Sylvia Else writes:

On 18/02/2011 1:30 AM, Jonathan Thornburg [remove -animal to reply] wrote:
James wrote:
So a lot of movies, TV shows, illustrations, etc., show spacecraft
generating "gravity" via rotating hull sections. In many cases, this
rotating section spins around a stationary central hull.

The question I have for those more knowledgeable in this area than I
is: What is the connection between these two sections? Obviously
there shouldn't be a physical connection between the two hull sections
(right?). But would this mean space enough between the spinnning hull
and the stationary hull for the interior atmosphere to escape? Or is
it sealed somehow?

If you have separate rotating and non-rotating sections (as in, for
example, the movie "2010"), then yes, you need a rotating air-seal
between them. This takes a bit of effort for the engineers, but is
certainly possible.


Do you have any references describing how it could be achieved? I've
looked, and I cannot find anything.

Rotating seals are a well-established technology in many areas, where a
lot more pressure has to be handled than the mere 15psi of sea level
atmospheric pressure -- auto engines, ship propellers... I don't know
of any on the scale of a rotating space ship hull section, but I
wouldn't be at all surprised to learn it's been done. Likewise, getting
electricity through a rotating interface is also well established:
tanks (as in armored vehicles, not as in something to store liquids!)
use metal rings and brushes.