Date: Sat, 10 Apr 93 05:25:08 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #448 To: Space Digest Readers Precedence: bulk Space Digest Sat, 10 Apr 93 Volume 16 : Issue 448 Today's Topics: Biosphere II Budget Astronaut (was: Idle Question) Question- Why is SSTO Single Stage Shuttle Status for 04/09/94 (Forwarded) Vulcan? (No, not the guy with the ears!) 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: 10 Apr 1993 08:07:21 GMT From: George William Herbert Subject: Biosphere II Newsgroups: sci.space I don't think that Biosphere II is bad science, and here's why. Science is to some extent about developing accurate models of the real world. In science done about ecosystems, particularly closed ones, there has been a strong tendency to concentrate on trivially simple systems and study the hell out of them, trying to pin down some little cycle to great detail. Bio II said "No, wait, let's take the big picture and see how accurate our big picture models are..." and went out and did it. No, it's not studying the little cycles as well as the smaller experiments can; it _can't_, it's got too many variables. That's not the point, never was, and really doesn't have to be. Bio II is pointing out holes in higher level theories and trying to point new directions for lower-level research. Thinking it's bad science is narrow-minded. It's not incredibly good science either; it's got some holes in it, and a whole lot of variables that they really should have kept better track of. However, it's providing _the_ comparative model for complex close ecosystems analysis. Nobody's done it before, so people tried to put them together from the smaller cycle models and found that it doesn't just work that way. Eventually, when we know everything, we'll be able to do that. But until we do, stepping back and getting a good overall look at the situation is not bad science. -george william herbert gwh@ocf.berkeley.edu ------------------------------ Date: Sat, 10 Apr 1993 06:03:36 GMT From: Henry Spencer Subject: Budget Astronaut (was: Idle Question) Newsgroups: sci.space In article <1q5lr6$j7j@agate.berkeley.edu> gwh@soda.berkeley.edu (George William Herbert) writes: >>... which puts Scout out of the running unless >>you can beat George's weight numbers substantially. (Probably possible, >>but maybe only by fairly radical methods.) > >I'd estimate from other work of mine that a 275-300 kilo vehicle could >be made that would _safely_ sustain life for a few hours and return >the crewman to the surface... >...A person with a heatshield, a re-entry solid rocket, >and a space suit might fit on a scout, but it would be way unsafe >and there would be no systems redundancy. I wouldn't recommend it. The ultimate version of this eliminates the heatshield. Really, it can be done, at least on paper -- you use a specially-designed parachute to increase the surface area for deceleration, and wear a heat-resistant space suit (some of the NASA suit designs have actually been very good thermal insulation, good up to remarkably high temperatures). I expect you'd have to switch to a more conventional parachute for landing. The idea was studied a bit, some years ago. However, I don't know why you'd *want* to use Scout rather than Pegasus, especially when you can be rather more comfortable, and significantly safer, with the extra mass to help. -- All work is one man's work. | Henry Spencer @ U of Toronto Zoology - Kipling | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 10 Apr 1993 07:53:01 GMT From: George William Herbert Subject: Question- Why is SSTO Single Stage Newsgroups: sci.space In article <1993Apr9.150945.7884@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes: >Shooting for minimum operational cost doesn't necessarily mean throwing >away all hint of performance, [...] No, but aerospace engineers tend to draw a blank when presented with the opportunity to lower system cost by making it bigger but cheaper per lb. You'd be amazed what you can get away with if you intentionally design a vehicle for lower performance and with higher margins; I can give you vehicles whose construction & launch cost (ignoring development and profits) is about a dollar a pound. They have initial-payload ratios of 250 to 1 as opposed to 60 to 100 to 1 for current launch vehicles, but they also are a hell of a lot cheaper. [Or hope to be able to do so, sometime soon... at least I can show you how now 8-) ] -george ------------------------------ Date: Sat, 10 Apr 1993 01:52:22 GMT From: "Ralph A.M.J. Wijers" Subject: Shuttle Status for 04/09/94 (Forwarded) Newsgroups: sci.space Question: for those of us who want to get something useful out of reading newsgroups, but have other things to do, it would be quite useful if: 1. People don't post messages in more than one of the groups sci.space sci.space.news sci.astro Don't be afraid to choose, I'm sure most people who might be interested in subjects that could be in any of these groups would subscribe to all three. 2. If people would take some care not to forward the same thing umpteen times to these newsgroups. (I got the shuttle status to which this is a 'reply' 4 or 5 times in sci.space alone). Sorry for the grumpy tone, but I thought it needed to be said. Ralph Wijers ------------------------------ Date: Sat, 10 Apr 1993 05:55:50 GMT From: Henry Spencer Subject: Vulcan? (No, not the guy with the ears!) Newsgroups: sci.space In article stephens@geod.emr.ca (Dave Stephenson) writes: >... Vulcan was supposed to have been >observed by a somewhat dubious 'gentleman' astronomer who kept >his notes on a plank of wood, and used plane as an eraser. This was at a time when many astronomers were "gentleman" astronomers; the only thing that was unusual about Lescarbault was that he persisted in his hobby despite not being wealthy. Leverrier himself visited Lescarbault and concluded that he was no mathematician but appeared to be an honest man and a competent observer; it was through Leverrier's recommendation that he was awarded a medal by Napoleon III in 1860. Unfortunately, with one exception, later attempts to locate the object Lescarbault saw were fruitless. The (possible) exception was that James Craig Watson, at U of Michigan, and Lewis Swift, observing from Pike's Peak, both reported near-Sun objects (Watson thought one showed a disk) during the solar eclipse of 1878. It's reasonably plausible that all three men saw asteroids with eccentric orbits near perihelion. Reference: Willy Ley's "Watchers of the Skies" has a good discussion of the hunt for Vulcan. -- All work is one man's work. | Henry Spencer @ U of Toronto Zoology - Kipling | henry@zoo.toronto.edu utzoo!henry ------------------------------ End of Space Digest Volume 16 : Issue 448 ------------------------------