Island One, Two and Three

"Combs, Mike" responding to
From: Michael Capriola [mailto:capcartoonist@...]

>Okay, if we postulate a Stanford habitat needs two rings rotating in
>opposite directions,

"Please don't state this as a "need". It is not "necessary", as I
explained in another posting. Simply express it as your preference."

Granted. I posted this before I saw your posting explaining how to avoid
torque effects.

>Also note that it is because we want to avoid unnecessary waste of
>construction materials that the Stanford Torus is considered a better
buy
>than the Bernal Shpere.

"It seems that you're picking your own unique dimensions for the
existing, published designs (your Stanford Torus is a bit smaller in
diameter, though you have two of them, and your Bernal Sphere is a good
deal larger)"

http://www.belmont.k12.ca.us/ralston/programs/itech/orbital/sphere.html
provides a java worksheet for creating habitat stats. The defaults for the
Torus and Sphere are set for populations of 10,000 and 75,000 respectively.
The radius of each would be 830 and 895 meters respectively. Scaling down
the sphere for a population of 10,000 (at 68m^2 per person surface area) we
find we only need a radius of 330 meters. The sphere would rotate at 1.645
rpm.

"O'Neill felt
we had good data supporting that up to 3 RPMs would be OK for most
people, and that 2 was a good compromise."

That answers my question about the coriolis effects. If 2 rpm is not going
to cause problems, then let's go with it.

Now for the big question: how accurate is the belmont site? Here's their
intro:

"PLEASE BE PATIENT WHILE JAVA APPLET LOADS. We will help you with the
calculations. First select the geometric shape of your design using the
radio buttons. Enter the population and physical dimensions (radius, length
etc) of your colony design. Press the button to calculate the corresponding
values. You can then "fine tune" your design by changing the gravity, air
pressure and energy per person. Many default values and calculations are
based on "Space Settlements-A Design Study" by NASA publications even though
any error(s) belong to Web authors. There may be slight differences between
the default values and the calculated values because of rounding off the
numbers. All units are in metrics. See also Regenerative Life Support
Systems for other calculations. For multi-component space settlement
illustrations see Figure 4-2 in Space Settlements."

The intro provides a link to "Space Settlements-A Design Study" by NASA
publications for those of you who do not own a copy, or (as in my case) are
too lazy to pull it off the bookshelf.