Date: Thu, 16 Jul 92 05:00:04 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #004 To: Space Digest Readers Precedence: bulk Space Digest Thu, 16 Jul 92 Volume 15 : Issue 004 Today's Topics: Chemical unit operations in space (6 msgs) Coding on Galileo FTL drives (5 msgs) GIOTTO and GRIGG-SKJELLERUP (on TV!) Interplanetary communications relays (2 msgs) Interplanetary Relays N2 in nuclear thermal rocket / Hohmann to Venus Now, where at last ? (Re: apollo 10) (2 msgs) Space Power Welcome to the Space Digest!! Please send your messages to "space@isu.isunet.edu" (on Internet). If you are on Bitnet, you must use a gateway (e.g., "space%isu.isunet.edu@CUNYVM"). Please do **NOT** send (un)subscription requests to that address! Instead, send the message "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: 15 Jul 92 11:48:52 GMT From: M22079@mwvm.mitre.org Subject: Chemical unit operations in space Newsgroups: rec.arts.sf.science,sci.space In article <1992Jul15.065617.27597@ccu1.aukuni.ac.nz> ecmtwhk@ccu1.aukuni.ac.nz (Thomas Koenig) writes: >I've been wondering a bit about how a chemical plant would look >like in space. > ---- typical chemical engineering separation techniques deleted -- I would like to change your frame of reference from polypropylene to biotech and suggest that for the small batches to be done in space the unit ops would be capillary extraction, reverse osmosis, electrophoresis, diffusion based separation. We lose density as a bulk separator, but we also lose 2 dimensiona l constraints on various processes. Charge on particles, convection currents and other forces that are small compared to gravity will become important. Density can still be used but as you noted it will need to be done carefully as the spacecraft is it own frame and disturbance torques will be felt througho ut the spacecraft. I think that it will take many years but once the new situation is thoroughly explored the unit ops will be more varied and possibly for specific types of production cheaper. Karl Pitt (KPITT@MITRE.ORG) PS: These opinions are mine alone and do not reflect the views of MITRE or my Chem E professors (long ago in a galaxy far away). ------------------------------ Date: 15 Jul 92 14:14:00 GMT From: Greg Macrae Subject: Chemical unit operations in space Newsgroups: rec.arts.sf.science,sci.space In article <1992Jul15.065617.27597@ccu1.aukuni.ac.nz>, ecmtwhk@ccu1.aukuni.ac.nz (Thomas Koenig) writes... >I've been wondering a bit about how a chemical plant would look >like in space. > >If you assume microgravity conditions, there are going to be severe >difficulties in separating two phases, which affects just about >everything. Some examples: (examples deleted) There are many benefits to processing in microgravities, but not all processes are suitable. Many processes that require distillation or centrifuging can be conducted with electrophoresis and other techniques. Moving solids becomes easier because conveyer belts are not needed, just set the solids in motion and they keep going along their orbital track. Centrifuges will still function as on Earth, and by processing at accellerations greater than 1 g, less time, space, etc. is needed. Boiling presents some very interesting challenges. Solutions vary with the requirements, bulk boiling can be conducted by vaporizing the entire quatity of liquid and then extracting the gas. Flow boiling can be conducted in a packed bed configuration or, if the heat of vaporization is low enough, you can superheat the liquid and then flash it to a vapor through an orifice. The last shuttle flight demonstrated a very high degree of control over droplet location, and motion using sound waves, and that was the first such experiment ever conducted! Working with fluid is not impossible, it just requires different techniques on orbit. >Conclusions: to build a chemical factory in orbit, build a rotating one >with about 10 m/s^2 of acceleration (but make it big, current distillation >columns are up to 50 m high); if you want to build something like that >on the moon, build a couple of universities there first and let the >people study things there for about a decade. Providing an artificial accelleration environment nullifies one of the biggest benefits of orbital processing. Additionally, you will find that the peculiarities of an accelleration field produced by rotation (apparently curved trajectories, varying accelleration, rotational+orbital interactions, etc.) will not even allow you the benefit of exact translation of many Earth based processes. It will be much more effective to exploit the advantages of microgravity on orbit than to try to reproduce earthly conditions. ------------------------------ Date: Wed, 15 Jul 1992 12:30:00 -0400 From: "Andrew C. Plotkin" Subject: Chemical unit operations in space Newsgroups: sci.space,rec.arts.sf.science In article <1992Jul15.065617.27597@ccu1.aukuni.ac.nz>, ecmtwhk@ccu1.aukuni.ac.nz (Thomas Koenig) writes... >Conclusions: to build a chemical factory in orbit, build a rotating one >with about 10 m/s^2 of acceleration (but make it big, current distillation >columns are up to 50 m high); if you want to build something like that >on the moon, build a couple of universities there first and let the >people study things there for about a decade. A rotating disk-shaped station would have every gravity level you might want, without vibration (or at least no more vibration than any other large inhabited structure.) There's not much room at the center for microgravity work, though. None at all if the rotation is a significant effect. Maybe a dumbell-shaped station, with a rotating disk and a nonrotating disk, connected by an axle. (Connecting chemical pipes across the axle is the fun part.... :-) --Z "And Aholibamah bare Jeush, and Jaalam, and Korah: these were the borogoves..." ------------------------------ Date: Wed, 15 Jul 92 18:57:19 GMT From: Nick Haines Subject: Chemical unit operations in space Newsgroups: sci.space,rec.arts.sf.science One advantage that space has over ground-based systems is that your centrifuge (or all your centrifuges) can be mounted on a platform which is completely independent of the micro-gravity platform. Vibrations won't be a problem. Nick ------------------------------ Date: 15 Jul 92 18:23:01 GMT From: Bill Higgins-- Beam Jockey Subject: Chemical unit operations in space Newsgroups: sci.space In article <15JUL199210142634@mars.lerc.nasa.gov>, spgreg@mars.lerc.nasa.gov (Greg Macrae) writes: > In article <1992Jul15.065617.27597@ccu1.aukuni.ac.nz>, ecmtwhk@ccu1.aukuni.ac.nz (Thomas Koenig) writes... >>I've been wondering a bit about how a chemical plant would look >>like in space. > Centrifuges will still function as on Earth, and by processing at > accellerations greater than 1 g, less time, space, etc. is needed. [...] > It will be much more effective to exploit the advantages > of microgravity on orbit than to try to reproduce earthly conditions. In "Borovsky's Hollow Woman," an SF short story published in *Omni* some years ago, Jeff Duntemann and Nancy Kress suggested that the good old "wheel" space station might be spun to yield accelerations larger than 1 g at its outermost or "lowest" levels, so that some chemical processing could take advantage of higher "gravity." Most people would inhabit the part of the station that was at 1 g or lower, but industry would occupy the high-g levels. Workers there needed powered spacesuits-- that's what the Hollow Woman was. I suspect using a small centrifuge gets you high g's more easily than this elaborate solution. Thomas Koenig was complaining that a spinning station would louse up microgravity. Why not have two stations-- one with microgravity, one in the same orbit which spins? Let the spinner do all the stationkeeping so the floater is not disturbed. Engineer of Hijacked Train: Bill Higgins "Is this a holdup?" Fermi National Accelerator Laboratory Masked Gunman: (Hesitates, looks at partner, Bitnet: HIGGINS@FNAL.BITNET looks at engineer again) SPAN/Hepnet/Physnet: 43011::HIGGINS "It's a science experiment!" Internet: HIGGINS@FNAL.FNAL.GOV ------------------------------ Date: 15 Jul 92 20:02:53 GMT From: Arrowsmith Subject: Chemical unit operations in space Newsgroups: rec.arts.sf.science,sci.space In article <1992Jul15.065617.27597@ccu1.aukuni.ac.nz> ecmtwhk@ccu1.aukuni.ac.nz (Thomas Koenig) writes: >>I've been wondering a bit about how a chemical plant would look >>like in space. >> I'm wondering what *use* this sort of chemical plant would have. You're going to have to ship the raw materials up to orbit, and return the products (there's not likely to be much of a market elsewhere!) -- so why move anything other than stuff either side of the micro-g phase of the process? Even if it's "inconvenient" I imagine it would be both easier and cheaper than trying to overcome the technical problems of putting the whole operation up there.... -- \S "I ride tandem with the random SA121@phx.cam.ac.uk "Things don't turn out the way I plan them sarrowsm@nyx.cs.du.edu "In the humdrum" and elsewhere.... --Peter Gabriel ------------------------------ Date: Wed, 15 Jul 1992 23:19:08 GMT From: Ron Baalke Subject: Coding on Galileo Newsgroups: sci.space In article <18021.2a63ec33@levels.unisa.edu.au>, etssp@levels.unisa.edu.au writes... >In article <1992Jul10.171747.5067@elroy.jpl.nasa.gov> >baalke@kelvin.jpl.nasa.gov (Ron Baalke) writes: >>3. On July 8, as part of the Warming/Cooling Turn No. 6A activities, >>real-time commands were sent to switch from 10 bps coded telemetry to 40 bps > ^^^^^^ ^^^^^^ >>coded telemetry. > >What sort of coding is used in the 10 bit/s and 40 bit/s data rates? Is it the >standard K = 7 rate 1/2 convolutional code? What sort of coding is going to >be used to get 100 bit/s from Jupiter (is it the new K = 15 rate 1/4 >convolutional code concatenated with the standard (255,223) Reed Solomon outer >code?). For all bit rates under 134,400 bps, Galileo uses the K=7, R=1/2 convolutional coding for its coded telemetry. The K=15, R=1/4 convolutional coding is reserved for the 134,400 bit rate, and the DSN is currently being upgraded to support this. You also need the High Gain antenna to be open to use the higher bit rate. The Reed Solomon (255,223) encoding is optional, and was used on the Gaspra images. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | In 1991 there were 16 names /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | listed on the FBI's ten |_____|/ |_|/ |_____|/ | most wanted list. ------------------------------ Date: 15 Jul 92 04:37:20 GMT From: Kent Schumacher Subject: FTL drives Newsgroups: sci.space In article , derek.wee@f820.n680.z3.fido.zeta.org.au (Derek Wee) writes... > >Just out of interest, I'm compiling a list of the FTL drives used in >science fiction stories and computer games. I have already got: > Bob Shaw's "Nightwalk" had a 200 meter ship with a matter transmitter in the tail, and a matter receiver in the nose. I seem to remember they used tachyons to do the matter transmission, so when the ship transmitted itself to it's nose, it went faster than light (for 200 meters). It would be interesting to see how many "transports per second" you would need to achieve a speed significantly FTL. I think Larry Niven talked about sending STL ships with FTL teleportation receivers in an article titled (I think) the "Theory and Practice of Teleportation". I'm not sure but I believe "Stargate" by Stephen Robinette and "Mindbridge" by Joe Haldeman used receiverless FTL transporters. Glen Cook's "The Dragon Never Sleeps" proposed "The Web", which was an artificial construct that allowed ships to travel FTL along it's members. >3) Sub-universe. Used Exclusively in Microprose's `LIghtspeed'. The ship >coccoons itself in a sub-universe. It can move this universe (with itself in > it) through the `real' universe faster than light. Well, no... This has been used in several science fiction stories. The first that comes to mind is Glen Cook's "Passage at Arms", where they called the process "climbing", and the sub-universe "Null", or some such. "Yesterday's Children" by David Gerrold has ton's of fictional info on pocket universes, and his version of "Warp". Gully Foyle, in "The Stars My Destination" by Alfred Bester, psychically teleports himself across space and time. This happens in "Sentinals From Space" by Eric Frank Russel also (well, space anyway, but what's the difference). Does traveling STL and then rotating yourself into the past at your destination count as FTL? I hope you realize this could go on all night (and I'm sure many would say it's gone on far too long already). >||))) If you build it )))))))))))))))))))))))))))))| >||))) They will cancel it - Field of Dweebs. )))))))))))))))))))))))))))))| >||))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))))| >||Dave Jones (dj@ekcolor.ssd.kodak.com) | Eastman Kodak Co. Rochester, NY | -- --- I've spent so much on this computer, I can't afford a signature Kent Schumacher ------------------------------ Date: 15 Jul 92 14:02:13 GMT From: Bob Pendelton Subject: FTL drives Newsgroups: sci.space From article <13JUL199212295133@lims02.lerc.nasa.gov>, by afwendy@lims02.lerc.nasa.gov (WENDY WARTNICK): > What was the method they used in "Dune"? It was not one of the mentioned, > but I cannot remember it offhand. > Wendy I'd describe it as heavy drugs and lots of wishing... Bob P. -- Bob Pendleton | As an engineer I hate to hear: bobp@hal.com | 1) You've earned an "I told you so." Speaking only for myself. | 2) Our customers don't do that. <<< Odin, after the well of Mimir. >>> ------------------------------ Date: Wed, 15 Jul 1992 15:15:44 GMT From: James Davis Nicoll Subject: FTL drives Newsgroups: sci.space [Note followup line] Jack DeWinter over on one of the sf or the gaming groups has a very extensive list of FTL drives, worth asking for. James Nicoll ------------------------------ Date: Wed, 15 Jul 1992 16:23:38 GMT From: Bob Martino Subject: FTL drives Newsgroups: sci.space In DUNE they used drugged-out floating monsterous bloob things to "warp" space with their minds. One of the reasons why I detested that movie. _________________________________________________________________________ | "...for since the creation of the - that Bob Martino guy - | world His invisible attributes, bmartino@magnus.acs.ohio-state.edu | His eternal power and divine | nature, have been clearly seen, God invented science. so there. | being understood through what ^^^^^^^^ | has been made -Romans 1:20 ------------------------------------------------------------------------- "That's the whole problem with science. You've got a bunch of empiricists trying to describe things of unimaginable wonder." -Calvin ------------------------------ Date: 15 Jul 92 16:12:00 GMT From: "Howard Fink,Ed Site,83422,_" Subject: FTL drives Newsgroups: sci.space The Lensmen series used an inertialess drive. Somehow, the ship lost its inertia, and a reaction drive sped the ship to the limit of heating caused by skin friction with the ether. Ships were streamlined and refrigerated to go faster. Howard Fink ------------------------------ Date: 15 Jul 92 02:26:41 GMT From: Keith Harwood Subject: GIOTTO and GRIGG-SKJELLERUP (on TV!) Newsgroups: sci.astro,sci.space There was a piece about the G-S encounter on the TV news the night it happened. They showed the `just before closest approach' photo from the Halley encounter, with glowing craters and gas beams. Presumably the picture has been enhanced. What would one see if one was standing where Giotto had been? I would guess one would see just a dark lump, with the glow too dim for the naked eye, or is there enough material around to reflect sufficient light? Keith Harwood. ------------------------------ Date: Wed, 15 Jul 1992 23:40:25 GMT From: Ron Baalke Subject: Interplanetary communications relays Newsgroups: sci.space In article <9207150211.AA07127@cmr.ncsl.nist.gov>, roberts@CMR.NCSL.NIST.GOV (John Roberts) writes... >That still leaves the possibility of close-up relays. As Nick says, if you >want to send a *lot* of scientific probes to Mars or Jupiter, then having a >relay in orbit around the planet could possibly save the expense of putting >a powerful high-gain system on every one of those probes. The decision on >whether to do it this way depends on the number of probes planned, the >relative cost, and the bandwidth needed. (I believe the Viking landers >used orbital relays, though they could also communicate directly.) There is an option being looked into with the MESUR mission of sending a communications orbiter to Mars. Even though each of the sixteen landers will be able to talk directly to Earth, it will be at a low bit rate and the communications orbiter would significently increase the bandwidth. >*If* the decision had been made to send a relay probe to Jupiter to help >Galileo, what sort of bandwidth might we have reasonably expected? > 134,400 bps. >And what bandwidth can Galileo get over the low gain antenna during an Earth >flyby? 134,400 bps was used to playback the Venus data just prior to the December 1990 Earth flyby, and the same rate will be used for the Gaspra playback for Earth flyby this coming December. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | In 1991 there were 16 names /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | listed on the FBI's ten |_____|/ |_|/ |_____|/ | most wanted list. ------------------------------ Date: Wed, 15 Jul 1992 15:38:27 GMT From: Henry Spencer Subject: Interplanetary communications relays Newsgroups: sci.space In article <9207150211.AA07127@cmr.ncsl.nist.gov> roberts@CMR.NCSL.NIST.GOV (John Roberts) writes: >... Inverse square loss isn't the main problem, otherwise the >relays would have a strong advantage. The problem is that the receivers/ >transmitters on the ground are so much better than anything we can put in >space with current technology, that even with inverse square loss, space >relays can't compete over long distances. So if your scientific probe is at >Saturn, then a relay at the orbit of Jupiter can't communicate with it as >well as a DSN station, despite the much shorter distance... Actually, inverse-square loss and technology limitations tie together. The problem with the Jupiter relay is that it's almost as far away from Saturn as we are! Even if it's halfway to Saturn (which Jupiter isn't), that only gives it a factor-of-4 advantage over Earth-based stations, which is not nearly enough (and probably never will be) to make up for the additional engineering problems. To make deep-space relay stations worthwhile, they've really got to show an improvement of at least a couple of orders of magnitude. The only way to do that is to put them relatively close to the probes they're relaying for. -- There is nothing wrong with making | Henry Spencer @ U of Toronto Zoology mistakes, but... make *new* ones. -D.Sim| henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Wed, 15 Jul 1992 14:00:05 GMT From: Stuart A Kingsley Subject: Interplanetary Relays Newsgroups: sci.space In the future there will be less need for Interplanetary Radio Frequency Relays if the main means of communication becomes laser based. The 21st Century will see photonics provide most long-distance communications. This includes fiber-optics on the ground, GEO to GEO communications, communications with the outer reaches of the solar system, and finally, interstellar communications. Think: Small Is Beautiful Stuart * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * Dr. Stuart A. Kingsley, CEng, * * Consultant, * * MIEE, SMIEEE, * * The Planetary Society, * * Space Studies Institute, * * Columbus Astronomical Society, * * Volunteer, SETI Group, Ohio State. * * * * "Where No Photon Has Gone Before & * * The Impossible Takes A Little Longer" * * __________ * * FIBERDYNE OPTOELECTRONICS / \ * * 545 Northview Drive --- hf >> kT --- * * Columbus, Ohio 43209 \__________/ * * United States * * Tel/Fax: (614) 258-7402 .. .. .. .. .. * * Manual Fax Tone Access Code: 33 . . . . . . . . . . * * Bulletin Board System (BBS): .. .. .. .. * * Modem: (614) 258-1710, * * 300/1200/2400/4800/9600 Baud, MNP, 8N1. * * Internet: skingsle@magnus.acs.ohio-state.edu * * CompuServe: 72376,3545 * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * ------------------------------ Date: 15 Jul 92 11:58:27 GMT From: FRANK NEY Subject: N2 in nuclear thermal rocket / Hohmann to Venus Newsgroups: sci.space > Frank, older editions do have the table. So does the 1991 ed (surprise!). Page 14-28 thru 14-31. Now if I can just figure out what I'm supposed to do with it..... Frank Ney N4ZHG EMT-P LPVa NRA ILA GOA CCRTKBA "M-O-U-S-E" Commandant and Acting President, Northern Virginia Free Militia Send e-mail for an application and more information ---------------------------------------------------------------- I don't care if they get the kind of government they deserve, Why do *I* have to get the kind of government they deserve? -- The Next Challenge - Public Access Unix in Northern Va. - Washington D.C. 703-803-0391 To log in for trial and account info. ------------------------------ Date: 15 Jul 92 17:16:17 GMT From: Shari L Brooks Subject: Now, where at last ? (Re: apollo 10) Newsgroups: sci.space In article <1992Jul15.011906.19423@usenet.ins.cwru.edu> wb8foz@skybridge.scl.cwru.edu (David Lesher) writes: >Others said ># ># And -- Is there a listing (or something like) where those hardware of past ># space endeavors went, which is not on earth or earth orbit ? (Apollo AND ># unmanned probes) > >Well, I think the folks at NORAD in Colorado Springs keep track >of everything up there. But, I doubt they answer many >questions..... Actually, every three months (i think) USSPACECOM publishes an unclassified catalog of all that stuff. I don't get it but I am sure one is kicking around here somewhere, if I find it I will post the appropriate titles, offices, and reference numbers. -- Shari L Brooks | slb%suned1.nswses.navy.mil@nosc.mil NAVSOC code NSOC323D | shari@caspar.nosc.mil NAWS Pt Mugu, CA 93042-5013 | --> All statements/opinions above are mine and mine only, not the US Navy's. ------------------------------ Date: 15 Jul 92 18:56:11 GMT From: Shari L Brooks Subject: Now, where at last ? (Re: apollo 10) Newsgroups: sci.space I wrote: >In article <1992Jul15.011906.19423@usenet.ins.cwru.edu> wb8foz@skybridge.scl.cwru.edu (David Lesher) writes: >>Others said >># >># And -- Is there a listing (or something like) where those hardware of past >># space endeavors went, which is not on earth or earth orbit ? (Apollo AND >># unmanned probes) [...to borrow a phrase...MUNCH! :) ] >Actually, every three months (i think) USSPACECOM publishes an unclassified >catalog of all that stuff. I don't get it but I am sure one is kicking around >here somewhere, if I find it I will post the appropriate titles, offices, and >reference numbers. Well, I looked around and we don't have one, although I am still certain it exists. What we *do* have is the annually published "Satellite Situation Summary" which NAVSPASUR puts out For Official Use Only. This document is updated monthly, I believe. For what it's worth, it does mention the Apollo 10 LM as being out there, but states that NAVSPASUR never had an element set for it. -- Shari L Brooks | slb%suned1.nswses.navy.mil@nosc.mil NAVSOC code NSOC323D | shari@caspar.nosc.mil NAWS Pt Mugu, CA 93042-5013 | --> All statements/opinions above are mine and mine only, not the US Navy's. ------------------------------ Date: Wed, 15 Jul 1992 16:21:16 GMT From: Bob Martino Subject: Space Power Newsgroups: sci.space In article <19949@sbsvax.cs.uni-sb.de> dietz@mpi-sb.mpg.de writes: >In article 7394@techbook.com, szabo@techbook.com (Nick Szabo) writes: > >> This is more properly called Dietz's scheme, though I jabber about it >> alot and have some refinements. I might argue with your heiarchy of >> difficulty. Putting a conducting tether (a la TSS-1) on Metis is >> pretty easy, given a magsail or electromag brake for getting low enough >> in Jupiter orbit. Equipment mass per kilowatt is orders of magnitude less >> than SPS. The hard part is getting the power back to Earth. Somebody >> suggested using an IR laser for beaming from the Moon; anybody ready for >> X-ray power transmission? :-) > It occurs to me that by the time we have developed sufficient technological know-how to construct something like this, we will probably not need such a thing. Just mt $0.02 _________________________________________________________________________ | "...for since the creation of the - that Bob Martino guy - | world His invisible attributes, bmartino@magnus.acs.ohio-state.edu | His eternal power and divine | nature, have been clearly seen, God invented science. so there. | being understood through what ^^^^^^^^ | has been made -Romans 1:20 ------------------------------------------------------------------------- "That's the whole problem with science. You've got a bunch of empiricists trying to describe things of unimaginable wonder." -Calvin ------------------------------ End of Space Digest Volume 15 : Issue 004 ------------------------------