Date: Sat, 20 Mar 93 05:10:48 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #342 To: Space Digest Readers Precedence: bulk Space Digest Sat, 20 Mar 93 Volume 16 : Issue 342 Today's Topics: Aurora spotted ? CD for Pluto Mission Grand Plan How to cool Venus (2 msgs) Just a little tap (was Re: Galileo HGA) LPI, UAz, and ET resources (was Re: plans, and absence thereof) Luddites in space Lunar Arctic, pressure, antifreeze (was Re: Lunar ice transport) Lunar ice transport Need address info / Germany Our Universe not a party Universe? (2 msgs) Predicting gravity wave quantization & Cosmic Noise Small Expendable Deployer System Launch Advisory (was Re: Launch Windows SSTO: A Spaceship for the rest of us Szabos on Spaced [was -- Re: Luddites in space] Why use AC at 20kHz for SSF Power? will dust cool Venus? 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: Fri, 19 Mar 1993 13:10:13 -0500 From: Lawrence Curcio Subject: Aurora spotted ? Newsgroups: sci.space From: PHARABOD@FRCPN11.IN2P3.FR >>Lawrence Curcio writes (Wed, 17 Mar 1993 15:52:29 -0500): >> >>How do you know this isn't an ordinary extraterrestrial UFO ? >> >>-Larry >> >>P.S...... :) > >Because, up to the present time, extraterrestrial UFOs are extraordinary. >This is what the philosophers call "Occam's razor". I am not very fond >of philosophy, and don't understand much in it (but is there much to >understand ?). However, this Occam's razor principle sounds good. If >I understand correctly, its application can be summarized as follows: >when there are an ordinary and an extraordinary explanation for the >same phenomenon, always choose the ordinary one... > >J. Pharabod Well, since the smiley was ignored, it's a good opportunity to be candid. A Mach 8 spy plane is certainly not ordinary either. UFO reports are - that was my original point. It strikes me that the evidence/arguments for the AURORA are no stronger than those for UFO's, yet UFO's are (rightly or wrongly) dismissed out of hand, and the AURORA is (rightly or wrongly) embraced - by the same group of individuals. In fact, now we have a rule that says: 1) If a sighting can be a UFO sighting or an AURORA sighting, it's an AURORA sighting; 2) If the sighting cannot possibly be an AURORA sighting, dismiss it. Don't mistake me for a UFO advocate; I am merely impressed by the social dimension of what passes for common sense. IMHO, we should be consistently skeptical of *ALL* sightings noises and rumors, but allow room in our philosophies for extraordinary things - even Mach 8 spy planes. -Larry C. ------------------------------ Date: 19 Mar 93 19:22:49 GMT From: Arthur Chandler Subject: CD for Pluto Mission Newsgroups: sci.space Someone refresh my memory: what was in the last "message in a bottle" spaceship (I seem to recall a diagram of the solar system, drawings of a man and a woman, etc.), and what form (paper, record, videotape, etc.) did it take? ------------------------------ Date: Fri, 19 Mar 1993 17:59:18 GMT From: Henry Spencer Subject: Grand Plan Newsgroups: sci.space In article 18084TM@msu.edu (Tom) writes: >>>Astronaut should be used if/when necessary, >>>but should not be considered the central goal of the space program. >>I agree with you and there is nothing in the Grand Plan that contradicts >>this. > >What about cancellation of CRAF? Delay of Galileo? CRAF was cancelled because it had overrun its budget massively, and Congress was giving clear signals that this would not be tolerated. This had nothing to do with the manned/unmanned wars. The delay of Galileo was because its launch vehicle was down for bug fixes. The delay was much longer than it needed to be because of safety hysteria, but note that Galileo wouldn't have made its launch window even if it had been on a different launcher -- most of the West's major launchers were grounded in late spring 1986. (There is also the small matter that no other Western launcher *could* have launched Galileo, it being too heavy for the then-operational Titans...) -- All work is one man's work. | Henry Spencer @ U of Toronto Zoology - Kipling | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Fri, 19 Mar 1993 18:04:01 GMT From: Eric H Seale Subject: How to cool Venus Newsgroups: sci.space nickh@CS.CMU.EDU (Nick Haines) writes: >The alternative is to get rid of the CO2 some other way. Chemically, >the best thing to do with it is to turn it into carbonate ions (CO3). >If you bond a carbonate ion with pretty much anything you get a solid >(much of the Earth's crust is formed of carbonate rocks). The easiest >way to get carbonate ions is to get the extra oxygen from water, but >the alternative is to manage some sort of nCO2 -> mCO3 + pC process. I >don't know if this is energetically possible. The really fun part is getting the solid to stay solid (if I'm not mistaken, Venus' current surface temperature is high enough to bake the CO2 back out of carbonate rocks...). My $0.02 Eric Seale #include ------------------------------ Date: Fri, 19 Mar 1993 14:12:19 EST From: Callec Dradja Subject: How to cool Venus Newsgroups: sci.space In article <1993Mar18.082941.10534@nic.funet.fi>, TMakinen says: > > >This removing of carbon from primordial atmosphere as a byproduct of the >chemical processes driven by living organisms is a minor cause to present- >day lack of carbon dioxide in our atmosphere. The main deposit of carbon >dioxide in our planet lies in the carbonate rocks which contain some >100,000 times more CO2 than the atmosphere. CO2 is recycled through >plate tectonics and volcanism. >Teemu Makinen / Finnish Meteorological Institute >teemu.makinen@fmi.fi What you say about the carbonate rocks makes sense but what I do not understand is why the Earth has carbonate rocks and Venus does not. Are carbonate rocks created by some sort of geological process? Both Earth and Venus seem to be geologically active so why the lack of carbonate rocks on venus? It also seems to me that just because most of the carbon dioxide on Earth is bound in carbobate rocks does not mean that this also must be the case on Venus. Perhaps some sort of organic process would still be best. In fact, there are many organisms on earth that produce calcium carbonate, maybe through genetic engineering we could create an organism that produces LOTS of calcium carbonate. I can imagine some sort of dry land coral reef. There is still the problem of water. The choice is either to import water or hydrogen. Both of these options have their disadvantages. Hydrogen, I feel, is the best choice for many reasons. First of all, it has far less mass than water and is thus much easier to transport around the solar system. The next issue is from where we would get the hydrogen and water. With orbits, physical distance is not really the issue, what we need to look at is how close is the water and hydrogen gravitationally? The water, as far as I know, is located in the oort cloud in the form of ice. The orbit of the oort cloud is very different than that of Venus so it would take a great deal of Energy to move the ice to Venus. The hydrogen, on the other hand, is found in the gas giants. I truely do not know which would take less energy to transport. The hydrogen is in a much closer orbit to Venus than the water is but it is also stuck in a pretty deep gravity well. Is there someone out there who can do some math off of the top of their head to figure out which requires less energy, the water of the hydrogen? Another advantage of the hydrogen over the water is that the hydrogen is convenietly found in large quantities all in the sane spot (i.e. a gas giant). The water cannot be so easily collected in that it is whizzing all over the place in the oort cloud. Finally, I prefer the idea of importing hydrogen because it solves some of the problem with the atmosphere. Even with all of the carbon removed from the atmosphere, there is still too much oxygen. Turning this oxygen into water seems more elegant way of solving the problem I would also like to address the solution that one person offered of using nuclear devices to blast the atmosphere out into space. This idea sort of frightens me because such large forces seem sort of difficult to control. I would be afraid that too much of the atmosphere might be blown away. In addition, maybe my thinking is wrong but it seems to me that in the future, if we really start using the resources of our solarsystem, there may one day be a shortage of oxygen. It makes more sense to keep it there in one relatively accessible place than to blast it out into space where it will disperse and be much harder to recover. I am curious to hear what the net readers think of these ideas. Gregson Vaux ******************************************************************** * If all we do is live and die, * Gregson Vaux * * then tell me about the birds that fly. * Penn State University * * If all we did was die and live, * Semitics & English * * would springtime be there to forgive? * GRV101@psuvm.psu.edu * ******************************************************************** ------------------------------ Date: 19 Mar 93 06:07:21 GMT From: Bill Higgins-- Beam Jockey Subject: Just a little tap (was Re: Galileo HGA) Newsgroups: sci.space In article , nickh@CS.CMU.EDU (Nick Haines) writes: > > I fail to understand why people are so _desperate_ to get the HGA > open. Because it's a factor of 10,000 in performance! How hard is that to understand? > Certainly it's insane to suggest jeopardizing the mission merely > in order to get a few more pictures (e.g. the recent suggestion of > an aerobrake manouevre at Jupiter to stress the HGA). It's not insane, just over-eager. JPL's conservative approach is sound: "Let's not risk breaking anything *else* on the spacecraft, because the much-degraded mission we can perform with the LGA alone is well worth doing." Submarines, flying boats, robots, talking Bill Higgins pictures, radio, television, bouncing radar Fermilab vibrations off the moon, rocket ships, and HIGGINS@FNAL.BITNET atom-splitting-- all in our time. But nobody HIGGINS@FNAL.FNAL.GOV has yet been able to figure out a music SPAN: 43011::HIGGINS holder for a marching piccolo player. --Meredith Willson, 1948 ------------------------------ Date: 19 Mar 93 12:22:34 -0600 From: Bill Higgins-- Beam Jockey Subject: LPI, UAz, and ET resources (was Re: plans, and absence thereof) Newsgroups: sci.space,alt.sci.planetary In article <1ocucrINN7j@access.digex.com>, prb@access.digex.com (Pat) writes: > In article |prb@access.digex.com (Pat) writes: > |JPL, Caltech, and universties that work closely with it such > |as U. of Arizona, are chuck full of planetary scientist/geologists. > |There are dozens of quite talented planetary geologists who work > |in the oil and mining industries. JPL and the planetary science > [szabo deleted on Prospecting, plasma science...] > > Wouldn't the lunar and Planetary science institute at JSC be a better > site for this stuff. They already have all the Data on the planets. > And texans know all about drilling for oil. Besides they have been > looking for a mission since apollo ended. Indeed LPI has been involved in "prospecting" for quite some time. (They have organized some workshops where this is one of the topics, and published some relevant material in their books and bulletins.) Your suggestion is good, but Texas planetary scientists are already doing it to a modest extent. The next big event in this field will be the publication of a big thick book summarizing knowledge of extraterrestrial resources and their uses. John Lewis and Mildred Shapley Matthews are cooking it up right now at U. of Arizona Press, and they're almost done. When it comes out we will all have to buy it. Bill Higgins, Beam Jockey | What I want to be Fermi National Accelerator Laboratory | when I grow up: Bitnet: HIGGINS@FNAL.BITNET | "Charismatic Leader Internet: HIGGINS@FNAL.FNAL.GOV | of a Heavily Armed SPAN/Hepnet: 43011::HIGGINS | Religious Cult" ------------------------------ Date: 19 Mar 93 19:04:15 GMT From: Steinn Sigurdsson Subject: Luddites in space Newsgroups: sci.space,talk.politics.space In article szabo@techbook.com (Nick Szabo) writes: mccall@mksol.dseg.ti.com (fred j mccall 575-3539) writes: >I prefer sending people to sending toasters. Typical Luddite comment. The $billions in technology are What use is a toaster if there is no-one there to eat the bread? | Steinn Sigurdsson |I saw two shooting stars last night | | Lick Observatory |I wished on them but they were only satellites | | steinly@lick.ucsc.edu |Is it wrong to wish on space hardware? | | "standard disclaimer" |I wish, I wish, I wish you'd care - B.B. 1983 | ------------------------------ Date: 19 Mar 93 08:26:35 GMT From: Bill Higgins-- Beam Jockey Subject: Lunar Arctic, pressure, antifreeze (was Re: Lunar ice transport) Newsgroups: sci.space In article , jbh55289@uxa.cso.uiuc.edu (Josh Hopkins) writes: > higgins@fnalf.fnal.gov (Bill Higgins-- Beam Jockey) writes: > >>In article <1993Mar18.004000.1164@ke4zv.uucp>, gary@ke4zv.uucp (Gary Coffman) writes: GC>>> I was suggesting a system that is *self pumping*. The solar heating of GC>>> the pipe during lunar daytime boils the water and the system "percolates" GC>>> via a set of one way check valves toward the equatorial base. > BH>>Cute idea, Gary, but if it could be made to work, it would work BH>>only six months a year at best. > JH> First I want to clear up one thing that might be confusing. The problem is JH> with standard night/day cycles (in which the days add up to six months) JH>rather JH> than a single six month night as you would expect at a terrestrial pole. I'm JH> sure Bill know's this but other readers might be confused. You credit me with more subtlety than I deserve, Josh. The Moon's "Arctic Circle" is very small since its inclination to the ecliptic is only 1.5 degrees. Nevertheless there *is* a small region where it'll be night six months at a time. And this happens to be where the ice is coming from. And it happens to be the place in Gary's system where he needs the most pressure and energy. This is not insurmountable but it screws up the elegance of Gary's idea. > Secondly, I don't think it should be too hard to isolate the pipeline from the > surface to drastically cut down on the heat loss at night. The pipeline is > then essentially radiating to vacuum. Given the high heat capacity of water, > and > the two phase changes you'd have to go through before the water would freeze, > it seems to me that you could keep the pipeline running for at least part of > the Lunar night. Good point, but there is a flip side to your argument-- we gotta wait until some time *after* dawn for the pipes to warm up again! Thus there is a corresponding time at the beginning of the day when you can't operate. Remember Henry's assertion that the temperature is a constant 255 K underground? That nice steady thermal environment is mighty attractive. >If I had more spare time I'd pull out my steam tables and > plug a few numbers. I looked at my office copy of the CRC (36th edition, 1954-55. Hey, it was cheap!). The melting point of ice is depressed to 253 K by a "pressure" of "2042 kg/cm^2." This was in the happy carefree days before people cared about getting their units straight. Let's see... I guess this is 9.8 N/cm^2 times 2042, eh? Just over 20kN/cm^2, or 2E8 N/m^2... is this a Pascal? Oh, here's a conversion table... 2042 kg/cm^2 is 2110 atmospheres. Wow. This is a gauge pressure, too, so better throw in an extra 1 atm for the Moon. (-: I was going to suggest lowering the melting point of the water in the pipeline by operating it at a high pressure. I think this is a bit *too* high, though. (Homework problem: what is the total stored energy in 0.25 Moon circumference of pipeline at 2111 atmospheres? Lunar radius is 1738 km at the equator. Let's say the pipe radius is 10 cm. Problem 2: How thick do the walls have to be for an iron pipe? For aluminum?) Lowering the melting point with an antifreeze solution is a better idea. What would be a suitable antifreeze we could derive from lunar materials? You're allowed to use CO2, CH4, and other stuff in comets, since we are assuming we've found a lunar water-ice deposit and these chemicals would be mixed in. Bill Higgins, Beam Jockey | Comet Swift-Tuttle is Fermi National Accelerator Laboratory | Mama Nature's way of Bitnet: HIGGINS@FNAL.BITNET | saying it's time to Internet: HIGGINS@FNAL.FNAL.GOV | get off the planet. SPAN/Hepnet: 43011::HIGGINS | --Dale Amon ------------------------------ Date: Fri, 19 Mar 1993 18:08:55 GMT From: Henry Spencer Subject: Lunar ice transport Newsgroups: sci.space In article <1993Mar19.160848.22518@pmafire.inel.gov> russ@pmafire.inel.gov (Russ Brown) writes: >>We only have a few data points, but they're all within a degree or two >>of 255K. The variation is from site to site -- the temperature at any >>particular site is absolutely constant at that depth. > >Usenet works! > >Keihm and Langseth reported (1973 Apollo 17 data) a mean temperature of >256K at 1.3 metres; little variation would be expected at that depth... Usenet works to the extent that it is backed by good information. :-) It's not an accident that the number is spot-on: I looked it up in Lunar Sourcebook before posting. L.S. has graphs of temperature and variation versus depth for all the Apollo heat-flow probes. -- All work is one man's work. | Henry Spencer @ U of Toronto Zoology - Kipling | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 19 Mar 1993 14:57:14 -0500 From: "Michael K. Heney" Subject: Need address info / Germany Newsgroups: sci.space I'm working on a project for SpaceCause, and I need to get some address information for two individuals associated with the German space industry. What I need is a title (if known), business address (correct to get mail from US to Germany), and phone numbers (again, assume US calling point.) The names I need info for are: Jorgen Blum DLR Cologne and Hans Hoffman ERNO (or its successor organization?) Bremen Replies via e-mail would be appreciated. Thanks much. ---- Mike Heney | Senior Systems Analyst and | Reach for the mheney@access.digex.com | Space Activist / Entrepreneur | Stars, eh? Kensington, MD (near DC) | * Will Work for Money * | ------------------------------ Date: Fri, 19 Mar 1993 02:12:01 GMT From: Jeff Bytof Subject: Our Universe not a party Universe? Newsgroups: sci.astro,sci.space,sci.physics In article dpalmer@csulb.edu (Dave Palmer) writes: >Those of us who grew up reading science fiction have become comfortable >with the idea of rapid space travel via some sort of "space warp." That >is, a technology for warping space or passing through wormholes, >hyperspace, or whatever. I think we've just tended to assume that someday >we will discover how to do this. But what if no such mechanism is >possible? Or, if it is, but requires impractical energies, or has some >other practical limitation? Maybe if space warps and wormholes are discovered, that will naturally lead to access to other "universes". These other universes might be a hell of a lot more interesting than this one, perhaps explaining the lack of "party life" in this one. -rabjab ------------------------------ Date: Fri, 19 Mar 1993 17:49:16 GMT From: "John S. Neff" Subject: Our Universe not a party Universe? Newsgroups: sci.astro,sci.space,sci.physics In article rabjab@golem.ucsd.edu (Jeff Bytof) writes: >From: rabjab@golem.ucsd.edu (Jeff Bytof) >Subject: Our Universe not a party Universe? >Date: Fri, 19 Mar 1993 02:12:01 GMT >In article dpalmer@csulb.edu (Dave Palmer) writes: > >>Those of us who grew up reading science fiction have become comfortable >>with the idea of rapid space travel via some sort of "space warp." That >>is, a technology for warping space or passing through wormholes, >>hyperspace, or whatever. I think we've just tended to assume that someday >>we will discover how to do this. But what if no such mechanism is >>possible? Or, if it is, but requires impractical energies, or has some >>other practical limitation? > >Maybe if space warps and wormholes are discovered, that will naturally >lead to access to other "universes". These other universes might be a >hell of a lot more interesting than this one, perhaps explaining the >lack of "party life" in this one. > >-rabjab A practical problem, seldom covered in science fiction stories about traveling at near the speed of light, is the radiation hazard. If we assume v = 0.9c and N = 1 hydrogen atom per cc for an average density in interstellar space the flux of ~ 100 MeV protons will be about 2e10 per sq cm of effective area of spacecraft. Hardening equipment to work under such conditions will be a big challenge, and keeping people alive will be even more difficult. ------------------------------ Date: Fri, 19 Mar 1993 17:48:22 GMT From: "Thomas E. Smith" Subject: Predicting gravity wave quantization & Cosmic Noise Newsgroups: sci.space,sci.astro,sci.physics,alt.sci.planetary >In article <1993Mar18.150800.29635@aio.jsc.nasa.gov>, tes@motif.jsc.nasa.gov. (Thomas E. Smith) writes: >> same time (I forget if gravity travels the speed of light, or is instantly >> propagated) > >wedemeier@vxdesy.desy.de writes: >Instantly propagated????? - Are you nuts? :-) >Then we wouldn't get waves and that would screw up the relativity theory! > >Volker Ok, you're right about gravity travelling the speed of light, but I don't see why that is required to produce the kind of gravity waves we're trying to detect. What I think they are trying to detect are things like an extreamly massive black hole being orbited by a neutron star, for example. If the black hole is so much more massive than the neutron star, it will hardly move. So this kind of thing happens: __NS__ ______ ______ / \ / \ / \ | BH | NS BH | | BH | \ / \ / \ / ---- ---- -NS- Earth Earth Earth Weak Medium Strong Force Force Force This would produce a weakening and strengthening of the gravitational wave from the black hole & neutron star system. I chose the large masses so that maybe they could be detected here. This is should produce the very weak, and very long waves that they are trying to detect. It seems to me that if they were trying to detect gravitons, those would be extreamly short. I do agree with you that gravity travels the speed of light, but in this case, why does it matter? In what case would it matter? -- ------------------------------------------------------------------------------- | Living on Earth may be expensive,| Tom E. Smith | ._________ | | but it includes an annual free | tes@gothamcity.jsc.nasa.gov| |= (0_, \ \ | | trip around the Sun. | | |= |0 ` / | | ------------------------------ Date: 19 Mar 93 19:05:00 GMT From: wingo%cspara.decnet@Fedex.Msfc.Nasa.Gov Subject: Small Expendable Deployer System Launch Advisory (was Re: Launch Windows Newsgroups: sci.space In article , nickh@CS.CMU.EDU (Nick Haines) writes... >So what happened? > >Nick Haines nickh@cmu.edu The Launch of the GPS Block IIR/ SEDS 1 experiment was postponed at 8:30 pm last night due to excessive (40 mph) winds at ground level at the cape. The launch has been re-scheduled for the same time (11:00) pm tonight. I will post the results as soon as I know about them Dennis, University of Alabama in Huntsville ------------------------------ Date: Fri, 19 Mar 1993 18:04:46 GMT From: Henry Spencer Subject: SSTO: A Spaceship for the rest of us Newsgroups: sci.space In article <1993Mar18.013020.1791@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes: >Henry says that DC-Y will mass 800,000 pounds, and that 700,000 >pounds of that will be fuel. He further says that LOX is $5 a >pound and represents the bulk of the weight. So ignoring the >hydrogen's extra handling costs, fuel for a DC-Y flight costs >$3.5 million dollars... Gary, how do you ever run a successful business if you can't read any better than this? :-) First, and relatively minor, I never quoted any figure for DC-Y's mass. If you re-read my writeup, you'll find that it uses that number purely as an arbitrary example, when discussing the implications of mass ratios. Second, and more serious, I quoted LOX at five **CENTS** a pound, not five dollars a pound. -- All work is one man's work. | Henry Spencer @ U of Toronto Zoology - Kipling | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Fri, 19 Mar 1993 18:27:02 GMT From: fred j mccall 575-3539 Subject: Szabos on Spaced [was -- Re: Luddites in space] Newsgroups: sci.space,talk.politics.space In szabo@techbook.com (Nick Szabo) writes: >mccall@mksol.dseg.ti.com (fred j mccall 575-3539) writes: >>I prefer sending people to sending toasters. >Typical Luddite comment. The $billions in technology are >merely toasters, the engineers and techs who make them >merely toaster-makers, and the only people that count >are the people who have accomplished almost nothing >for the space program, the astronauts. I suggest you learn how to read and then look up the definition of "Luddite", monkey boy. I also suggest that if you elect to rant and rave in the outrageous fashion that you do that you should expect a certain amount of exaggerated rhetoric in return. I further suggest that if you want to engage in telling people what they think that you should learn something about the process of thinking first. If that is your interpretation of what I said, I can see why you have the opinions that you do. Your problem is obvious. If I want your stupid opinion, I'll read it in your entrails, Nicky. As for your misinformed opinion about what I said (which strikes me as pretty far from reality -- but that's nothing new for you), please feel free to take your opinion and do something anatomically creative and quite unlikely with it. [Nothing like responding in kind to an idiot, hey, Mr Szabo?] -- "Insisting on perfect safety is for people who don't have the balls to live in the real world." -- Mary Shafer, NASA Ames Dryden ------------------------------------------------------------------------------ Fred.McCall@dseg.ti.com - I don't speak for others and they don't speak for me. ------------------------------ Date: 19 Mar 93 12:05:52 From: Steinn Sigurdsson Subject: Why use AC at 20kHz for SSF Power? Newsgroups: sci.space In article schumach@convex.com (Richard A. Schumacher) writes: Oh, nuts. So a 20kHz power system saves 2,000 pounds, huh? Assume it costs $3,000 per pound to launch. Spend $6M on the extra weight of a 400 Hz system, and 20 minutes later you're in orbit. Instead, NASA spent $20M and two years on 20 kHz system development, and has a lot of paper sitting on desks. If it were to become standard and used on other systems it would save a lot more weight in the long run. When you're about to put up the first major piece of infrastructure in space, one that might in principle be expanded, it becomes sensible to consider the possibility of whether a new standard for such things as power systems makes sense in the long run. One of the most frequent complaints here against NASA is that they don't consider new technologies that might lower costs in the long run and don't experiment with different concepts. Yet, when they do and it doesn't work out they are chastised (often by the same people) for wasting money when they could have been using old and tried technology, and using the magic of 20-20 hindsight it becomes "obvious" that the new concept tried wouldn't work. Pah! As for the difficulty of shielding scientific instruments from 400 Hz noise: some EE better go tell those poor fool astronomers who have been flying their instruments in U-2s for 20 years that they're doing it all wrong... (Oh no! Now they're doing the same thing in an SR-71! Stop them before it's too late!) Those instruments are handbuilt at no small expense. 20kHz power is a Boondoggle. A gold-plated, aerospace- contractor's-wetdream, engineering-porkbarrel boondoggle. Yeah right, NASA should just stick with old and tried concepts, tie swans to balloons, or use large cannon and capsules lit with gas lamps. And people wonder why NASA has become afraid to take risks and run experimental missions... | Steinn Sigurdsson |I saw two shooting stars last night | | Lick Observatory |I wished on them but they were only satellites | | steinly@lick.ucsc.edu |Is it wrong to wish on space hardware? | | "standard disclaimer" |I wish, I wish, I wish you'd care - B.B. 1983 | ------------------------------ Date: 19 Mar 93 19:55:55 GMT From: Callec Dradja Subject: will dust cool Venus? Newsgroups: sci.space In my original article, I talked about several ideas regarding the terraforming of Venus. I saw some responses to the problem of the dense Venusian atmosphere but no one responded to my proposal of using dust to cool Venus. Will this proposal of putting dust in orbit around Venus in order to cool the planet work? I am afraid that over time, the dust will heat up and begin radiating infrared light which may slightly help warm Venus. I don't think, however, that this effect would be significant. Should I assume that because no one responded to the dust proposal, that everyone thinks that it will work? Gregson Vaux ******************************************************************** * If all we do is live and die, * Gregson Vaux * * then tell me about the birds that fly. * Penn State University * * If all we did was die and live, * Semitics & English * * would springtime be there to forgive? * GRV101@psuvm.psu.edu * ******************************************************************** ------------------------------ End of Space Digest Volume 16 : Issue 342 ------------------------------