"Jeff Findley" wrote in message
...

In article 13663420.135.1335884487613.JavaMail.geo-discussion-
forums@vbfg3, says...

The announcement by two separate teams backed by highly regarded
scientists and entrepreneurs for asteroidal or lunar mining means
that quite likely there will be a significant market for super
heavy lift.

Why would this require heavy lift? The requirement is to return large
amounts of (valuable) materials to earth, not launch large amounts of
material from earth. This is especially true if you use in-situ fuel
production on a relatively small asteroid (small gravity well). In
order to make such a venture profitable, it would be very nice to lower
launch costs (per pound of payload) but that doesn't require heavy lift
either.


The more I think about it, the more I think the biggest two problems will
be:

1) the environmental impact statement. Right now there's not enough need in
orbit for materials (other than possibly volatiles). But I can't really see
the "Ok, we're going to dump X tons of copper and rare-earths in your
backyard" going over well (and do you dump one large mass or many little
ones!)

2) market collapse. I still can't see this working whre you can bring back
enough materials at current prices to make it worthwhile, w/o collapsing the
market. That said, I'd love to see the numbers.

Personally, I think the best option right now is a minimal mass mission to a
smaller asteroid and then using something like an ion drive to nudge it into
an Earth intersecting orbit and use aerobraking to dump it into a remote
area and using normal earth-bond equipment to break it up.


Jeff

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Greg D. Moore http://greenmountainsoftware.wordpress.com/
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