Date: Thu, 19 Nov 92 05:02:37 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #436 To: Space Digest Readers Precedence: bulk Space Digest Thu, 19 Nov 92 Volume 15 : Issue 436 Today's Topics: Breasts in zero-g FREE-ENERGY TECHNOLOGY For Spacecraft Lunar "colony" reality check Lunar "colony" reality check, part 2 (2 msgs) Mars Simulation in Antarctica Minority Kids into Techies (was Re: Free Middle/High School Broadcasts) (2 msgs) ROTATION OF THE MOON (3 msgs) Saturn V for Freedom deployment Shuttle computers Shuttle replacement (5 msgs) Space suit research? What kind of computers are in the shuttle? 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: 18 Nov 1992 17:50:02 GMT From: Claudio Egalon Subject: Breasts in zero-g Newsgroups: sci.space Hmm... That is an interesting point. Sometime ago I read somewhere (I guess it was in the OMNI Space Almanac, I am not sure) that whenever a woman go to space in zero g, the breast keep on floating, in the upwright position. Interesting enough, (still according to the same reference), the same thing happens to the penis of the male astronauts. This is what I call the OverSEX Effect of space-flight, after the Overview Effect concept developed by a guy from Princeton ( I guess that his name is Frank White). No insult was intended, of course. ------------------------------ Date: Wed, 18 Nov 1992 14:52:48 GMT From: Brad Whitehurst Subject: FREE-ENERGY TECHNOLOGY For Spacecraft Newsgroups: sci.space In article <1992Nov17.164440.2394@cnsvax.uwec.edu> mcelwre@cnsvax.uwec.edu writes: > The technology described in the article copied below could be used to >power spacecraft, space colonies, etc.: > > > FREE-ENERGY TECHNOLOGY > by Robert E. McElwaine, Physicist ... > energy" ("2nd law of thermodynamics"). The physicists do not > know how to do certain things, so they ARROGANTLY declare > that those things cannot be done. Such PRINCIPLES OF > IMPOTENCE are COMMON in orthodox modern "science" and help to > cover up INCONSISTENCIES and CONTRADICTIONS in orthodox > modern theories. > > Free Energy Inventions are devices which can tap a > seemingly UNLIMITED supply of energy from the universe, with- > OUT burning any kind of fuel, making them the PERFECT > SOLUTION to the world-wide energy crisis and its associated > pollution, degradation, and depletion of the environment. > ... I think we just found the REAL "Mr. Ozone"! Is there anyone at U. of W. Eau Claire who can verify if this is a real person? Does he do anything but post these articles? -- Brad Whitehurst | Aerospace Research Lab rbw3q@Virginia.EDU | We like it hot...and fast. ------------------------------ Date: Wed, 18 Nov 1992 03:27:59 GMT From: "Carlos G. Niederstrasser" Subject: Lunar "colony" reality check Newsgroups: sci.space > > >> It would take decades > >>of concentrated work to build a Lunar array after permanent manned presence > >>is established on the Moon, if the array is to be constructed from native > >>materials. Meanwhile while we argue about possible paths to take, we forget to do even the most basic research to prove anyside of the argument. As I see it all this bickering is useless unless we have some real data about water at the poles, more general composition or regolith etc... Why argue when we have yet to fully understand what we are arguing about. And then they are the Japanase who quietly spend a little amount on money on research that they know will not pan out for years(decades) if at all. Then at the end of that period if it works they come right back and sell it to us. (Can you say LCDs ?) What is wrong with some basic research to really find out what we need. Having any reality checks either way is pointless. Oh, one last note... Saying any thing will take decades assumes a relatively constant technological base. Say you predict that making a power beaming station on the moon will take 40 years. 40 years is a long time for technology to grow. By the year 20 technology could have changed so much that the next 20 years might be shortend to only 10. The point is once you get above durations of 10 years everything has a very large error to it. IMHO, of course. -- --------------------------------------------------------------------- | Carlos G. Niederstrasser | It is difficult to say what | | Princeton Planetary Society | is impossible; for the dream of | | | yesterday, is the hope of today | | | and the reality of tomorrow | | carlosn@phoenix.princeton.edu |---------------------------------| | space@phoenix.princeton.edu | Ad Astra per Ardua Nostra | --------------------------------------------------------------------- -- --------------------------------------------------------------------- | Carlos G. Niederstrasser | It is difficult to say what | | Princeton Planetary Society | is impossible; for the dream of | | | yesterday, is the hope of today | ------------------------------ Date: Wed, 18 Nov 92 17:09:53 GMT From: amon@elegabalus.cs.qub.ac.uk Subject: Lunar "colony" reality check, part 2 -* Unlike the intrepid Biosphereans, lunar astronauts will - not be able to cheat and come back to civilization to - find good medical care. In a lunabago will be found - little more than a part-time doctor and a first-aid kit. I seem to remember seeing this same line before and my reply is the same. It would be criminal not to insist on someone losing a finger tip in order to keep the experiment pure. We know the answer to the question for colonists, lunar, asteroidal or otherwise... They lose the finger tip and might even die from complications. That is the price you pay and one you had better accept. Anyone who can't do so can stay in their comfy earthworm-city condominium with a nearby LifeFlite to rush them to the Trauma Center. -* Submarines get to surface every month or more, and can come back to - port for food & sex. Nobody has a "submarine colony", even though - it would be far less expensive and more functional than a lunar - "colony". Wrong. John Roberts is correct. I had an office mate who was ex-hunter-killer. Hunter-Killer subs surface now and then. Strategic boats go out, dive deep and stay there for the entire tour unless there is an emergency... Oh,yeah, they have had incidents like burst appendix when they surfaced and had the crewman taken off. Guess they weren't being serious enough about the Cold War :-) Seriously though, it was (is?) a very deadly game. Near collisions at depth were not all that uncommon. The USSR boats couldn't hear the US ones even when they were almost literally on their tail. Sometimes they would suddenly reverse direction... Missile boats don't leave station until the next boat comes out and is sure it has no tails. ------------------------------ Date: Wed, 18 Nov 1992 18:14:23 GMT From: Henry Spencer Subject: Lunar "colony" reality check, part 2 Newsgroups: sci.space In article roberts@cmr.ncsl.nist.gov (John Roberts) writes: >With so many Earth-based processes relying greatly on gravity, can you be >sure that low gravity will be worse than none at all? Experience with >chemical processes in microgravity is very limited - not counting rocket >engines (which I don't think of as a *process* anyway)... And actually, the experience with rockets is moderately instructive... Great pains have to be taken to make sure that fuel flow works right in free fall. Attitude-control engines and minor maneuvering systems typically put a flexible diaphragm between pressurizing gas and fuel, and big main-propulsion engines often simply can't be started without a preliminary shove from a smaller system to settle the fuels to the bottom of the tanks. -- MS-DOS is the OS/360 of the 1980s. | Henry Spencer @ U of Toronto Zoology -Hal W. Hardenbergh (1985)| henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Wed, 18 Nov 1992 16:50:46 GMT From: Pat Subject: Mars Simulation in Antarctica Newsgroups: sci.space In article <17547@mindlink.bc.ca> Bruce_Dunn@mindlink.bc.ca (Bruce Dunn) writes: > At one point I believe that the US was operating a small nuclear >reactor as a source of power and heat in one of their Antarctic bases. Does >anyone know the details - this would be highly relevant to moon and or mars >bases (which of course would have to however have alternate methods of >rejecting heat). THey probably ran SNAP-7 nuclear reactors down in the polar areas. it was there small transportable power rac for science stations, etc.... i seem to recall they were used in the artic as well. look in some historys of nuclear power to be sure. ------------------------------ Date: Wed, 18 Nov 1992 06:43:32 GMT From: Josh 'K' Hopkins Subject: Minority Kids into Techies (was Re: Free Middle/High School Broadcasts) Newsgroups: sci.space higgins@fnalo.fnal.gov (Bill Higgins-- Beam Jockey) writes: >I agree it's a damned shame more females, and members of American minority >groups, don't take up these professions. But sometimes I wonder... >Would it be simpler to ask white males, politely, *not* to become >engineers? Or it might be even more effective to pay them. "You >don't want to be a scientist, kid! Here's some cash." Hmm... Seems to me that any scientist/techie type who is after money is in the wrong field. Be a sports hero or write a romance novel. >This would help make room for the ambitions of young people of other >races, genders, or ethnic heritages to enter techie professions. I don't have the stats to prove it, but I'm sure the ratios of fetal engineers and scientists (those in school) are improving. They still aren't great, but they're far better than they used to be. -- Josh Hopkins jbh55289@uxa.cso.uiuc.edu "Why put off 'til tomorrow what you're never going to do anyway?" ------------------------------ Date: Wed, 18 Nov 92 16:46:11 GMT From: "Bradford B. Behr" Subject: Minority Kids into Techies (was Re: Free Middle/High School Broadcasts) Newsgroups: sci.space In article <1edo1sINNgf0@transfer.stratus.com> det@phlan.sw.stratus.com (David Toland) writes: > >Why would ANYONE want to REDUCE the number of students (white or otherwise) >studying to enter science and technology fields??? We have few enough >students graduating with even minimal competence in mathematics and >the physical sciences. I agree about the "minimal competence" issue -- the percentage of people who are technologically illiterate in our increasingly technological society is sad and is going to (already has) lead to some mighty big problems. But on the other side, there's been a lot of posting recently on sci.research.careers about the glut of physics and csci PhDs, and how jobs for PhDs are hard to come by these days. Unless research and related opportunities are expanded, encouraging students (regardless of race, sex, or species) to go into the sciences could lead to a new population of unemployed. 'Tis a puzzlement. Solutions, anyone? Brad -- ---------------------------------------------------------------------- Bradford B. Behr bbbehr@sunspot.sunspot.noao.edu Sacramento Peak National Solar Observatory, Sunspot NM 88349 ---------------------------------------------------------------------- ------------------------------ Date: 17 Nov 92 20:37:08 GMT From: Trevor German Subject: ROTATION OF THE MOON Newsgroups: sci.space There was a question in rec.puzzles asking how to send a message to the future (real time) say a million years or whatever and I send it this responce. ----------------------------------------------------------------- Re: sending a message to the future. Obviously anything placed on earth is likely to be destroyed by plate techtonics etc so no good burying something. A transmition that takes that long to get back would be hard to receive even if you were expecting it. I have a much better idea. Take a dead satelite. A big one, like say the moon. Then blast its surface with enough nukes to make an easily recognisable pattern that would be only partly erased by comet and meteoride collisions. Then just for good measure, adjust the rotational velocity of the moon so that the message always faces the earth. The message could be something like a big face...................... Came to me in a dream. ------------------------------------------------------------------ I was being a tad facetious (?sp), but it got me thinking about the rotational speed of the moon. I know it has a rotation time that matches the orbit time but I was wondering why this is ? Is the match exact ? I assume it is extremely close since there are no records of it being any different from how we see it now, or at least I don't know of any. What is the governing factor, or is it just a wild coincidence ? ------------------------------------------------------------------- -- >| "Only average people | Trevor J German BSc |< >| never make mistakes." | NCR, Waterloo, Ontario |< >| tjgerman@53iss6.Waterloo.NCR.COM | Canada. |< ------------------------------ Date: Wed, 18 Nov 92 16:38:04 GMT From: "Bradford B. Behr" Subject: ROTATION OF THE MOON Newsgroups: sci.space > I was being a tad facetious (?sp), but it got me thinking about the > rotational speed of the moon. I know it has a rotation time > that matches the orbit time but I was wondering why this is ? > Is the match exact ? I assume it is extremely close since there are > no records of it being any different from how we see it now, or > at least I don't know of any. What is the governing factor, or > is it just a wild coincidence ? Tidal effects (of the earth on the moon, opposite the tides we usually refer to) have "locked" the moon's rotation and revolution periods, such that the same face always faces earthwards (with a little bit of wobble). I'm not clear on all the details of the astrodynamics, but I think it's valid to think of it this way: Just as the moon's gravity makes "bulges" on the earth (manifested in the fluid oceans as high tides), the much more massive earth raises tides in the solid moon, deforming it elliptically. If the moon were rotating (as it once was), the constantly moving deformation would twist and squeeze the moon, heating it, and dissapating the energy. The energy lost as heat would have to come from the moon's rotation, so over billions of years, all the rotational energy (from the earth's point of view) would be lost, and the moon would stop rotating relative to the earth. The same thing is happening, much more slowly, to the earth -- friction with the tides and within the "solid" earth is slowing the rotation rate by something on the order of 1 sec every century. We can actually measure it (the slowdown) nowadays. Love those atomic clocks! Brad -- ---------------------------------------------------------------------- Bradford B. Behr bbbehr@sunspot.sunspot.noao.edu Sacramento Peak National Solar Observatory, Sunspot NM 88349 ---------------------------------------------------------------------- ------------------------------ Date: Wed, 18 Nov 1992 18:35:35 GMT From: Henry Spencer Subject: ROTATION OF THE MOON Newsgroups: sci.space In article <10160@ncrwat.Waterloo.NCR.COM> tjgerman@53iss6.Waterloo.NCR.COM (Trevor German) writes: > ...rotational speed of the moon. I know it has a rotation time > that matches the orbit time but I was wondering why this is ? > Is the match exact ? Yes. The Earth raises tides in the Moon the same way the Moon raises tides in the Earth (there are tides in the Earth's crust and atmosphere as well as in the oceans, although they're less conspicuous). Having tidal bulges constantly moving over the surface takes energy, because there's friction involved in moving that mass around -- be it fluid flow or flexing rock -- and some energy gets lost as heat. That energy has to come from somewhere. Most any small satellite of a larger body will rapidly lose rotational energy to tidal drag, and end up rotating in synchronization with its orbit, so the tidal bulges are "frozen" in and do not move. The Moon is not unique in this; a lot of the planetary moons in the solar system show this locked rotation. It works both ways too. Earth's rotation rate is slowing, very slightly, due to tidal drag from the Moon (and the Sun). It's taking much longer than it took for the Moon, because the Earth is much the more massive of the two. If you want to see tidal effects in action on a large scale, look at Io. Its rotation is locked to Jupiter, but it still has tides because its orbit is slightly elliptical (so the bulges, although fixed in place, rise and fall as the distance to Jupiter varies). Tidal drag would have circularized the orbit long ago, except that Io is locked in a resonance with the other large moons that draws energy from all of them to keep it in that orbit. And so Io *boils* -- it's the tidal friction that keeps those volcanoes erupting furiously on such a small body, which normally would have lost all its internal heat long ago. -- MS-DOS is the OS/360 of the 1980s. | Henry Spencer @ U of Toronto Zoology -Hal W. Hardenbergh (1985)| henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Wed, 18 Nov 1992 03:29:35 GMT From: "Carlos G. Niederstrasser" Subject: Saturn V for Freedom deployment Newsgroups: sci.space In article dfegan@lescsse.jsc.nasa.gov (Doug Egan) writes: > In coley@gn.ecn.purdue.edu (Chris Coley) writes: > > > The Saturn V booster consumed extreme amounts of liquid fuel. > (NOT practical today...) > I am also under the impression that the design documents were > somehow lost... (Maybe to favor the Shuttle program.) > Read the FAQ to find out that the design documents were not lost. Just kept out of the picture and not mentioned until people started wondering about them. -- --------------------------------------------------------------------- | Carlos G. Niederstrasser | It is difficult to say what | | Princeton Planetary Society | is impossible; for the dream of | | | yesterday, is the hope of today | | | and the reality of tomorrow | | carlosn@phoenix.princeton.edu |---------------------------------| | space@phoenix.princeton.edu | Ad Astra per Ardua Nostra | --------------------------------------------------------------------- -- --------------------------------------------------------------------- | Carlos G. Niederstrasser | It is difficult to say what | | Princeton Planetary Society | is impossible; for the dream of | | | yesterday, is the hope of today | ------------------------------ Date: 18 Nov 92 18:51:47 GMT From: Henry Spencer Subject: Shuttle computers Newsgroups: sci.space In article roberts@cmr.ncsl.nist.gov (John Roberts) writes: >Is it at all possible to reprogram the GPCs from the ground, or does it >have to be done from onboard? They are routinely reloaded with different software from onboard storage (tape, I think), but I don't think there is any remote-upload capability. In an emergency, the astronauts can input patches manually -- NASA insisted on this capability, over IBM's objections (the IBM folks say they considered having the patch routine pop up a little flag saying "your warranty is void" when it was used :-)) -- but that's not suitable for routine use. -- MS-DOS is the OS/360 of the 1980s. | Henry Spencer @ U of Toronto Zoology -Hal W. Hardenbergh (1985)| henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Wed, 18 Nov 1992 06:27:29 GMT From: Josh 'K' Hopkins Subject: Shuttle replacement Newsgroups: sci.space.shuttle,sci.space aws@iti.org (Allen W. Sherzer) writes: >In article <69532@cup.portal.com> BrianT@cup.portal.com (Brian Stuart Thorn) writes: >>It seems to me that in 1992, Space Shuttle is offering one of the best >>returns on investment in the space community! >Atlas and Delta are providing profits for the companies which build them. >That means they offer a return on investment. I agree with Allen that ELVs are better than Shuttle for many things, but I'm quite certain that I read that Atlas was actually loosing money for GD and had been for a while. -- Josh Hopkins jbh55289@uxa.cso.uiuc.edu "Why put off 'til tomorrow what you're never going to do anyway?" ------------------------------ Date: Wed, 18 Nov 1992 03:40:10 GMT From: "Carlos G. Niederstrasser" Subject: Shuttle replacement Newsgroups: sci.space Talking about the possible merits of HL-20, DC-Y, NASP, etc is a good thing. Whatever program you support lets make sure is flying before the shuttle stops. In my opinion giving a more or less specific date such as 2005 for the shuttle to stop is a bad mistake, if we don't have realtively certain dates for any replacements. Let us not forget history. Twenty years ago 3 (or more) fully operational Saturn V were left as museum pieces accross the country. As much as I would like to see Columbia at KSC, let's try not to shoot ourselves in the foot again and let go of our heaviest capacity lift vehicle. (notice I said heaviest and not heavy :) -- --------------------------------------------------------------------- | Carlos G. Niederstrasser | It is difficult to say what | | Princeton Planetary Society | is impossible; for the dream of | | | yesterday, is the hope of today | | | and the reality of tomorrow | | carlosn@phoenix.princeton.edu |---------------------------------| | space@phoenix.princeton.edu | Ad Astra per Ardua Nostra | --------------------------------------------------------------------- -- --------------------------------------------------------------------- | Carlos G. Niederstrasser | It is difficult to say what | | Princeton Planetary Society | is impossible; for the dream of | | | yesterday, is the hope of today | ------------------------------ Date: 18 Nov 92 13:34:12 GMT From: "Allen W. Sherzer" Subject: Shuttle replacement Newsgroups: sci.space.shuttle,sci.space In article <1992Nov16.193337.9963@aio.jsc.nasa.gov> devenzia@euler.jsc.nasa.gov (John DeVenezia) writes: >> How can the Shuttle possibly be said to offer ANY (much less the best) return >> on investment? Shuttle has LOST billions. >Well, considering that the Shuttle project also provides/provided profits for the >companies which launch/re-furbish/built it can you tell us what the difference >is? Your saying that since the subcontractors are turning a profit it therefore follows that NASA is making a profit. If you think about that for a moment you will see that it makes no sense. It's like saying that Boeing is making a profit and therefore American Airlines must be profitable as well. Profit is when you collect more in fees/sales than you spend. If you add up all the money collected in fees and subtract out the amount spent you will see that Shuttle has lost billions. >Consider that the Atlas and Delta carry many goverment payloads. Sure. But they charge the government more than their costs. They make a profit and therefore have a return on investment. Shuttle simply doesn't have either. Allen -- +---------------------------------------------------------------------------+ | Allen W. Sherzer | "A great man is one who does nothing but leaves | | aws@iti.org | nothing undone" | +----------------------157 DAYS TO FIRST FLIGHT OF DCX----------------------+ ------------------------------ Date: Wed, 18 Nov 1992 13:43:48 GMT From: "Allen W. Sherzer" Subject: Shuttle replacement Newsgroups: sci.space.shuttle,sci.space In article <69649@cup.portal.com> BrianT@cup.portal.com (Brian Stuart Thorn) writes: >>> Atlas and Delta are providing profits for the companies that make them << >As for Delta, absolutely, positively right. But I fail to see how depositing >two enormously expensive satellites in the Atlantic can be said to be >a profit for General Dynamics and the Atlas. Simple: it costs GD X to launch an Atlas. They charge the customer a sum greater than X to launch their satellite. This results in a profit. Now will GD continue to be profitable if they don't fix the Centaur problems? I doubt it but that's not the same thing. >The Space Shuttle was already more-or-less paid for, so why not use it. Because even paid for is still costs three times as much as the alternatives. >I was trying to say (got sidetracked, I must admit) that the U.S. should >have put its money into a new unmanned booster system, not tired old >designs like Titan and Atlas. Those 'tired old designs' will put the same payloads in orbit for a third the cost. The US shouldn't be putting it's money into the design of ANY expendable launcher. We have done that for too long and it's hasn't reduced launch costs by a dime. Allen -- +---------------------------------------------------------------------------+ | Allen W. Sherzer | "A great man is one who does nothing but leaves | | aws@iti.org | nothing undone" | +----------------------157 DAYS TO FIRST FLIGHT OF DCX----------------------+ ------------------------------ Date: 18 Nov 92 18:48:41 GMT From: Henry Spencer Subject: Shuttle replacement Newsgroups: sci.space.shuttle,sci.space In article <1992Nov18.134348.16504@iti.org> aws@iti.org (Allen W. Sherzer) writes: >The US shouldn't be putting it's money into the design of ANY expendable >launcher. We have done that for too long and it's hasn't reduced launch >costs by a dime. Actually, this isn't a very sound argument. The US has been putting big bucks into small improvements to the performance and reliability of 50s- vintage expendable launchers. It *hasn't* made any serious effort to build a cheaper one (which cannot be done without changing the way the launchers are built and operated -- it's not the fuels and metals that cost all that money, but the way they're used). All that money has been going into squeezing one more ounce out of existing designs, and any sane engineer will predict a lousy cost/benefit ratio for that approach. No conclusion can be drawn about the possibility of cheaper expendables; it has not been tried. Even the projects that have officially included "lower costs" in their objectives have always had higher-priority objectives (typically, maximum payload and maximum reliability) that pushed them toward higher, not lower, costs. Certainly, even after you get past complications like different accounting systems, there is no possible doubt that launchers like Soyuz and Long March really are substantially cheaper to run than Atlas or Delta. It *can* be done. -- MS-DOS is the OS/360 of the 1980s. | Henry Spencer @ U of Toronto Zoology -Hal W. Hardenbergh (1985)| henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 18 Nov 92 07:17:10 EST From: Chris Jones Subject: Space suit research? Newsgroups: sci.space In article , roberts@cmr (John Roberts) writes: >I believe the astronauts normally moved between the Command Module and the >Lunar Module via a pressurized docking adapter. However, while two of the >astronauts were on the moon, a camera mounted on the Service Module was >busy taking beautiful stereo aerial photos of the lunar surface. (Aerial?) This was done on the later flights, which spent more time in the vicinity of the moon. I recall this started with Apollo 15, but I don't have a reference handy to confirm that. > When the >astronauts came back from the moon, one of them had to do an EVA to >retrieve the film. This is depicted in the NASA Select video of Apollo 16 >(a great video, if you ever have a chance to see it). > >I'm not sure whether this was done before or after unsealing the Lunar Module - >Command Module adapter - I would guess before, so the Command Module would >not have to be depressurized. As I recall, the EVA was done on the return trip to earth, after the LM upper stage had been discarded. The CM, naturally, was depressurized. It was the CM pilot who got to do the EVA (he was owed, after all!). >Question: was the Lunar Module normally pressurized before takeoff? Yes. It was repressurized basically immediately after every EVA so the astronauts could take off their helmets and gloves. > And >after the film EVA, was it pressurized again before unsealing the docking >adapter? See above. -- Chris Jones clj@ksr.com ------------------------------ Date: Tue, 17 Nov 1992 01:52:57 GMT From: moroney@ramblr.enet.dec.com Subject: What kind of computers are in the shuttle? Newsgroups: sci.space In article <18741@ksr.com>, jfw@ksr.com (John F. Woods) writes... >Rad-hard SRAM, 50 bits of ECC for each 32 bits of memory, *and* a background >scrub cycle every two seconds. They didn't buy this at "BACK OF THE TRUCK >PEECEES, LIMITED", nosir! Interesting. Would you happen to know how many errors this memory can detect and correct? -Mike ------------------------------ End of Space Digest Volume 15 : Issue 436 ------------------------------