solar power sats

From: spacesettlers@yahoogroups.com
[mailto:spacesettlers@yahoogroups.com] On Behalf Of levi1_ca

> I do not understand the logic of this - is not the geosynchronous
> orbit of the moon at approx 80,000 km this is four times closer
> than the sites at L1 and L2 ( which have their own little orbits
> to correct the mirrors for )

Not sure what you mean by geosynchronous orbit of the moon. My
understanding is that there is no such thing, and the Lagrange points
are the only orbital locations which are stationary with regard to the
moon.

Remember, the moon only rotates once every 28 days.

> and as to being on nearside - a
> satellite on far side would do as well ( except for the loss of
> the view of earth )

In the scenario studied, the satellite (if you're referring to the
mass-catcher) would be at the L-2 point which is above the farside of
the moon. Here's the trajectory:
(http://ssi.org/assets/images/Ch08p150.gif). The Earth is to the left
in this illustration.

If one was launching from a mass-driver on the lunar farside, one would
then place the mass-catcher at the L-1 point between the moon and the
Earth. The only disadvantage there is that (as you hint) the moonbase
associated with the mass-driver would not have direct line-of-sight to
Earth for communications.

> perhaps better as the effect of gravity from
> earth would be smaller. does anyone have any thoughts on this

>From a gravitational dynamics point of view, I don't think there's much
difference between a nearside base launching to L-2 and a farside base
to L-1. I think communications issues were the sole reason for
recommending the former over the latter.

Regards,

Mike Combs