Date: Fri, 8 Jan 93 05:34:44 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #022 To: Space Digest Readers Precedence: bulk Space Digest Fri, 8 Jan 93 Volume 16 : Issue 022 Today's Topics: *** BUSSARD RAMSCOOP *** Cheap Mars Rocks (was Re: Moon Dust For Sale) Welcome to the Space Digest!! Please send your messages to "space@isu.isunet.edu", and (un)subscription requests of the form "Subscribe Space " to one of these addresses: listserv@uga (BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle (THENET), or space-REQUEST@isu.isunet.edu (Internet). ---------------------------------------------------------------------- Date: 8 Jan 93 07:28:09 GMT From: Henry Spencer Subject: *** BUSSARD RAMSCOOP *** Newsgroups: sci.space In article <1iimffINNm87@gap.caltech.edu> kwp@wag.caltech.edu (Kevin W. Plaxco) writes: >>If we mounted a major effort, we could probably be test-firing antimatter >>rocket engines within ten years... > >Electron-positron annilation generates a couple of gamma ray photons... >Does proton-antiproton anniliation differ? Yes. It generates pions, which decay to muons, which decay to electrons and positrons. Roughly speaking. If you assume that all the electrons and positrons find each other, you end up with gamma rays and neutrinos in the end... but the pions and muons last long enough to be exploited. There *would* be a lot of gamma rays flying around, to be sure. -- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 8 Jan 93 09:07:21 GMT From: K3032E0@ALIJKU11.BITNET Subject: Cheap Mars Rocks (was Re: Moon Dust For Sale) Newsgroups: sci.space,sci.astro,alt.sci.planetary Why buy 1gramm moondust for about $4000.- (or 1 pound for $2'000'000) when I bought 4g Mars rock for $350.- two years ago??? To get the Mars rock I'm talking of down to earth didn't cost a single cent, by the way. The 18kg SNC-meteorit simply fell out of the sky in October, 1962 near Zagami rock in Nigeria. Taking all the known SNC meteorites known, there are hardly more than 100pounds of mars rock available. Thus, $100.000 for a two inch tape of moondust is quite a high price|| I think I'll wait until a *large* lunar meteorite drops down somwhere... So kepp watching out for these space rocks| Herbert ------------------------------ End of Space Digest Volume 16 : Issue 022 ------------------------------