From: vince@offshore.ai (Vincent Cate) Newsgroups: sci.space.history,sci.space.policy Subject: Re: $5M Moon Rock Stolen From Malta Museum References: <373a0bc9.0405211458.bde154a@posting.google.com> <1ywsc.624$ZM1.488@bignews6.bellsouth.net> <9186edb5.0405250856.eeee6b9@posting.google.com> NNTP-Posting-Host: 207.42.133.252 Message-ID: <9186edb5.0405262211.1423606@posting.google.com> Doug... wrote in message news:... > I think you're *really* underestimating the difficulty of designing and > building a tether that can hold up to the conditions it would encounter, > as well as the difficulty in operating a scoop at the end of such a > tether on what are predominantly rolling and hummocky terrains. When viewed from the surface of the moon the scoop motion will be mostly down and then up. It will not drag sideways at all. Think of the motion of one spoke on a bicycle tire as it comes near the ground and then goes up. When it is nearest the ground it is not moving sideways. Scoop might be the wrong word to use. Probably a spring loaded thing. > Remember, our one and only attempt to deploy a long tether in LEO met > with failure and near-disaster. I'm aware that the conditions in lunar > orbit are different than in LEO, but still, it seems to me that until we > demonstrate something as simple as deploying a 20km tether in LEO, we're > talking out of our asses when speaking of 100km tethers pulling up lunar > materials from orbit. For the lunar stuff I am talking about we would not be using a conducting tether, so no melting of tethers. For the lunar stuff 20 km is long enough. -- Vince