Preparing lunar surface . . .

Here is a movie about exactly what I'm talking about.

http://www.tethers.com/Cislunar.mov

In their papers, Tethers Unlimited researchers discuss the issue of
the payload descending vertically, but I assumed that they were
discussing the point of reference of the observer and that such an
observer standing on the lunar surface would see the payload
trajectory as described. But then I wondered what about the path of
the payload in its entire orbit not just the approach to the
landing. What if there were obstructions in that path?

In the movie I can see the vertical landing component quite clearly,
but because it is rendered to such a small scale I'm trying to
visualize the orbit of the payload if there were obstructions that
were not near the landing zone.

Take a look at the movie.

--- In spacesettlers@y..., Ian Woollard wrote:
> Um, I did a web search. The tip of the rotovator follows
> a shape called a cycloid. There is an applet that shows a
> cycloid at:
> http://www-groups.dcs.st-and.ac.uk/~history/Java/Cycloid.html
>
> You'll see that the tip comes in vertically; so no
> nuclear weapons to level mountains are required.
>
> victoriatangoman wrote:
>
> > The scenario: There is a rotating lunar elevator that will orbit
the
> > moon and approach the lunar surface five times per orbit. The
> > nearest approach is 50 feet from the surface.
> >
> > The Problem: As the rotating elevator descends it may encounter
high
> > spots in the terrain, even some mountain tops around the
equator.
> > These will have to be cleared to allow a clear path for the
rotating
> > elevator.
> >
> > What are the solutions?
> >
> > 1.) Nuclear exlosive to blow the obstructing mountain top out of
the
> > way. I think this is unlikely considering international treaties
> > prohibiting nuclear weapons in space.
> >
> > 2.) A kinetic energy mass that is fired into the mountain. How
much
> > mass? What velocity? Do we launch the mass from earth? Do we
collect
> > space junk? Is it cost effective to collect space junk rather
than
> > launching inert mass from earth?
> >
> > 3.) A kinetic energy bomb. A combination hit of explosives and
> > impact of the delivery vehicle. How dangerous is it to launch
> > explosives? Is it necessary?
> >
> > 4.) Land a crew and have them plant the explosives strategically
to
> > allow the explosives to work efficiently, where the above
examples
> > would concentrate a lot of energy in a small space and that
energy
> > could remove a lot more material if spread over a larger area,
and
> > if it was buried.
> >
> > So which would be the best way to clear a path for the
descending