From: vince@offshore.ai (Vincent Cate) Newsgroups: sci.space.policy Subject: Re: "The End of Manned Spaceflight Looms Ever Closer" References: NNTP-Posting-Host: 207.42.133.230 "Paul F. Dietz" wrote in message news:... > The OSP is cast as the latest folly: > > http://www.spacedaily.com/news/rocketscience-03zj1.html In that article it says: > "But surely all the technological advances made since > Dyna-Soar/Shuttle/Hermes will allow OSP to be much > faster/better/cheaper," some of you are saying. Whenever anyone says > this, I demand that they name those technological advances. Nobody > is ever able to, since there haven't been any since about 1964, > when NASA's narrow focus on the Moon Race caused them to stop funding > basic rocketry research. As a space tether enthusiast, my answer to this is: 1) Spectra-2000 - very high strength cable for tethers 2) Hall Thrusters - can now get enough high ISP thrust to make reboosting a tether practical 3) The computers and software used for simulation are better now However, I too am amazed at how little progress there has been in areas I would expect NASA to do research in. In particular, I am amazed at the lack of progress in reentry technology. When looking for papers on transpiration, most of them are from back in the 1960s. It seems the DOD has ICBMs that use transpiration during reentry, but details of mass of vehicle, mass of water used, etc are secret (as far as I can tell anyway). It seems NASA has not done a single reentry experiment using transpiration. -- Vince ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ Vincent Cate Space Tether Enthusiast vince@offshore.ai http://spacetethers.com/ Anguilla, East Caribbean http://offshore.ai/vince ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ You have to take life as it happens, but you should try to make it happen the way you want to take it. - German Proverb