Bobsled?

I can't help but think that vacuum vapor deposition would work for
water. Just put up a 1 km disk as a sunshade, put up you metal track,
and spray water vapor at it. Instant ice. Now, ice at a few Kelvin
is *too* cold, but then again you wouldn't be able to watch the event
without light anyway. So you use mirrors put enough sunlight on the
track to warm it up to whatever the optimal temperature is determined
to be. You can arrange for mirrors which reflect more visible light
than infrared, so you can see the action clearly.

The bobsled would be a cylinder, and it doesn't need to be
streamlined. This is taking place out in the vacuum. It would be
about two and a half metres in diameter, and the same in length.
There would be six runners, spaced equally around the sled. The six
seats would also be spaced around the sled. Why six seats? Because
when I tried to do four, it didn't look right. Kept getting
interference between the seats and the runners. Or they weren't
spaced equally. I'll stick a diagram in FILES. Or maybe not; my
illo is seriously ugly.

Spacesuits would be of the "body stocking" type. The six people who
man the sled grab the push bars and run along the tunnel. I guess the
tunnel would be five metres in diameter, and maybe fifteen metres
long? They are able to run in the weightlessness because they are
braced between the sled and tunnel. The track is generally not a full
tunnel, though, but a, um, "two-thirds pipe." The curves do not, of
course, have to go "downhill," but rather curve in any direction. The
track is so constructed that the sled will sometimes run on two sets
of runners, and sometimes on another two sets of runners, and
sometimes on another two sets...

The length could be, say, two thousand metres. Momentum could not be
gained as the course continued (though speed might be), as there is no
gravitational acceleration. The total momentum of the sled would be
whatever it had when the six men pulled themselves into the sled.