Date: Tue, 30 Mar 93 05:00:19 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #385 To: Space Digest Readers Precedence: bulk Space Digest Tue, 30 Mar 93 Volume 16 : Issue 385 Today's Topics: 25 kg. to Venus, how much would it cost? Breathing 100 atm. of anything Coral and Dyson Sphere.. Gravity waves, was: Predicting gravity wave quantization & Cosmic Noise JPL's Public Access Site KRYSTAL in separate orbit? Magellan Update - 03/22/93 Making Those Venusian Oceans Nova Graphics (was Re: Space Posters, and where to get them?) Question on Cassini Radar (3 msgs) Sources for post-doctoral positions in Space Physics Space Calendar - 03/27/93 Speculation: the extension of TCP/IP and DNS into large light lag enviroments (3 msgs) Terraforming Venus cheaply? NO! (2 msgs) Timid Terraformers (was Re: How to cool Venus) viking cdrom question 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: Mon, 29 Mar 1993 14:38:38 GMT From: Keith Mancus Subject: 25 kg. to Venus, how much would it cost? Newsgroups: sci.space >I wrote: >> Sounds to me like there is a LOT of room for cost improvement on the >>low-mass end, unless the $20M figure is really a loss to the Russians >>and they just don't know it (quite possible)... >> It seems to me that a cost of < $1M per launch would have a great effect >>on the viability of this type of mission. Granted, there are some benefits >>to scale here, but I don't believe that decreases cost by a factor of 10. henry@zoo.toronto.edu (Henry Spencer) writes: >[Answer stating that increased *number* of flights could bring down costs > by a very large factor] Sorry, Henry, I didn't make my statement clear. I meant that flying a larger booster would not bring costs down that much. In other words, launching 1700 kg to escape velocity is probably cheaper ($/lb) than launching 75 kg (assuming each one is a single flight on an existing booster), but not 10X cheaper. I wasn't talking about benefits of scale due to a larger number of flights, or mass production of the booster. -- Keith Mancus | N5WVR | "Black powder and alcohol, when your states and cities fall, | when your back's against the wall...." -Leslie Fish | ------------------------------ Date: 29 Mar 93 15:36:42 GMT From: gawne@stsci.edu Subject: Newsgroups: sci.space,sci.astro,sci.physics In article , et@teal.csn.org (Eric H. Taylor) writes: [Quoting Nikola Tesla] > "I hold that space cannot be curved, for the simple reason that it can have > no properties." > "Of properties we can only speak when dealing with matter filling the > space. To say that in the presence of large bodies space becomes curved, > is equivalent to stating that something can act upon nothing. I, > for one, refuse to subscribe to such a view." - Nikola Tesla OK, how about we just return to first principles? The argument of GR, as I recall from graduate school, is that the metric of spacetime can't be represented by constants in the presence of masses. The metric has to be represented by differentials. Now the 'normal' conditions of geometry where metrics have to be represented by differentials are curves. Thus the efforts to explain GR in non- mathematical language have seized on this similarity to say that space is curved in the presence of masses. I'm sure that some of our more adroit contributors have a deeper under- standing of this than I. Still, this may help some of the people out there who are getting lost in the words without a background in the Reimanian geometry. -Bill Gawne, Space Telescope Science Institute "Forgive him, he is a barbarian, who thinks the customs of his tribe are the laws of the universe." - G. J. Caesar ------------------------------ Date: 29 Mar 93 16:43:20 GMT From: Doug Loss Subject: Breathing 100 atm. of anything Newsgroups: sci.space It seems to me that the major problem, everything else assumed to be OK, is that at 100 atm. the viscosity of _any_ gasses is such that a human diaphragm will fatigue and cease functioning, causing suffocation regardless of partial pressures, etc. Doug Loss ------------------------------ Date: 29 Mar 1993 12:10:43 GMT From: David Toland Subject: Coral and Dyson Sphere.. Newsgroups: sci.space In article <1993Mar27.114023.1@aurora.alaska.edu>, nsmca@aurora.alaska.edu writes: > So I am wierd.. > I once had an idea on how to create a dyson (sp, or dysean?) Sphere, using a > genetically engineered animal similar to a coral.. Namely using a selection of > coral and other contructs to construct the sphere (the growth of the coral > would have to be speeded up thou), one group to collect and convert the base > materials, the others group to build it.. Now to figure out how it would be > able to hanbdle space and it might work sometime in the future.. > > A sphere or a Ringworld base structure is more like it, not sure how to do the > rest.. But Im sure someone can figure this out.. > > How to get the coral to build the "reef" in the shape wanted?? Assuming you've solved the problem of making the raw materials available in sufficient quantity, and have solved all the other problems, can we get some rate estimates? If you calculate the surface area of the sphere, the most optimistic growth rates, and initial colony size, how long will the sphere take to complete, and how does it compare with the current age of the Universe? I haven't done any calculations on this, but I strongly suspect that the answers would be amusing. I doubt most people can easily conceive of the scale of a Niven Ring, much less a Dyson Sphere of the same radius! -- -------------------------------------------------------------------------- All opinions are MINE MINE MINE, and not necessarily anyone else's. det@phlan.sw.stratus.com | "Laddie, you'll be needin' something to wash | that doon with." ------------------------------ Date: Mon, 29 Mar 1993 15:52:47 GMT From: Nick Haines Subject: Gravity waves, was: Predicting gravity wave quantization & Cosmic Noise Newsgroups: sci.space,sci.astro,sci.physics,alt.sci.planetary Geez, I didn't mean to start anything quite this wordy. The point of my illustration is that when physicists talk of spacetime being curved, what they mean is this sort of curvature: "if we drew a circle on it and measured its circumference, we wouldn't get 2\pi r" (which spheres and saddles have but cones and cylinders don't), which does _not_ imply the actual existence of a higher-dimensional space which spacetime is curved `in'. Because such a space is not required by the theory, and can not have _any_ physical consequences (because all observables are embedded in the spacetime), why consider it? Why discuss it? Sure, I can propose that spacetime is embedded in a 17-trillion dimensional space, but what does it win me. The flat thing which this curvature is `measured against' is a notional flat space in which the area of all circles is 2\pi r. Also, spacetime topologies are theoretically possible which cannot be embedded in higher dimensions. Oh, and to speak of a sphere `curving downwards' and a saddle `curving upwards' is very misleading; it implies that if you look at a sphere from `the other side' it looks like a saddle. Absurd: the angles of a triangle drawn in a surface don't change if you turn the surface over. Speak instead of positive and negative curvature. Nick Haines nickh@cmu.edu ------------------------------ Date: 29 Mar 1993 16:30 UT From: Ron Baalke Subject: JPL's Public Access Site Newsgroups: sci.space,sci.astro,alt.sci.planetary In article <28MAR199322443311@cc.utah.edu>, beezer@cc.utah.edu (BEEZER) writes... >In article <26MAR199317124999@kelvin.jpl.nasa.gov>, baalke@kelvin.jpl.nasa.gov (Ron Baalke) writes... >>From the "JPL Universe" >>March 26, 1993 >> >>Public access computer site spurs worldwide interest in Lab activities > >> -- Those with a computer and a modem may call 354-1333, > >Umm, forgot the area code, didn't we? {grin} > The number with area code is 818-354-1333. I posted the article as is, but forgot that since it came from JPL's in house newspaper, some of the info is localized. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Don't ever take a fence /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | down until you know the |_____|/ |_|/ |_____|/ | reason it was put up. ------------------------------ Date: Mon, 29 Mar 93 13:04:51 GMT From: George Hastings Subject: KRYSTAL in separate orbit? Newsgroups: sci.space ...interesting question relayed from the CompuServe SPACEFORUM: 23-Mar-93 09:56:44 Sb: KRISTAL DUMPED? Fm: 71461.34@compuserve.com To: ALL To any of you that run orbital elements you might look at what the latest set gives for Kristal and MIR. They are different. While running a routine check on them it appears that 1)The russians have seperated Kristal from MIR. This could be to do microgravity work (darn a free flying microgravity platform wish someone would think of that here) 2)Space Command has made a goof. I bumped a message to MIR last night in a query. NO reply so far. I'll listen for MIR/Kvant telem and see what gives. Any of the Russian experts here got a clue? Robert G. Oler ____________________________________________________________ | George Hastings ghasting@vdoe386.vak12ed.edu | | Space Science Teacher 72407.22@compuserve.com | If it's not | Mathematics & Science Center STAREACH BBS: 804-343-6533 | FUN, it's | 2304 Hartman Street OFFICE: 804-343-6525 | probably not | Richmond, VA 23223 FAX: 804-343-6529 | SCIENCE! ------------------------------------------------------------ ------------------------------ Date: 29 Mar 93 14:11:07 GMT From: Gary Coffman Subject: Magellan Update - 03/22/93 Newsgroups: sci.space,sci.astro,alt.sci.planetary In article <1oveva$iif@access.digex.com> prb@access.digex.com (Pat) writes: > >Evena simple morse-pulsing. Certainly, low rate, but good for filling >in some of those remaining blank spaces that magellan never imaged. I can see it now, some guy at DSN wearing cans and copying numbers with a mill. Somehow I think the signals are a bit too weak for such antique methods. Morse encoding is not well suited for machine decoding at extremely weak levels. Gary -- Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary 534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary Lawrenceville, GA 30244 | | ------------------------------ Date: 29 Mar 93 11:53:13 GMT From: Del Cotter Subject: Making Those Venusian Oceans Newsgroups: sci.space In article flb@flb.optiplan.fi ("F.Baube[tm]") writes: >Someone suggested importing hydrogen to get > > CO2 + 4 H -> C + 2 H2O As Nat Reynolds said... "speaking." >Well, gee, the *Sun* has lots of hydrogen >floating around free for the asking .. sarcasm ON Sure, Jupiter's gravity well isn't *nearly* deep enough... sarcasm OFF The "cheapest" places to get hydrogen and slam it into Venus would be the furthest out (lower delta V), smallest (ditto) and coldest (lowest refrigeration cost). Uranus and Neptune come out neck and neck at about 2e28 J for about 4e19 kg H2. Fogg plumped for Uranus but I prefer Neptune for a number of reasons, but there's no reason not to set up operations around /both/ worlds. The Sun has one great advantage as a hydrogen source: It's a VERY high energy environment. One great disadvantage: It's a VERY VERY high energy environment. -- ',' ' ',',' | | ',' ' ',',' ', ,',' | Del Cotter mt90dac@brunel.ac.uk | ', ,',' ',' | | ',' ------------------------------ Date: 29 Mar 93 04:35:42 GMT From: Bill Higgins-- Beam Jockey Subject: Nova Graphics (was Re: Space Posters, and where to get them?) Newsgroups: sci.space In article <1993Mar27.041249.28500@sol.UVic.CA>, rborden@ugly.UVic.CA (Ross Borden) writes: > In article <1993Mar25.102746.1@aurora.alaska.edu> nsmca@aurora.alaska.edu writes: >>Wiers question, where is a good place to get Space Posters??? > > Try Nova Graphics in Tuscon, AZ. They have some nice prints of spacescapes > by artists like Kim Poor and Alan Bean. They're good quality, but a bit > pricey ($30-$80) because they're all limited editions. Sorry, can't give > you the address, my catalog is at home. I second the motion, Mr. Chairman. Their address is: Nova Graphics P.O. Box 37197, Tucson, AZ 85740 (800)821-1989 extension 1014 Moira Higgins on astronomy: Bill Higgins "I can always find Orion. Fermi National Accelerator Laboratory Besides that the Moon Internet: HIGGINS@FNAL.FNAL.GOV is my only other specialty." Bitnet: HIGGINS@FNAL.BITNET ------------------------------ Date: Mon, 29 Mar 1993 12:45:08 GMT From: Schroder S Subject: Question on Cassini Radar Newsgroups: sci.space This is a request for more information about the Cassini radar. I understand that Titan is going to be scanned with some kind of radar, but will this be a Synthetic Aperture Radar? Furthermore, I wonder whether a "complete Titan mapping" program will be carried out, since (radar-)imaging can only be done during short fly-by's of this moon. Are we going to see the same kind of pictures as the Magellan ones? Stefan Schroder. << sschrod@cs.vu.nl or schroder@bio.vu.nl >> ------------------------------ Date: 29 Mar 1993 16:34 UT From: Ron Baalke Subject: Question on Cassini Radar Newsgroups: sci.space In article , sschrod@cs.vu.nl (Schroder S) writes... > >This is a request for more information about the Cassini radar. >I understand that Titan is going to be scanned with some kind of >radar, but will this be a Synthetic Aperture Radar? Cassini's radar mapper will use SAR, and is very similar to the one that Magellan currently uses. >Furthermore, I wonder whether a "complete Titan mapping" program >will be carried out, since (radar-)imaging can only be done during >short fly-by's of this moon. Are we going to see the same kind of >pictures as the Magellan ones? Cassini will make about 30 close flybys of Titan, and will make a mapping swath on each encounter. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Don't ever take a fence /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | down until you know the |_____|/ |_|/ |_____|/ | reason it was put up. ------------------------------ Date: 29 Mar 93 10:27:54 -0600 From: Bill Higgins-- Beam Jockey Subject: Question on Cassini Radar Newsgroups: sci.space In article , sschrod@cs.vu.nl (Schroder S) writes: > This is a request for more information about the Cassini radar. I don't have it handy, but there was a substantial overview of this radar published in *Proceedings of the IEEE* (that's "Institute of Electrical and Electronic Engineers") sometime in the past two or three years. Maybe one of the radar people reading this list can provide the exact citation. > I understand that Titan is going to be scanned with some kind of > radar, but will this be a Synthetic Aperture Radar? Yes. I wonder whether they have any plans to point it at Saturn. Would it show anything? And will they use the radar on other satellites which are not cloudy? > Furthermore, I wonder whether a "complete Titan mapping" program > will be carried out, since (radar-)imaging can only be done during > short fly-by's of this moon. Are we going to see the same kind of > pictures as the Magellan ones? You are correct. The SAR will scan only a few skinny little strips of Titan's surface. Cassini will not orbit Titan, so the radar can only be used on a few occasions when its Kronian orbit (I saw this word in an astronomy paper the other day, I couldn't wait to use it) brings it close to Titan. It will still be better than pictures of a featureless orange tennis ball! 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: 29 Mar 93 04:47:28 GMT From: Dinesh Das Subject: Sources for post-doctoral positions in Space Physics Newsgroups: sci.research.careers,sci.engr,sci.engr.mech,sci.geo.fluids,sci.physics,sci.research,sci.space Hello, excuse me if I am posting to the wrong groups (and tell me where I should post it). I am looking for sources where I can find job advertisements for my wife who will be completing a PhD in space plasma physics. I would be interested in the names of any professional magazines, journals, or similar stuff that have post-doctoral or other PhD job ads in the areas of -- space physics -- numerical simulation -- fluid mechanics/dynamics -- fusion -- plasma physics -- oceanography and related areas. Please send me email if you can help me. Regards, Dinesh -- Dinesh Das Dept. of Computer Sciences, Univ. of Texas at Austin ddas@cs.utexas.edu Austin, TX 78712-1188 (512) 471-9721 "Life is uncertain - eat dessert first" ------------------------------ Date: Mon, 29 Mar 1993 13:32:35 GMT From: "William S. Werner" Subject: Space Calendar - 03/27/93 Newsgroups: sci.space,sci.astro,sci.space.shuttle,alt.sci.planetary The Delta II launch was scheduled for Sunday March 28, but was delayed due to upper level winds......so the plan is to try tonight, March 29, the window is from 10:09 PM to 10:37 PM Bill : ------------------------------ Date: Mon, 29 Mar 93 11:45:01 BST From: Greg Stewart-Nicholls Subject: Speculation: the extension of TCP/IP and DNS into large light lag enviroments Newsgroups: alt.internet.services,sci.space In <1p23h8INNnqi@gap.caltech.edu> M. Sean Bennett writes: >The Moon, Mars, etc. are "claimed for all mankind". By whom ?? ,I mean by this, who has the authority to issue such a proclamation. More importantly, who can enforce it ? ----------------------------------------------------------------- .sig files are like strings ... every yo-yo's got one. Greg Nicholls ... nicho@vnet.ibm.com (business) or nicho@olympus.demon.co.uk (private) ------------------------------ Date: 29 Mar 93 14:27:03 GMT From: Gary Coffman Subject: Speculation: the extension of TCP/IP and DNS into large light lag enviroments Newsgroups: alt.internet.services,sci.space In article <1p23h8INNnqi@gap.caltech.edu> sean@ugcs.caltech.edu (M. Sean Bennett) writes: >>Why is it a dangerous precedent? Should NASA or the CIS be building bases >>that aren't under any jurisdiction? > >It is my fault for not making myself clearer. > >The Moon, Mars, etc. are "claimed for all mankind". > >The dangerous precedent is the exporting of our national bigotries - irespective >of the nation involved. > >What is this COPOUS treaty you speak of? That's the treaty that "claims space as the common heritage of mankind", and incidently requires all profits from space exploitation be *shared* equally with all mankind regardless of the efforts exerted to make space profitable. Fortunately, the US didn't ratify that treaty, thanks in large part to the L5 society's efforts. Ratification would have spelled doom for all private capitalist operations in space. Gary -- Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary 534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary Lawrenceville, GA 30244 | | ------------------------------ Date: Mon, 29 Mar 1993 14:28:42 GMT From: Keith Mancus Subject: Speculation: the extension of TCP/IP and DNS into large light lag enviroments Newsgroups: alt.internet.services,sci.space >>What is this COPOUS treaty you speak of? pgf@srl03.cacs.usl.edu (Phil G. Fraering) writes: > A treaty that gave space "to all mankind;" literally, it gave _any_ nation > on the face of the earth veto power over anything done by anyone up there. > Go look up the COPOUS treaty and the debate surrounding it before you > come back to flame. Please. I was under the impression that the US had not signed this treaty. Right or wrong? -- Keith Mancus | N5WVR | "Black powder and alcohol, when your states and cities fall, | when your back's against the wall...." -Leslie Fish | ------------------------------ Date: 29 Mar 93 12:08:11 GMT From: Del Cotter Subject: Terraforming Venus cheaply? NO! Newsgroups: sci.space rabjab@golem.ucsd.edu (Jeff Bytof) writes: >This discussion of terraforming Venus has really begun to fascinate me. >What is especially intriguing is the possibility that the kickoff >in the process could be the simple injection of microorganisms into >the atmosphere of Venus. In terms of available technology, getting >a small package to Venus would be reasonably simple. The major problem, of >course, would be the technical advances to engineer organisms that >could survive the conditions on Venus as they change, and have >them perform useful activities, such as fixing the atmosphere in solid >form. Uh, small reality check. Genetic engineering may work wonders in the next few decades, but no bugs are ever going to live on what's in the upper Venerian atmosphere. We're going to have to drop trace elements on them from above /all the time/ or nuke dust into the upper atmosphere from below - /all the time/. The days of Jerry Pournelle's "we could probably get the job done this century [for the cost of] a medium sized war" (from 'A Step Further Out') are long behind us. >We are definitely looking at a long term project, Right, like industrialise the rest of the solar system first, before tackling the tough nuts. >but work >to construct a viable set of organisms could be done incrementally over >an extended period of time. Testing the actual organisms might be >possible at a facility like NASA/Ames, in a simulator designed to >mimic Venus. Sure, no reason not to start right now. I believe some work has already been done breeding superstrains of /cyanidium caldarum/ for Venerian conditions. -- ',' ' ',',' | | ',' ' ',',' ', ,',' | Del Cotter mt90dac@brunel.ac.uk | ', ,',' ',' | | ',' ------------------------------ Date: 29 Mar 93 13:37:21 GMT From: Paul Dietz Subject: Terraforming Venus cheaply? NO! Newsgroups: sci.space In article mt90dac@brunel.ac.uk (Del Cotter) writes: > The days of Jerry Pournelle's > > "we could probably get the job done this century [for the cost of] a > medium sized war" (from 'A Step Further Out') > > are long behind us. That's really humorous, when one considers that the energy required to separate all the CO2 in Venus's atmosphere to carbon and oxygen equals all the sunlight hitting the planet for 500 years (and, beyond that, photosynthesis is only about 1% efficient in practice, and never mind the reoxidation of reduced material). My favorite Pournelle column was "Love That Shuttle!", which appeared in Analog shortly after the first launch, tooting the horn of low cost to orbit via this wonderful machine. Yet another confirmation that science fiction is a poor place to learn science. Paul ------------------------------ Date: 29 Mar 93 14:33:26 GMT From: Gary Coffman Subject: Timid Terraformers (was Re: How to cool Venus) Newsgroups: sci.space In article rabjab@golem.ucsd.edu (Jeff Bytof) writes: >In article <93085.002514GRV101@psuvm.psu.edu> Callec Dradja writes: > >>My proposal, I feel, makes more sense in that it is slower and more >>managible. I propose using organisms to fix the CO2 into a solid form. >>Someone suggested carbonate rocks which sound like a good idea to me. > >I like that. Perhaps develop enzymes that will convert CO2 and various >other gases absorbed into an organism into fullerenes and "caged >molecules". Maybe even have the enzymes sort the gases that go inside >the buckyballs! Then the filled buckyballs are excreted and eventually >drift down to the surface of Venus? I don't know what the stability >of buckyballs at Venusian surface temperatures are. Haven't fullerenes >been discovered in rock deposits and by radio astronomers? Organisms that can exist without water, and at 860 degrees, seem to be the problem here. Natural buckyballs have been discovered in rocks that showed signs of being struck by lightning. Buckyballs can form under less extreme conditions than diamond films, but not by much. Ideally, the carbon in the Venusian atmosphere could be plated out on the surface as diamond film. *Then* there'd be an incentive to go to Venus. :-) Gary -- Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary 534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary Lawrenceville, GA 30244 | | ------------------------------ Date: 29 Mar 93 13:07:48 GMT From: Matthew Zenkar Subject: viking cdrom question Newsgroups: sci.space Can anyone tell me where the pictures of the "face on Mars" and the "pryamids of mars" are located in the cdrom library that is on line at explorer.arc.nasa.gov. I would appreciate it if you could tell me the volume, directory, picture (raw data picture) number, etc. E-mail responses would be greatly appreciated. Thank you in advance. Matthew Zenkar mz@moscom.com or mz@crl.com ------------------------------ End of Space Digest Volume 16 : Issue 385 ------------------------------