Space colonization one step at a time (Step 1)

From: sraj

> If we are to get most of the material from the Moon (hopefully 100%),
> will it not be better to be orbiting the Moon?

One problem is that there are few good choices for lunar orbits. Close orbits are problematic due to the "lumpy" nature of the lunar gravity field. Perturbances grow over time until the low point of the orbit no longer clears mountains(!). The L-1 point is stationary to the moon, and is a lot closer to the moon than the Earth. But I doubt that it's a better location for a lunar-resources-fed manufacturing facility than HEO for the simple reason that the NASA studies were certainly thinking about Lagrange points. They initially favored L-5 for the location of the space facility, then proposed a 2:1 resonance orbit be used instead, before finally settling on a circular 2-week High Earth Orbit.

Regards,

Mike Combs