X-Message-Number: 22731 From: Date: Sat, 25 Oct 2003 15:31:02 EDT Subject: Re: CryoNet #22715 Space Space, airships, submarine cargo ships, fusion energy,... are some of the technologies stopped by our society. For the space subject, we need a cheap *and* massive access to space to get out of the mere dream. One solution could be to build 60 miles high towers, made from hydrogen pressurized elements and launch from the top a single stage dumb booster able to produce a 3 - 4 km/s impulsion. A tether could then pick up the payload and bring it into orbit. A nuclear thermal rocket would then bring back the tether center of gravity to its initial position. The NTR motor never come back to Earth, at the end of its useful life it is sent into a very high orbit. If it stops at an early time, nothing fall back because the tether center of gravity is in orbit. The motor may run at low power for a long time giging an acceleration well under one "gee". So the motor may be safe with large operational margins and small, ie: cheap. There is no unobtainium magic material in that scheme, the tower is made of aramide, the rocket may be a simple first stage of a present day booster, the tether is a kevlar-aramide element, the NTR could be a scaled down version of the 40 years old Nerva... The problem is political not technical. Well you could say the same about cryonics for example: Why is it not in universal use? Where is the technical problem? Yvan Bozzonetti. > From: Randall Burns <> > > > Phillip Rhoades wrote: > >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>. > People banking on future technology to produce more > food and other technologies to move people to > space/Mars to solve population problems > are dreaming if they think these are short-term > solutions. > >>>>>>>>>>>>>>>>> > I don't think space is a short-term solution at this > point. <...>. Space development > _could_ have been available now, but Western elites > lost their nerve(which means they obviously need > replacement). As it is now, if we are _lucky_, and we > get some appropriately motivated leadership the next > 10-15 years, we might see some actual development of > space in 25-35 years. I'd expect it to be 40-50 years > before we see a space elevator or the equivalent. > Content-Type: text/html; charset="US-ASCII" [ AUTOMATICALLY SKIPPING HTML ENCODING! ] Rate This Message: http://www.cryonet.org/cgi-bin/rate.cgi?msg=22731