tag:blogger.com,1999:blog-8581401473844438605.post4622087634484723709..comments2024-03-26T19:46:33.565-07:00Comments on Random Walks: The Arithmetic of Interstellar Travel RevisitedJohn Kurmanhttp://www.blogger.com/profile/04607323621206823686noreply@blogger.comBlogger6125tag:blogger.com,1999:blog-8581401473844438605.post-46802805691653466722013-06-20T17:31:47.760-07:002013-06-20T17:31:47.760-07:00"March 9, 1959. Rep. James G. Fulton, Dormont..."March 9, 1959. Rep. James G. Fulton, Dormont, Pa. (R) proposed that Rear Admiral Hyman G. Rickover, so-called father of the nuclear submarine, be asked to help develop a nuclear-powered space rocket". There's your divergence point. By sheer coincidence, Westinghouse Astronuclear Laboratory and Bettis Atomic Power Laboratory were in Fulton's congressional district. He also set up a last minute compromise to save that magnificent white elephant, the Space Shuttle. John Kurmanhttps://www.blogger.com/profile/04607323621206823686noreply@blogger.comtag:blogger.com,1999:blog-8581401473844438605.post-82568627425329213152013-06-20T14:02:59.294-07:002013-06-20T14:02:59.294-07:00My boss is a retired commander and one of Rickover...My boss is a retired commander and one of Rickover's boys. Nuclear and electrical engineer, best boss I've had in 28 years. I can see a fleet of nuclear spacecraft in sync with Kubrick's visual design sensibilities ferrying men and material to and fro. Matter fact, a gritty alternative history serial narrating that would be pretty cool. Rickover's nuclear interplanetary Navy...,CNuhttps://www.blogger.com/profile/14152640304402402884noreply@blogger.comtag:blogger.com,1999:blog-8581401473844438605.post-65226614923408421182013-06-20T12:06:42.224-07:002013-06-20T12:06:42.224-07:00Fucking lawyers. And CYA politicians. Should have ...Fucking lawyers. And CYA politicians. Should have left it to Rickover. He never made a lemon.John Kurmanhttps://www.blogger.com/profile/04607323621206823686noreply@blogger.comtag:blogger.com,1999:blog-8581401473844438605.post-86841834768339681092013-06-20T11:16:45.031-07:002013-06-20T11:16:45.031-07:00Why is it again that with compact fission reactors...Why is it again that with compact fission reactors we're not ion-driving all over the solar system?CNuhttps://www.blogger.com/profile/14152640304402402884noreply@blogger.comtag:blogger.com,1999:blog-8581401473844438605.post-77197814319437905102013-06-20T10:07:42.716-07:002013-06-20T10:07:42.716-07:00Yes, I 'm aware of that. http://engineering.da...Yes, I 'm aware of that. http://engineering.dartmouth.edu/~d76205x/research/shielding/<br />It should work for solar wind, protons, alpha particles and cosmic rays (relativistic nuclei below, say, 500Mev-1Gev in energy), but for things like neutrino flux from supernovae, gamma rays from gamma ray bursters, and ultra-high energy CGRs, magnetic shielding just ain't gonna cut it. Promising alternatives, but still in the pipeline, would plasmonic shielding, or metamaterial cloaks involving wakefield configurations. My guess, if you get that, then you got fusion power, which makes space travel even less likely, as you can do more here on Earth with ultra cheap energy than out in space (cost/benefit wise). The Universe oozes Irony. John Kurmanhttps://www.blogger.com/profile/04607323621206823686noreply@blogger.comtag:blogger.com,1999:blog-8581401473844438605.post-71693825457336197372013-06-19T19:22:26.354-07:002013-06-19T19:22:26.354-07:00Magnetic shielding?<a href="http://physicsworld.com/cws/article/news/2008/nov/06/magnetic-shield-could-protect-spacecraft" rel="nofollow">Magnetic shielding</a>?CNuhttps://www.blogger.com/profile/14152640304402402884noreply@blogger.com