Date: Wed, 24 Feb 93 05:32:27 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #222 To: Space Digest Readers Precedence: bulk Space Digest Wed, 24 Feb 93 Volume 16 : Issue 222 Today's Topics: >>>>>Question about FRED A response from Anonymous EVA time (was Re: Nobody cares about Fred? ) Getting people into Space Program! ICE Ship McElwaine disciplined! McElwaine disciplined! (somewhat long) PEGASUS QUESTION Reliable Source says Freedom Dead, Freedom II to be dev Reliable Source says Freedom Dead, Freedom II to be developed Wouldn't an earth to moon shuttle be better than fred? 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: Sat, 20 Feb 1993 23:38:31 GMT From: Henry Spencer Subject: >>>>>Question about FRED Newsgroups: sci.space In article <1m3v85INNimc@skat.usc.edu> msmilor@skat.usc.edu (Mark Smilor) writes: > 2) My second question is could a private US corporation do a similar >space station (ie. size, mass, functions, power level, etc) for a significantly >smaller price, like $4 billion ? Space Commerce Corp., a few years ago, estimated $500 million, although I think that was for a somewhat more modest station. That assumed launch by the lowest bidder (that is, on Proton) and hardware built by construction companies (who build things heavier but much much cheaper than aerospace companies). Double it for greater capabilities, double it again for use of US launchers (real competitive bidding would keep costs down, but not to Proton levels), and you've still got a factor of two in hand for overruns. Sounds feasible. -- C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology effect since OS/360. | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 23 Feb 1993 05:26:12 GMT From: Shari L Brooks Subject: A response from Anonymous Newsgroups: news.admin.policy,alt.privacy,comp.org.eff.talk,sci.space,sci.astro In article swaim@owlnet.rice.edu (Michael Parks Swaim) writes: > Call me stupid, but I think that a plainly visible notice that says >"Don't peek" should be enough. (No, I don't think that the SRI notice was >plainly visible.) Just like a "no Trespassing" sign on someone's property edge is enough? Get real. These signs don't work unless accompanied by a threat of violence or prosecution and/or barbed wire, and likewise a "don't peek" notice won't work unless it is accompanied by the lack of perms to look in forbidden directories at forbidden files. -- If you blow fire against the wind, take care to not get the smoke in your eyes. Big & Growly Dragon-monster | bafta@cats.ucsc.edu --------> shari brooks <-------- | brooks@anarchy.arc.nasa.gov The above opinions are solely my own. ------------------------------ Date: 20 Feb 93 19:52:59 GMT From: CLAUDIO OLIVEIRA EGALON Subject: EVA time (was Re: Nobody cares about Fred? ) Newsgroups: sci.space > And maybe I'm wrong, I don't have the figures handy, but didn't the > U.S. log more EVA time in 1992 than did Russia? I remember that sometime ago I read that Americans had more EVA time than Russians (Soviets??). Is it still true??? ------------------------------ Date: Tue, 23 Feb 1993 05:43:28 GMT From: Dave Michelson Subject: Getting people into Space Program! Newsgroups: sci.space In article <76275@cup.portal.com> BrianT@cup.portal.com (Brian Stuart Thorn) writes: > There were 99 X-15 missions, far fewer that qualified as spaceflight. There were *199* X-15 missions.... --- Dave Michelson University of British Columbia davem@ee.ubc.ca Antenna Laboratory ------------------------------ Date: Mon, 22 Feb 1993 22:34:43 GMT From: Nick Szabo Subject: ICE Ship Newsgroups: sci.space gary@ke4zv.uucp (Gary Coffman) writes: >I don't think this could be called an ice spaceship. That has conotations >of a vessel carrying a cargo, not of the vessel *being* the cargo. It can work either way. The cargo can be more ice, or organics, or anything else found on the comet. The ice rocket can also transfer to an asteroid and pick up cargo (eg metal regolith), return astronauts or samples from Mars orbit to Earth orbit, etc. >What you're doing is changing the orbit of an existing ice planetoid >using native reaction materials. If the materials are sufficiently pure, >it would be reasonable to use a steam rocket. If they aren't, a mass >driver would be better... We can get over an order of magnitude more power per unit mass with a thermal system (microgravity mirrors and heat exchangers) than with an electric system (solar cells, magnets and armatures). The processing equipment, which should operate for about a year and produce 10,000 times its own mass in ice, purifies the water via centrifuge, or alternately distills out ammonia or methane (which are better thermal propellants than water, chemically and Isp-wise). It deposits ice to form a dynamically balanced cylinder. So, the ice rocket doesn't much resemble the original comet or asteroid ice deposit. Indeed, we can mass produce ice rockets the size of a Delta rocket or redwood tree trunk, small enough be safely gravity assisted at Earth. >If orbital transfer time is long, as would be expected in the general >case, you might be able to do processing in flight and wind up delivering >*only* processed material at destination. This would likely be the most >efficient case. This is a possibility, but in most scenarios I think it is more economical to take the 10-40% interest cost hit and do the end-user processing in high Earth orbit instead of hauling more equipment all the way out to the comet. For the first mission, this has the advantage that we don't have to launch most of the equipment until the ice is already in earth orbit (if the mission fails, we can cut our losses). As ice propellant becomes cheap from bootstrapping, it becomes much cheaper to transfer equipment around the solar system than to launch it in the first place, so these economies may change as the system matures. -- Nick Szabo szabo@techboook.com ------------------------------ Date: 23 Feb 93 03:44:58 GMT From: Sea Wasp Subject: McElwaine disciplined! Newsgroups: sci.skeptic,sci.space,sci.astro,sci.space.shuttle In article <24861@alice.att.com> ark@alice.UUCP () writes: >It always worries me when someone is stomped on because of what he says, >even if what he says is unadulturated gibberish. Are we so thin-skinned >that we can't just ignore stuff we don't want to see? He's not being stomped on because of WHAT he says (PARDON my MCELWAININAN descent into CAPS), but because he doesn't have the basic decency to post his stuff, BS or not, ONCE, or maybe TWICE, but instead chooses to automatically post it all over the freaking place, and he also never responds to anything sent to him (I've sent him almost a dozen letters). In short, he's being stomped on because he's a deliberate nuisance. Remember: "Posting this will cost hundreds if not thousands of dollars". Considering that I've seen this loon on the nets for over a year and he posts at least three times a week, 3*52 [automated posts take no holidays] = 156 156 * 200 (most conservative interpretation of "hundreds if not thousands) = 31,200 Since his posts are very long, it might be more proper to assume a figure of 1,000 instead of 200 -- in either case, he's eating up an awful lot of other people's money for no purpose. Sea Wasp /^\ ;;; ------------------------------ Date: 20 Feb 93 19:53:34 GMT From: "Russell J. Pagenkopf" Subject: McElwaine disciplined! (somewhat long) Newsgroups: sci.skeptic,sci.space,sci.astro,sci.space.shuttle In article <24861@alice.att.com> ark@alice.UUCP () writes: >It always worries me when someone is stomped on because of what he says, >even if what he says is unadulturated gibberish. Are we so thin-skinned >that we can't just ignore stuff we don't want to see? * SOAPBOX ON * I must agree with you Andrew. Just because *you* (newsgroups in general) don't agree with what someone has to say doesn't mean you have the right to CENSOR him/her. Yes, I agree that sometimes some of the posts can be downright outrageous/annoying, and yes, you might think that this one is too, but just because you don't agree with what I or McElwaine have to say doesn't give you the right to tell me that I can't post this. The newsgroups are really just a reflection of the world around us, and in some ways they are a little more anarchic, but just like the real world you DO have the option to turn away. You *can* press C or N or K if you find the post offensive or tiresome. Should McElwaine have his Internet privileges taken away? I don't believe so. You may disagree with what he has to say, you may be able to prove him absolutely wrong, you may feel offended by what he posts, but he has the right to say what he wants just like you. I grant you that there are limits, but those deal with appropriateness of the newsgroups you post to and the number of groups you post to. These newsgroups are bastions of free speech (free typing ;-) ) and I treasure that immensely. I do not subscribe to all of the newsgroups, simply because there is not enough time in a day to read it all, but if there was I would. I learn more everyday from reading these newsgroups than if I were to attempt to find the information myself. They help me form opinions about issues and I believe they help to make me a better, and more educated person, and THAT is probably the best praise of all for the newsgroups. Yes, even posts like McElwaines' are a part of this. One final note, and this is personal, I felt that some of the replies to what was posted were both rude and obnoxiuos. IMHO, if you're want to flame someone like that e-mail them instead of posting to the net in general, or post information that *shows* us why he is wrong, flaming turns almost everyone off (unless you read *.flame ;-) ). * SOAPBOX OFF * I apologize for the length for the length of this post, but I felt I couldn't stay silent. If you disagree with what I have to say, that's ok you've got your opinions I've got mine, and if you'd like to *discuss* this further lets do it through e-mail. If you vehemently disagree and want to send flames that's ok too, I'll read them and throw them away. If you've read this far, thank-you for listening. -- Russ Pagenkopf "Heading, Sir?" cs__rjp@lewis.umt.edu "Out there. Thataway." cs000rjp@selway.umt.edu "A most logical choice, Captain." ------------------------------ Date: Sat, 20 Feb 1993 23:32:21 GMT From: Henry Spencer Subject: PEGASUS QUESTION Newsgroups: sci.space Organization: U of Toronto Zoology Lines: 14 Sender: news@CRABAPPLE.SRV.CS.CMU.EDU Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU In article n4hy@tang.UUCP (Bob McGwier) writes: >It is MUCH easier to maintain the stability of a vehicle that is already >moving and is effectively gliding that it is to stabilize a rocket in >vertical takeoff from a standing start. This is intuitively obvious to >me at any rate. Only if you're using aerodynamic stabilization (which presumes an aerodynamically stable vehicle -- not all rockets are). Note that two out of three Pegasus stages are essentially non-aerodynamic. If your stabilization is being done by something like engine gimballing, initial velocity or lack thereof is entirely irrelevant. -- C++ is the best example of second-system| Henry Spencer @ U of Toronto Zoology effect since OS/360. | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 20 Feb 93 23:03:23 GMT From: "Phil G. Fraering" Subject: Reliable Source says Freedom Dead, Freedom II to be dev Newsgroups: sci.space BrianT@cup.portal.com (Brian Stuart Thorn) writes: > Oh well, I guess our youth can look forward to building nice > highways in the future, not much else. As someone in the _only_ industry (the energy industry) being targeted with a new tax increace (as if it were immoral, or as if we were doing well during the Reagan/Bush era instead of slowly going out of business), I'd like to say that the highways will be nice, but that's besides the point if all you can drive on them are nice little golf carts.... >------------------------------------------------------------------------- >Brian S. Thorn "If ignorance is bliss, >BrianT@cup.portal.com this must be heaven." > -Diane Chambers, "Cheers" >------------------------------------------------------------------------- One good thing for all the ignerant people, who can at least drive: At least they'll all be able to register at the driver's registration place, or by mail if your car burned oil, natural gas, or coal. Of course, given the stuff I've heard out of Nevada, registration (quote unquote) will be simply another way of enthroning the democrats permanently... -- Phil Fraering |"...drag them, kicking and screaming, pgf@srl02.cacs.usl.edu|into the Century of the Fruitbat." - Terry Pratchett, _Reaper Man_ ------------------------------ Date: Sat, 20 Feb 1993 18:54:53 GMT From: Frank Crary Subject: Reliable Source says Freedom Dead, Freedom II to be developed Newsgroups: sci.space In article <1m3pe3INNsng@access.digex.com> prb@access.digex.com (Pat) writes: >SO if we re-do SSF , how should we do it. >Are trusses inherently more costly and problematic? >certainly it allows larger growth. They also permit more effecient use of solar panels and radiators. However, it isn't clear how necessary this hightened efficiency is to the station as a whole. The truss certainly increases cost and causes stability/dynamic problems. Worse, it substantially increases construction and maintaince cost/effort/time. >Should we look at something made from ETclusters along >with Pre-built modules and inflatable zones? We should certainly _look_ at such a design. I'm not sure if it's the best choice, but it might be. (Skylab was essentially a modified fuel tank, so the idea has been tried sucessfully.) >Should we look at higher altitudes and and steeper inclination orbits? Unless you have some unusual purpose for the station (or want to use Russian/Kazak launch facilities, I'd say no. A higher inclination would substantially increase launch costs, so it would be a bad idea without some substantial benefits to compensate. As for a higher orbit, while it would decrease station keeping fuel costs, it also makes access to the station more difficult. Remember, _something_ has to launch the station, and something will have to regularly transport supplies there and rotate crews. A station in a higher orbit would be far less accessable to the space shuttle. Perhaps the best solution would be that used by the Soviets (and still used by the Russians): Allow the station's orbit to gradually decay, using the station keeping rockets to re-boots the station only once every few months (I.e. so that the station's altitude varies over a substantial range.) Resupply launches and crew rotations can be times to occur when the station is at it's minimum altitude, and therefore most accessable. But since the station does not remain at this accessable altitude, it experiences (on average) far less atmospheric drag, and requires far less station keeping fuel. But the real vital (and politically impossible) part of designing a new station isn't any particular technical detail: The purpose of the station must be clearly defined from the start, and the available funding must be known and remain unchanged. That's really the key to all the technical choices: The advantages and disadvantages of any particular design depend on the intended use of the station, and the moeny available (spending alot of money to make a construction shack/on-orbit repair facility completely vibration free would be a waste, but it would be vital for a micro-gravity materials lab.) If there is/was any single problem with Freedom that stands out, it was the lack of a clear purpose. The design tried to do everything, and satisfy every purpose. As a result, it was very expensive and complex. Later (too late), the design requirments were narrowed to save money, but the basic design was left unchanged. The result is a design that isn't optimized for it's purpose... Frank Crary CU Boulder ------------------------------ Date: Sat, 20 Feb 1993 21:43:05 GMT From: Joe Cain Subject: Wouldn't an earth to moon shuttle be better than fred? Newsgroups: sci.space In article <1993Feb18.185058.3991@bmerh85.bnr.ca> rivan@bnr.ca writes: >In article <1993Feb17.143613.3003@bmerh85.bnr.ca>, rivan@bnr.ca (Robert Ivan) writes: >|> >|> It seems to me that having a earth to moon shuttle would be a far more >|> suitable use of resources. Something that could take a few people and cargo >|> out to the moon and back to earth orbit. Okay, I know that somebody will >|> argue that a space station is needed in between. NASA an most others agree that a space station is virtually useless as a staging point between the Earth and Moon or Mars. I brought this point up with one of the people in Goldin's entourage in Tampa in December. He told me that getting them in the proper position on a return is almost impossible. They thus have no plans to use a space station as an intermediate stop to or from any planet. Joseph Cain cain@geomag.gly.fsu.edu cain@fsu.bitnet scri::cain (904) 644-4014 FAX (904) 644-4214 or -0098 ------------------------------ End of Space Digest Volume 16 : Issue 222 ------------------------------