now, *zero* research data on micro-gravity deterioration effects at 1/6G, or 1/3G, or even 1/20G.

And physiology, like most things in the real world, doesn't follow nice, clean curves. A body can take some conditions a fairly wide degree out of "normal" for quite some time without showing any real degradation. But change the degree just slightly, or change another parameter in addition, and the body hits a "trigger" and starts reacting in ways that are ultimately destructive (loss of bone mass and minerals, etc.).

It's possible that 1/6G might be more than enough gravity for the body to retain normal bone density levels indefinitely. Maybe, though less likely, 1/20G will be enough to do the trick.

It seems to me the *only* way to get this data is by flying spacecraft (in LEO, for ease of the commute) which can be spun at different rates to create different gravity levels (via momentum / centripetal force). Heck you could create different levels at different distances from the rotational center.

Then put people aboard those spacecraft for three months, then six months, then nine months, then a year... do direct observational science on physiological reactions to spending extended periods at whatever gravity strength you want to create.

It wouldn't be all that hard to put together -- just build a central control bus and attach two TransHabs to it. Balance the weight in the TransHabs properly, set the whole thing spinning on the ends of a truss. Put solar panels near the center of the control bus, and keep your consumables down at the ends of the Habs. Cheap (relatively speaking), easy (relatively speaking) little station, which can support (with refurbishment/resupply) a crew of 3 to 6 for up to a year.

Run it for a year at a 1/3G speed, then for a year at 1/6G speed, and then for a year at 1/20G speed. Test crews in all three modes. Get your baseline data.

THEN start planning what kind of spacecraft you need for really long journeys.

-the other Doug