Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!samsung!mips!ptimtc!nntp-server.caltech.edu!sol1.gps.caltech.edu!CARL From: carl@sol1.gps.caltech.edu (Carl J Lydick) Newsgroups: sci.space Subject: Re: Beanstalk analysis reprise Message-ID: <1991Jun18.155901.13746@nntp-server.caltech.edu> Date: 18 Jun 91 15:59:01 GMT References: <43279@fmsrl7.UUCP> ,<43882@fmsrl7.UUCP> Sender: news@nntp-server.caltech.edu Reply-To: carl@sol1.gps.caltech.edu Organization: HST Wide Field/Planetary Camera Lines: 30 In article <43882@fmsrl7.UUCP>, wreck@fmsrl7.UUCP (Ron Carter) writes: >The terminal velocity of a cable of density 1.7 must be >considered. If the cable is only an inch or two in diameter >and the lengths are not long enough to whip the ends up to >high speed ("range-safety" equipment is indicated!), terminal >velocity will not be high, and damage will be small. I've never seen a proposed beanstalk with that small a cross-section. >> The thread title says "Beanstalk reprise". > >Beanstalks are a class of tether. Weren't you here for the lecture? >> Beanstalks aren't possible given today's technology. I >>agree with you... again !! > >Agreed. However, they are possible given MATERIALS known >today. This is a crucial distinction; we know what to shoot >for, and even many of the physical processes required. A couple of years ago there was a science fact article in Analog Science Fiction/Science Fact that concluded that if we properly understand the mechanisms of chemical bonds, there is no material theoretically capable of the strength needed for a beanstalk on Earth (on the Moon or Mars, yes; on the Earth, no). However, the article concluded that pinwheels would be feasible. Anybody out there got that issue of Analog (or about as good, the issues with the indices in them) and willing to let us know which article I'm talking about? -------------------------------------------------------------------------------- Carl J Lydick | INTERnet: CARL@SOL1.GPS.CALTECH.EDU | NSI/HEPnet: SOL1::CARL