Date: Thu, 6 Aug 92 05:04:44 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #077 To: Space Digest Readers Precedence: bulk Space Digest Thu, 6 Aug 92 Volume 15 : Issue 077 Today's Topics: Calendar and Zodiak Comm. Space Act? FRED? Whas' dat? Fwd: Origin of Life article Giotto - First Results from Comet Encounter Magellan Update - 08/05/92 Meteor Soaks Datona FL Meteor Strikes NASA Tools Origin of Life article Phobos & Deimos Uncertainty (2 msgs) Red-blooded ET's : ) Soyuz as ACRV Star Trek (anti-)realism Two-Line Orbital Element Set: Space Shuttle What is the ASRM?? (2 msgs) Whats wrong with this CIRCUIT (was: Tethered Satellites) 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: 5 Aug 92 20:39:28 GMT From: Steve Willner Subject: Calendar and Zodiak Newsgroups: sci.space I think the article below was supposed to be a joke, but it didn't have smileys, and the author has not confirmed that it was. Maybe the joke is on me for following up. In article <1992Jul28.135614.26639@ke4zv.uucp>, gary@ke4zv.uucp (Gary Coffman) writes: > There wasn't a March 2000 years ago. Does "Beware the Ides of March." ring any bells? > The calender we use is a modern invention of the 17th century. Sixteenth (adopted 1582). Adopted at varying times but much later in non-Catholic countries. Also, it seems extreme to call the Gregorian calendar an "invention" when it is such a minor variation on the Julian calendar. > When the Gregorian calendar was rationalized, we lost a week, and > renters rejoiced and landlords cried. It was the landlords who rejoiced, as others have pointed out. And the adjustment was 10 days, not a week. > Precession is not > figured into the calendar. Unless someone rationalizes the calendar again, > the seasons will precess across the months. The Gregorian calendar (365.2425 days per year) is an approximation to the _tropical_ (365.2422 day), not _sidereal_ (365.2564 day) year. The calendar will need a one-day adjustment in roughly 3000 years to stay synchronized with the seasons. Synchronizing to the sidereal year would require an adjustment every 72 years. The Julian calendar (365.25 days per year) was between the sidereal and tropical years but actually a bit closer to the former. The one-time adjustment was meant to make up for the accumulated error from the tropical year. I calculate that the correction brought the seasons back to their dates in AD 300. > The Chinese calendar, and the > Jewish calendar now have the new year occurring on dates other than Jan 1. > That's because both calendars are old enough to have precessed a bit. These are lunar, not solar, calendars and have nothing whatever to do with the Gregorian. In any case, the Jewish new year never started on Jan. 1. (I don't know about the Chinese, Mohammedan, or Indian calendars, but if they ever started on Jan. 1, I would suspect coincidence rather than a common reason for the starting date.) This is well away from sci.space; followups directed to sci.astro. -- Steve Willner Phone 617-495-7123 Bitnet: willner@cfa Cambridge, MA 02138 USA Internet: willner@cfa.harvard.edu member, League for Programming Freedom; contact league@prep.ai.mit.edu ------------------------------ Date: Wed, 5 Aug 1992 18:28:08 -0400 From: David O Hunt Subject: Comm. Space Act? Newsgroups: sci.space What _is_ the commercial space act? Could someone please post some information? David dh4j@cmu.edu ------------------------------ Date: Wed, 05 Aug 92 20:14:16 EDT From: Tom <18084TM@msu.edu> Subject: FRED? Whas' dat? >->What program does "fred" refer to? I've seen it mentioned quite >->a bit but have never come across what it actually is... >-It's a cynical nickname for Space Station Freedom, coined when the thing >-shrunk yet again a couple of years ago. >Actually, somebody on sci.space suggested "Fred" even before Reagan announced >the name "Freedom". I think it may have been Nick, though I'm not sure, that suggested shortening the name even further, to FED, since it's seems little more (to the cynical) than a combination pork/prestige project. -Tommy Mac . " + .------------------------ + * + | Tom McWilliams; scrub , . " + | astronomy undergrad, at * +;. . ' There is | Michigan State University ' . " no Gosh! | 18084tm@ibm.cl.msu.edu ' , * | (517) 355-2178 ; + ' * '----------------------- ------------------------------ Date: Wed, 5 Aug 1992 18:25:42 -0400 From: David O Hunt Subject: Fwd: Origin of Life article Newsgroups: talk.origins,sci.skeptic,sci.space > Why is it so difficult for people who call themselves > scientists to explore the possibility that God created the > earth and all the creatures on it? There is every bit as much > scientific "proof" for the "theory" of creation as there is for > the "theory" of evolution. Why is everyone so set against > acknowledging a valid alternative hypothesis? Is there some > prejudice against is? > Steve Troxel > stroxel@cvgs.schools.Virginia.EDU 1) This is not the place for this article. Try alt.atheist, or talk.origins. 2) What proof of creation? How is it valid? And, if somehow it were valid, why not the buddhist creation, the hindu, the shinto, etc? Why are those any less valid? So...let's teach them ALL!!! Or does this concept bother you? And if so, why? Are you afraid of some competition, not from science, but from other religions? There are myriads of evidence for evolution - fossils, lake-bed sediment that are modulated by astronomical cycles, genetic relations, etc etc etc. WHERE IS THE EVIDENCE _FOR_ CREATIION? The "evidence" given is that of "Well, we've found a possible problem with evolution, so our theory must be the only alternative". Sheesh. Take a course in logic! As to the few problems that arise in the evolutionary support...suppose I give you a coin. You flip it 1,000,000 times, and 999,999 times it comes up heads, once tails. Are you _seriously_ going to tell me that the odds of the next one being tails are favorable? Definite? Because that's what you're claiming with the _overwhelming_ evidence for evolution. "Oh! Oh! We've found a small inconsistency! Must mean that the whole theory is wrong!" Get a life. Religion has a role for some, but any role of religion is suspect in the affairs of science. Can someone else please forward this person some information to read, because I personally am sick and tired of dealing with god sticking his nose into things that he has no affairs in. David Hunt - Graduate Slave | My mind is my own. | Towards both a Mechanical Engineering | So are my ideas & opinions. | Palestinian and Carnegie Mellon University | <<>> | Jewish homeland! ============================================================================ Email: dh4j@cmu.edu Working towards my "Piled Higher and Deeper" Democracy is based on the theory that the people know what they want...and they deserve to get it - GOOD AND HARD! ------------------------------ Date: Thu, 6 Aug 1992 05:18:01 GMT From: Ron Baalke Subject: Giotto - First Results from Comet Encounter Newsgroups: sci.space,sci.astro ESA News Release The Giotto Extended Mission First Results from the Encounter with Comet Grigg-Skjellerup On 10 July 1992, at 15h30 UTC, the Giotto spacecraft passed within approximately 200 km of the nucleus of comet Grigg-Skjellerup. The payload had been switched-on in the evening of 9 July - then the uplink was removed to provide the maximum onboard power margin for a safe operation fo the payload. Eight out of the original complement of eleven experiments were operated and provided a surprising wealth of exciting data: Magnetometer, Johnstone Plasma Analyser, Energetic Particle Analyser, Optical Probe Experiment, Reme Plasma Analyser, Dust Impact Detection System, Ions Mass Spectrometer and Giotto Radioscience Experiment. Already at about 600,000 km from the nucleus, i.e. 12 hours before the closest approach, the Johnstone Plasma Analyser (JPA) detected the first presence of cometary ions. At a distance of 18-15,000 km both JPA and the Reme Plasma Analyser (RPA) reported what looked like a bow shock or a bow wave, much more distinct than had been predicted for such a weak comet. The Magnetometer measurements carried out during the inbound trajectory could not confirm this finding, but reported exciting wave phenomena not seen in a natural plasma before. However, on the outbound trajectory the Magnetometer saw clear indications of a shock. The Optical Probe Experiment got the first indication of entering the dust coma at around 20,000 km and from their data could derive the first estimate for the encounter distance of approximately 200 km. Together with Magnetometer data there is good evidence that Giotto passed the nucleus on the "dark" side, i.e. in the tail forming region. At 15:30:56 the Dust Impact Detectors reported the first impact of a fairly large particle, followed by two smaller ones. At 15:31:02, shortly after the first impact, the High Gain Antenna appeared to be oscillating slightly around its nominal value. An increase of the spin rate by .003 RPM was also observed while the Solar Aspect Angle readings were fluctuating between 89.26 and 89.45 degrees, pointing out a nutation of about 0.1 degrees. This was also recorded by the Radioscience Experiment and is awaiting further evaluation. The Energetic Particle Experiment saw clear indications of the acceleration regions and surprising differences in the structures between the Halley encounter and Grigg-Skjellerup. Last but not least, the Ion Mass Spectrometer recorded good data, however the data analysis for this instrument is quite cumbersome and complex, on the account fo the low encounter velocity (14 km as compared with 68 km/s' at Halley). A thorough test of the camera on-board Giotto on 7 July 1992 could only confirm that the optical path was very effectively blocked. However, on 12 July a number of tests were performed with the detectors of the Halley Multicolour Camera, which had provided very valuable engineering and calibration data on the long term behaviour of the CCD's in space. All experimenters were - and still are - enthusiastic about the quality of the data returned from the Giotto encounter with Grigg- Skjellerup, which surpassed all expectations. The quality of the results obtained during this mission are outstanding and make it another highlight in the history of Giotto and in the history fo the ESA scientific programme. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | You can't hide broccoli in /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | a glass of milk - |_____|/ |_|/ |_____|/ | anonymous 7-year old. ------------------------------ Date: Wed, 5 Aug 1992 19:53:51 GMT From: Martin Connors Subject: Magellan Update - 08/05/92 Newsgroups: sci.space In article <1992Aug5.183414.13985@elroy.jpl.nasa.gov> baalke@kelvin.jpl.nasa.gov (Ron Baalke) writes: > Forwarded from: > PUBLIC INFORMATION OFFICE > JET PROPULSION LABORATORY > Two tests were conducted on Magellan's transmitter B last > week at its minimum temperature of 23.4 C (74 F) to see if high > rate data could be received. Both tests showed a continuing > noise spur at various temperatures ^^^^ Please explain! What is a noise spur? How does it differ from 'noise'? Puzzled in Canada ------------------------------ Date: Wed, 5 Aug 1992 21:23:00 GMT From: Rusty Whitman Subject: Meteor Soaks Datona FL Newsgroups: sci.space In article <1992Aug5.184453.26692@uwm.edu>, gwc@csd4.csd.uwm.edu writes... >From article <1502@tnc.UUCP>, by m0102@tnc.UUCP (FRANK NEY): >> >> -----I quote----- >> A giant wave that drenched Datona FL and caused a lot of damage >> in July turns out to have probably been caused by a 1 meter >> meteor! >> >IS there any source on this meteor event other than a TV news report? > I heard this was caused by an underwater landslide (Washington Post I think). This sounds much more plausible than a meteor strike. If a 1 meter meteor had hit the Atlantic just off Datona Beach there would have been some atmospheric effects along with the wave. Also, I would hope that some Defense radar would have picked it up. One meter objects falling from space are things they look for. Of course, most of the radars look north and west. -------------------------------------------------------------------------- "[W]e think it the height of reckless and extreme folly to address 'violent and vile profanity' to a Butte miner AND a Marine, while such remarks to the miner OR the Marine require only courage." 37 Mich.L.Rev. 874,887 (1939) whitman@istp1.gsfc.nasa.gov (128.183.92.59) -------------------------------------------------------------------------- ------------------------------ Date: Wed, 05 Aug 92 20:17:31 EDT From: Tom <18084TM@msu.edu> Subject: Meteor Strikes >If we lived in afuture time, this scenario would need neither forethought >nor complex long-distance monitoring or planning. >Think of swatting a piece of meat covered in flies; they rise up >before the blow lands. So, we all jump into our personal space vehicles >and tool about for a day or two until the dust has settled. 1) Assuming a time when we have personal space sleds, we probably would not only have an easy way to detect them (lots of colonies, etc.) but also would have a goodly portion of people not even living on the planet. 2) Now think of a bucket full of fish; They get squashed and evicted when you drop a watermelon into it. In your scenarion above, we'd have to tool around for a year or two, before the (worst of) the dust settled, assuming of course that some nuclear-bomb-armed group did not get the lucky draw. They might just assume that their least favorite nation had attacked, which, or course, merits a retaliatory strike...and now our dust not only cools and pollutes, but irradiates. 3) Back to your flies: Assuming that the hand can get a good 40 or 50 flies (ever seen those things congregate in the summer on old, raw, meat. Me either. Sounds like a disgusting experiment, and I don't care to try it, but you can imagine) we might guess that that's 5% of the current fly population. Do YOU want to be part of that 5%? How about the (extremely large) geographical region where your house, job, family members, or friends might be? Imagine the agricultural effects if Kansas (and most of Nebraska, Iowa, Illinois, etc) got hit. I'd say it's worth a bunch of telescopes, dedicated to looking around. We pay people right now for a lot stupider things (My favorite is the Gov. agency, created in the 50's, that is STILL searching for a suitable place for the FDR monument. I think that the agency itself IS the monument :-) PS- _Lucifer's_Hammer_, by, I think, Niven and Pournelle, gives an interesting, if not wholly accurate (who knows, right?) portrayal of the effects of a comet strike. 'Course, that was a multiple hit... The guy surfing the mile-high tidal wave to his death in Silicon Valley was my favorite part. If you liked _The_Stand_, it's pretty similar, but less religious. -Tommy Mac . " + .------------------------ + * + | Tom McWilliams; scrub , . " + | astronomy undergrad, at * +;. . ' There is | Michigan State University ' . " no Gosh! | 18084tm@ibm.cl.msu.edu ' , * | (517) 355-2178 ; + ' * '----------------------- ------------------------------ Date: Wed, 05 Aug 1992 23:19:06 GMT From: Dave Rickel Subject: NASA Tools Newsgroups: sci.space In article <13990@mindlink.bc.ca>, Bruce_Dunn@mindlink.bc.ca (Bruce Dunn) writes: |> > John Roberts writes: |> > ...FPLM, PMKTD, LMAS... |> Crowbar, hammer, and file? Left out baling wire and duct tape (i'll leave it to someone with more imagination to generate the acronyms). david rickel drickel@sjc.mentorg.com ------------------------------ Date: Wed, 5 Aug 1992 22:10:57 GMT From: Greg Moore Subject: Origin of Life article Newsgroups: sci.space In article <1992Aug05.163028.91421@cs.cmu.edu> stroxel@cvgs.schools.Virginia.EDU (Steve Troxel) writes: >Why is it so difficult for people who call themselves >scientists to explore the possibility that God created the >earth and all the creatures on it? There is every bit as much >scientific "proof" for the "theory" of creation as there is for >the "theory" of evolution. Why is everyone so set against >acknowledging a valid alternative hypothesis? Is there some >prejudice against is? > I have two prejudices against your idea. 1) I have NOT seen as much scientific proof for creationism as I have for evolution. I've seen a lot of handwaving. 2) Second, much of the Creationist thoery fails in one major way: Prediction. Any good theory can explain a phenomonon, and I will admit, Creationists can explain a lot. But further, the theory has to be able to predict phenomona. Given a small initial population and conditions, any good evolutionist can describe what will happen. If I introduce a new condition, I can predict what effect it may have on the environment. Creationism fails to do this. The reality may be that God did create everything in 4004BC, but if we want to explain how things occured, and be able to make scientific predictions, we need to develop a SCIENTIFIC theory, not a religous theory. I have no problem with people believing in God creating things, I do have a problem with people claiming that what they present is a scientific hypothesis when it clearly is not. >Steve Troxel >stroxel@cvgs.schools.Virginia.EDU > >**Save the baby humans.** -- <-------------------------------------------------------------------------> Greg d. Moore | Strider@acm.rpi.edu Green Mountain Software | "All that is gold does not glitter." Carpe Diem | ------------------------------ Date: 5 Aug 92 21:55:34 GMT From: "Constantinos A. Caroutas" Subject: Phobos & Deimos Uncertainty Newsgroups: sci.astro,sci.space In article <1992Jul31.170146.17987@jpl-devvax.jpl.nasa.gov>, frisbee@jpl-devvax.jpl.nasa.gov (Tyler Brown) writes: >I posted the message below in sci.astro last week. The results are amusing... > >>>I know that the moon Phobos means "fear" and was a consort of the God >>>of war (Mars/Ares), but I forget what "Deimos" means. Could someone >>>remind me? >>> frisbee@devvax.jpl.nasa.gov >> >>I received several replies, some of which are appended below. >> >>The current vote total is: >> >> Terror 10 >> Panic 6 >> Hate 1 >> Fear 1 (Said that Phobos and Deimos meant fear!) >> ^^^ Hmmm... I can't say that I remember Greek mythology well, but I believe that Phobos and Deimos were sons of the god of war Aris (Mars). "Phobos" means "fear" in modern Greek, while in ancient Greek it also carries the connotation of "respect". "Deimos" is not used in modern Greek. This supports that argument that it also meant "fear". The words for "terror", "panic", and "hate" in Greek are "tromos", "panikos", and "misos" respectively. -- Constantinos A. Caroutas ------------------------------ Date: 5 Aug 92 22:07:58 GMT From: "Constantinos A. Caroutas" Subject: Phobos & Deimos Uncertainty Newsgroups: sci.astro,sci.space In article <92215.110212SCMCC@wvnvm.wvnet.edu>, SCMCC@wvnvm.wvnet.edu (Stephen McCluskey) writes: > > Mythologically, it makes sense that panic is an offspring of >the god of war, especially if you're a Greek infantryman fighting face to Panicos was nobody's son. An ancient Greek messenger told a body of Greek soldiers perparing for battle that he had met god Pan (a minor forest deity) and the god promised him that they would win. They did and the word "panicos" was created to describe the enemy retreat and to honor Pan. -- Constantinos A. Caroutas ------------------------------ Date: 5 Aug 92 19:14:37 GMT From: Paul Dietz Subject: Red-blooded ET's : ) Newsgroups: sci.space In article <1992Aug4.004223.28647@ke4zv.uucp>, gary@ke4zv.uucp (Gary Coffman) writes: |> In article <0eS=5TC00WB6QiD3xK@andrew.cmu.edu> dh4j+@andrew.cmu.edu (David O Hunt) writes: |> >I'll buy the iron argument about magnetic fields, though I think that |> >some other light metal might work...I'm admittedly ignorant about geomagnetics, |> >but isn't it the currents in the core rather than the composition of |> >the core? |> The iron serves to concentrate the field, same as any electromagnet. There |> are other ferromagnetic materials, but they are based on *rare* earth |> elements. Being rare they are unlikely candidates Good grief. Iron is only ferromagnetic at fairly low temperature, below "red hot". It is certainly *not* ferromagnetic when molten, or at the temperature of the Earth's core. Look up the definition of "Curie Point" sometime. The Earth has a magnetic field because it has a core made of a liquid conductor that is undergoing convection. This causes the conductor to move across a magnetic field, which generates a current, which sustains the field. No ferromagnetism involved. Similarly, Jupiter, which has a large core made of liquid metallic hydrogen, has a large magnetic field. The iron content of Jupiter is not very high. The Sun also has a magnetic field, as do many stars. They have little iron (all of it vaporized). The interaction of convection and magnetic fields on these bodies causes all sorts of interesting effects. Paul F. Dietz dietz@cs.rochester.edu ------------------------------ Date: Wed, 05 Aug 92 20:50:23 GMT From: Doug Mohney Subject: Soyuz as ACRV Newsgroups: sci.space In article <1992Aug5.195538.18528@iti.org>, aws@iti.org (Allen W. Sherzer) writes: >In article <1992Aug05.184230.6910@eng.umd.edu> sysmgr@king.eng.umd.edu writes: > >>>Since Soyuz weighs a good deal less than Shuttle it should burn far less >>>fuel. Polution should therefore be lower. > >>Oh. You left out resupply flights. Hm. You'd better go back to the drawing >>board and add those up. > >OK. Since Soyuz and the resuply modules weigh less than the equivalent >Shuttle flights, polution should be lower. I'll hold my nose until someone can put up real numbers. However, if you claim brighter teeth and fresher breath next, I'm going to puke. >Polution is furthur reduced since logistic modules are teathered down >which means both fewer burns for logistics AND fewer burns for Freedom >stationkeeping. This also saves additional $$ since less fuel is needed. So did you add in the money for engineering and tether development? Nyet. Support U.N. military force against Serbia -- > SYSMGR@CADLAB.ENG.UMD.EDU < -- ------------------------------ Date: Wed, 05 Aug 92 20:08:07 EDT From: Tom <18084TM@msu.edu> Subject: Star Trek (anti-)realism >>> AND the way the shuttles bank and turn as if they're >>>airplanes. >>They bank and turn because, if they didn't, you'd bitch that they didn't. >True, but also because pilots/passengers would still feel G-forces in >turns, and it's more natural to have these just going up-and-down as >opposed to side-to-side. Or do the shuttles have the same >high-quality fake gravity machines as the ships? Naw, I got to ride in one at an amusement park, and we were thrown all over the place. We saw a cool film of car chases and roller-coasters, tho. :-) -Tommy Mac . " + .------------------------ + * + | Tom McWilliams; scrub , . " + | astronomy undergrad, at * +;. . ' There is | Michigan State University ' . " no Gosh! | 18084tm@ibm.cl.msu.edu ' , * | (517) 355-2178 ; + ' * '----------------------- ------------------------------ Date: Wed, 5 Aug 1992 21:17:59 GMT From: TS Kelso Subject: Two-Line Orbital Element Set: Space Shuttle Newsgroups: sci.space The most current orbital elements from the NORAD two-line element sets are carried on the Celestial BBS, (513) 427-0674, and are updated daily (when possible). Documentation and tracking software are also available on this system. As a service to the satellite user community, the most current elements for the current shuttle mission are provided below. The Celestial BBS may be accessed 24 hours/day at 300, 1200, 2400, 4800, or 9600 bps using 8 data bits, 1 stop bit, no parity. Element sets (also updated daily), shuttle elements, and some documentation and software are also available via anonymous ftp from archive.afit.af.mil (129.92.1.66) in the directory pub/space. STS 46 1 22064U 92 49 A 92218.12277754 .00088411 00000-0 25599-3 0 159 2 22064 28.4801 317.9864 0004242 309.1517 167.8794 15.91453621 712 EURECA 1 22065U 92 49 B 92218.02794578 -.00023063 00000-0 -55089-3 0 136 2 22065 28.4571 319.5763 0024073 125.3490 235.2134 15.40522860 102 -- Dr TS Kelso Assistant Professor of Space Operations tkelso@afit.af.mil Air Force Institute of Technology ------------------------------ Date: 5 Aug 92 20:16:24 GMT From: "James B. Pettengill" Subject: What is the ASRM?? Newsgroups: sci.space,sci.space.shuttle Just a correction to my previous post: According to the Assembly and Maintenance Implementation Definition Document (AMIDD) dated 9/15/91: Mission Build Payload (lb) Capacity(lb) (220nm) ------------- ------------ -------------------- MB1 38492 37300 MB2 37076 36300 MB3 36653 36300 MB4 37130 36300 MB5 44415 36300 The constraints on the orbiter are as follows: 1. Light orbiter configured for a crew of five (OV-103,104,105) 2. Seven day mission 3. Forward RCS full 4. Two EMU's 5. Four cryo sets installed 6. 220 nm orbit, inclination 28.45 degrees 7. SSME set at 104% during max throttle 8. RMS installed Orbiter payload capacity can be increased with the following trade offs: 1. Decrease altitude +100 lb/nm 2. Delete RMS +1200 lb 3. Delete rendezvous prop +1000 lb 4. Leave 1 astronaut home +500 lb 5. Add 4th cryo-tank set +785 lb ------------------------------ Date: 5 Aug 92 10:50:43 GMT From: Armando Fortuna Subject: What is the ASRM?? Newsgroups: sci.space,sci.space.shuttle >In article <1992Aug4.140921.19282@aio.jsc.nasa.gov> pettengi@ial1.jsc.nasa.gov (James B. Pettengill) writes: >>the asrm program is dead for now but not for long. it should be resurrected >>latter this year or next. >Don't count on it. >>fred can't get off the ground without asrm. >Unless they use Energia. > Allen >-- >+---------------------------------------------------------------------------+ >| Allen W. Sherzer | "If they can put a man on the Moon, why can't they | >| aws@iti.org | put a man on the Moon?" | >+----------------------262 DAYS TO FIRST FLIGHT OF DCX----------------------+ Or unless they use a Saturn V rocket. Rumors say that NASA is thinking about "resurrect" the Saturn V to launch fred in fewer flights than it would take by using the Shuttle. Of course, rebuilding the launch pads for the Saturn, and getting the original contractors to build the parts, would not be easier, and one may say cost-effective. Armando ------------------------------ Date: 5 Aug 1992 16:17:11 -0700 From: Steven Robiner Subject: Whats wrong with this CIRCUIT (was: Tethered Satellites) Newsgroups: sci.physics,sci.space In article <77201@ut-emx.uucp> you write: >I'm cross-posting to sci.space. Scott said that they were having a >similar discussion. I haven't been keeping track there. I hope this >is a help and not a hindrance there. > >In article , srobiner@pollux.usc.edu >(Steven Robiner) writes: >|> >|>Excuse me, but isn't something missing from this "Tethered Satellite" >|>experiment? The shuttle is at one end, and the satellite is at the >|>other, right? But that's an open circuit, so where's the load >|>joining the ends of this 'generator.'? >|> [... stuff deleted ] >of electrons, it will shed them when its potential compared to the >local plasma is higher than the work function for the shuttle surfaces. >So now you have the "infused" electrons into the flux tube that contains >the shuttle. Eventually normal plasma-plasma and plasma-neutral interactions >will allow the electron to move back to its original flux tube. This however >may take some time. So the circuit is really completed in the same sense >that grounded circuits are completed, except here we don't have a good ground But in space, the plasma is not a great conductor, and in fact, moving electrons should be repelled from moving against the magnetic field in a direction opposite from the induced current in the tether, right. I mean, just because the electrons aren't in a wire shouldn't mean that they aren't affected So how will the current manage to travel back up to the satellite? (btw, I guess the point is moot, since the tether is stuck at the moment, but theoretical, what really would happen? ) =steve= ------------------------------ End of Space Digest Volume 15 : Issue 077 ------------------------------