Date: Fri, 18 Sep 92 05:00:43 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #213 To: Space Digest Readers Precedence: bulk Space Digest Fri, 18 Sep 92 Volume 15 : Issue 213 Today's Topics: Clinton and Space Funding (2 msgs) Craters of Venus Inventory Drop nuc waste into sun Ethics of Terra-forming (2 msgs) Hubble's constant (2 msgs) Ion for Pluto Direct was Re: Pluto Direct Moving Venus Nasa's Apollo rerun Pluto Direct Propulsion Options (2 msgs) Pulsing rocket engines PUTTING VENUS IN AN ORBIT SIMILAR TO THE ORBIT OF THE EARTH (2 msgs) Space Platforms (political, not physical :-) Two-Line Orbital Element Set: Space 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: 16 Sep 92 14:33:09 GMT From: clements@vax.ox.ac.uk Subject: Clinton and Space Funding Newsgroups: sci.space,sci.astro In article <92258.120700DOCTORJ@SLACVM.SLAC.STANFORD.EDU>, DOCTORJ@SLACVM.SLAC.STANFORD.EDU (Jon J Thaler) writes: > sysmgr@king.eng.umd.edu (Doug Mohney) says: > > I suspect that the spin-off argument is about as bogus for military research > as it is for other fields (eg, the SSC). For example, unclassified work > on laser guide stars was proceeding at the same time that the SDIO was > pursuing its own program. Needless to say, the budget for the former was > vastly smaller than for the latter. My conclusion: If you want some benefit, > then go for it, but don't hope that by doing some unrelated work at much > greater expense you'll be lucky. > The only reason that the laser guide star work was declassified is that they've got a better and more effective method already developed. Research procedes better when conducted in an open unclassified environment. This is one *good* reason why military research does not generally work as well. -- ================================================================================ Dave Clements, Oxford University Astrophysics Department ================================================================================ clements @ uk.ac.ox.vax | Umberto Eco is the *real* Comte de dlc @ uk.ac.ox.astro | Saint Germain... ================================================================================ ------------------------------ Date: 16 Sep 92 13:43:05 GMT From: "Ethan T. Vishniac" Subject: Clinton and Space Funding Newsgroups: sci.space,sci.astro,talk.politics.space,alt.politics.bush,alt.politics.clinton The summary says it all. If there were some content to this then some political newsgroup would do. As it is, then only talk.liberal.bashing would seem appropriate. Maybe Mr. Vignes could create such a group. In any case there seems to be nothing in this relevant to astronomy. -- "Quis tamen tale studium, quo ad primam omnium rerum causam evehimur, tamquam inutile aut contemnendum detractare ac deprimere ausit?"-Bridel Ethan T. Vishniac, Dept. of Astronomy, The University of Texas at Austin Austin, Texas, 78712 ethan@astro.as.utexas.edu ------------------------------ Date: 17 Sep 92 11:03:49 GMT From: Ron Baalke Subject: Craters of Venus Inventory Newsgroups: sci.space,alt.sci.planetary ==================== Craters of Venus September 16, 1992 ==================== The USGS inventory of the craters of Venus is now available as a text file. This file contains the text of Schaber's Appendix A from his "JGR-Planets" paper, but it can easily be turned into a database or spreadsheet. The file can be retrieved using anonymous ftp from: ftp: ames.arc.nasa.gov (128.102.18.3) user: anonymous cd: pub/SPACE/MAGELLAN file: craters.txt ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Quiet people aren't the /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | only ones who don't say |_____|/ |_|/ |_____|/ | much. ------------------------------ Date: 17 Sep 92 06:54:18 GMT From: Nick Janow Subject: Drop nuc waste into sun Newsgroups: sci.space hangfore@spf.trw.com (John Stevenson) writes: > Why not drop all the longlived nuclear waste into the sun to permanently > dispose of it. The waste is a *very* expensive problem that will otherwise be > with us (children's children to the nth power) for along time. > > .... > > So, oh wise ones, enlighten me. What am I missing? Thanks Simple: that mass of transuranics isn't waste, it's a valuable resource we simply haven't developed a market for...yet. Politicians, supported by ignorance, have made it difficult to do anything with the "waste". From an engineering standpoint, that "waste" is a compact source of high-level energy, with many uses. It can sterilize/preserve foods better than toxic chemicals, it can provide safe heat for remote areas, it could sterilize sewage, or it could be "burned" in a different reactor, providing more energy. Sending nuclear waste into the sun is like dumping platinum in the ocean because it isn't the metal you wanted at the time (gold). Was it the Spaniards who did that off the S.American coast? Think of how many people threw out "trash" such as baseball trading cards, or any other collectibles. "They threw away transuranics? WERE THEY CRAZY?" -- Nick_Janow@mindlink.bc.ca ------------------------------ Date: Thu, 17 Sep 1992 03:51:22 GMT From: David Knapp Subject: Ethics of Terra-forming Newsgroups: sci.space In article henry@zoo.toronto.edu (Henry Spencer) writes: >In article <5tzn26k.tomk@netcom.com> tomk@netcom.com (Thomas H. Kunich) writes: >>We don't know if there is or if there isn't any life on Mars. > >We clearly need to find out before we do any major alterations. > >>What is to prevent there being some sort of life-form analogous to >>the vent creatures of the deap oceans living subterrameanly at >>some depth at which water, heat and chemical sustanance is available >>from interior heating? > >What is to prevent such life on Earth? Maybe we are unknowingly wiping >it out right now. We always have to act on imperfect knowledge, but we >should make a reasonable effort. > >Consider also that any present life on Mars is probably having a hard >time of it. Maybe some environmental changes are just what is needed >to *save* it from extinction. > >>What ever life there might be on Mars, or anywhere else for that matter, >>at least has the right to exist. Is man God, to destroy other life-forms >>without much measured forethought? > >Actually, the correct line is "Is man Nature?". Nature recognizes no >"right to exist"; extinction was a routine event long before we arrived. But one question most people forget to ask is 'who was doing the extincting?' How many species do you know of that: 1) Can think about long term consequences of their actions. 2) Are capable of at least some degree of terraforming. 3) Causes mass extinctions on a daily basis. 4) Should, many times, "know better" 4) Has the capability to wipe out all life currently known in one fell swoop. 5) Controls their enviroment, in all aspects, to suit their needs. 6) Expands to live in every environment on the planet. 7) etc. The list can get very long. Point to anything that differentiates us from all other life. After considering all these things, we have to conclude that mankind is not just your average-joe species is just carrying a long with the rest of them. We are a *major* influence here like no othe species before us. Mankind is most certainly a special case when you point to 'nature.' >Are we Nature? Well, yes, we're part of it. We should act cautiously, >especially given our relative ignorance That is the understatment of the day (IMO) The power that mankind currently has along with the collective stupidity he posesses, I must liken to giving a toddler an AK-47 and hoping for the best. You can see the bullet holes all around you. >, and bearing in mind that it's >hard to reverse extinction... but there is nothing morally wrong about >making changes. Nature does it all the time. *We* decide what is moral. Just one man saying so isn't enough. *We* are also not nature. What you see in nature is nothing near the result of a 'relatively ignorant' species. >-- >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 Your .sig is quite relevant here. -- David Knapp University of Colorado, Boulder Perpetual Student knapp@spot.colorado.edu ------------------------------ Date: 17 Sep 92 07:25:24 GMT From: Bertil Jonell Subject: Ethics of Terra-forming Newsgroups: sci.space In article <1992Sep17.035122.11105@ucsu.Colorado.EDU> knapp@spot.Colorado.EDU (David Knapp) writes: >But one question most people forget to ask is 'who was doing the extincting?' > >How many species do you know of that: >3) Causes mass extinctions on a daily basis. >5) Controls their enviroment, in all aspects, to suit their needs. >6) Expands to live in every environment on the planet. All species that have the capability of doing so. To make a very silly example, if mooses suddenly would become capable of living anywhere, escape any predator and plan for the future, I'd expect them to use all this (especially the last thing) to exapand and spread to their utmost limits. >After considering all these things, we have to conclude that mankind is not >just your average-joe species is just carrying a long with the rest of them. Consistent along the latter history of mankind has been an inflated sense of self-importance. It seems to have started with the 'in gods image' idea, moved on to 'crown of creation' and 'lord of nature' and then on to 'most dangerous animal', 'controls their enviroment, in all aspects, to suit their needs', 'expands to live in every environment on the planet' and 'most disruptive influence in the history of the planet'. The common theme of all this is obviously a self-congratulatory "We're Special!"(1). >We are a *major* influence here like no othe species before us. Changed the environment more than the blue-green algae did? reformatted quotes: >....Mankind is most certainly a special case when you point to 'nature.'.. >..The power that mankind currently has....You can see the bullet holes all >around you....*We* decide what is moral....What you see in nature is nothing >near the result of a 'relatively ignorant' species. >David Knapp University of Colorado, Boulder (1) This also has some connection to the question "What's the difference between George Bush and Noam Chomsky?" where the correct answer is that it is very small. Both believe that the US is the mightiest country in the world. Both believe that US domestic politics drives all international politics. Both believe that the world as it looks today is a creation of the US. 1/2:) -bertil- -- "It can be shown that for any nutty theory, beyond-the-fringe political view or strange religion there exists a proponent on the Net. The proof is left as an exercise for your kill-file." "This is the famous Hasan B Mutlu-trigger, insert it in your .sig file today!" ------------------------------ Date: 16 Sep 92 15:25:41 GMT From: Richard J Brooks Subject: Hubble's constant Newsgroups: sci.space Hi Gang I read this past week about a researcher stating that some measurements indicate that the HUBBLE constant is changing with time. The acticle stated that the change was fast enought that a remeasurement in 2 or 3 year would verify this. Could any of you on the NET comment about this. (As a side comment - If my memory is correct, Hubble's constant is used in determining distances in space. Does this mean that the size of the universe is changing?) ----------------------------------------------------------------------------- Richard J Brooks | To know wisdom and instruction Brooks%EWSVAX.decnet@MDCGWY.MDC.COM | To discern the saying of understanding | Proverbs 1:2 ----------------------------------------------------------------------------- ------------------------------ Date: 17 Sep 92 01:21:16 GMT From: Steinn Sigurdsson Subject: Hubble's constant Newsgroups: sci.space In article <1992Sep16.152541.1@ewsvax.mdcbbs.com> brooks@ewsvax.mdcbbs.com (Richard J Brooks) writes: Hi Gang I read this past week about a researcher stating that some measurements indicate that the HUBBLE constant is changing with time. The acticle stated that the change was fast enought that a remeasurement in 2 or 3 year would verify this. Could any of you on the NET comment about this. Sure, not only is the Hubble "constant" (sic) changing in time, the value is in fact oscillating, the frequency of oscillation increasing with time while the amplitude appears to have decreased slightly... ;-) Seriously: there is a deceleration paramater, a non-zero value of which can be considered equivalent to a changing hubble constant, and it might even be detectable this decade, however, there is (still) and uncertainty of factor two in the present value of the hubble constant, so don't bet on it. | Steinn Sigurdsson |I saw two shooting stars last night | | Lick Observatory |I wished on them but they were only satellites | | steinly@lick.ucsc.edu |Is it wrong to wish on space hardware? | | "standard disclaimer" |I wish, I wish, I wish you'd care - B.B. 1983 | ------------------------------ Date: Thu, 17 Sep 1992 04:36:27 GMT From: Dave Tholen Subject: Ion for Pluto Direct was Re: Pluto Direct Newsgroups: sci.space Greg Macrae writes: > Well, you're actually wrong on all counts. The biggest problem that ion > thruster technology faces is being unproven in the field. In a mission > that is such high risk as planetary robotic exploration, no one want to > be the first to use ion propulsion. For a Pluto mission, ion thrusters > enable the mission. The Aerospace Analysis Office here published a study > that showed ion thrusters could place twice the payload in orbit (or on) > Pluto that chem. rockets could fly past Pluto and ion did it in less than > 1/2 the time with the same Leo mass! The study assumed a Jupiter slingshot > for the chem. system and not for ion. In general, ion has time and mass > advantages for all missions beyond the asteroid belt. At Pluto's orbit, > the advantage is very significant. As for on-going work with ion thrusters, > the focus is currently on station keeping and other near earth satellite > applications in hopes of establishing the track record of success required > for serious consideration for interplanetary missions. Research is funded at > fairly low levels at both Lewis Research Center and JPL. Hughes is marketing > flight qualified ion thrusters for station keeping use. The current Pluto flyby mission design calls for chemical rockets and NO Jupiter flyby, and the flight time is about seven years. Your posting seems to be claiming that an ion drive can place twice the payload into orbit around Pluto with a flight time of about 3.5 years. If this were true, I'm quite certain that the Outer Planets Science Working Group would have heard of it. Agreed that ion has FLIGHT time and mass advantages beyond the asteroid belt, but once we get there, we'd like to have some time to study the object, and a fast ion drive flyby provides less time to do that. True, ion can be used to slow down, even enough to go into orbit, but then the flight time increases, and the estimates we were given were much, much longer than 3.5 years. And I wouldn't go so far as to say that ion drive enables a Pluto mission. The implication is that without ion drive, you can't do a Pluto mission, and that simply isn't true. We've looked at several mission options all based on chemical rockets. Many of them are quite attractive. Ion drive options are also attractive, but riskier. Therein lies the Catch 22. Regarding my comment about development of ion drive not being funded, I was referring to the type of long duration mechanism proposed for the TAU mission. The station-keeping application is rather different than that needed for interplanetary propulsion, which is also long duration, continuous duty cycle. ------------------------------ Date: Wed, 16 Sep 1992 22:44:59 GMT From: David Knapp Subject: Moving Venus Newsgroups: sci.space In article <16SEP199205563870@reg.triumf.ca> vincent@reg.triumf.ca (pete) writes: >Hey, that's what we like to see; a good practical civil >engineering problem. (^: So hey: here's the cheap easy way >to do it (and you get Mars in a warmer orbit as a bonus). >Just build a whole bunch of big electron accelerators, >and fire off kiloamps of e+ at Mars and a similar quantity >of e- at Venus. After a few centuries of constant current, >the E field will start pulling the 2 planets toward each >other, moderating both their climates. Or maybe it will >just charge up their atmospheres, causing Venus to lose >a whole lot of unwanted cloud cover by repulsion. > This also guarantees lots of jobs for generations >of us accelerator folk. (^: (^: (^: > >=========================================================================== >Now what we really need is a scheme Pete Vincent >for Mars and Venus to trade atmospheres. > It's good to finally see some reasonable arguments here! -- David Knapp University of Colorado, Boulder Perpetual Student knapp@spot.colorado.edu ------------------------------ Date: 16 Sep 92 07:30:13 GMT From: "John A. Weeks III" Subject: Nasa's Apollo rerun Newsgroups: sci.space In article keithley@apple.com (Craig Keithley) writes: > The gist of the report was that we goofed in our choice of going to the > moon. During the late 50s and early 60s, we were faced with the choice of > developing things like DynaSoar and MOL (these were Air Force) or going for > the moon shot. In retrospect, I think that there are a lot of people who feel this way. It is depressing to think of what might have been if the space program had continued along the X-15 path to space rather than the man-in-a-can program. Then again, one has to keep in mind that the US went to the moon only because we thought the Soviets would beat us to it. No cold war, no moon shot. I doubt that the US would have spent a similar amount of money on space without the cold war or the race to the moon. The real crime is that the US spent a ton of money going to the moon rather than spending the money on a space program. Once the moon goal was reached, everything came to a halt and the Apollo program was scrapped. -john- -- ============================================================================== John A. Weeks III (612) 942-6969 john@newave.mn.org Newave Communications, Ltd. ..!uunet!tcnet!newave!john ------------------------------ Date: 17 Sep 92 01:36:58 GMT From: Dave Tholen Subject: Pluto Direct Propulsion Options Newsgroups: sci.space,sci.astro,alt.sci.planetary > Wonder if there would be "snow" storms when Pluto's atmosphere freezes out, > or would just form frozen "dew" on the surface. Maybe both, as the gas > with the higher freezing point "snows" out before the gases with lower > freezing points condense out. (Do I remember correctly that there are > more than one gas in Pluto's atmosphere?) "Storm" is a relative term. Pluto's atmosphere is so thin that you'd never get anything like what we have on Earth. On the other hand, Voyager showed streaks on Triton, apparently driven by winds, even though Triton's atmosphere is about as thin as Pluto's. Whether Pluto also has winds is an excellent question. If the surface is isothermal, which could be the case if methane frost is everywhere, then there isn't much of a mechanism to drive winds, but if the darker regions are exposed rock, for example, then temperature differences could exist, thereby driving some weather on Pluto, so you might have something more than just the equivalent of dew forming. Yes, there are several gases in Pluto's atmosphere. Methane, nitrogen, and carbon dioxide have all been detected spectroscopically (the latter two only very recently). The vapor pressure of nitrogen is highest, followed by carbon dioxide, so nitrogen is probably the dominant gas. ------------------------------ Date: 17 Sep 92 01:41:42 GMT From: Dave Tholen Subject: Pluto Direct Propulsion Options Newsgroups: sci.space,sci.astro Josh Hopkins writes: > Do we need to worry about pulling another Titan? It would be kind of > embarrassing to dedicate a half billion, two probes and ten years of ops, only > to find out that Pluto's atmosphere is opaque :) I can assure you that Pluto's atmosphere is not opaque. At the limb, the optical depth might approach unity if Jim Elliot's haze layer model is correct (and there are good chances that it isn't correct), but at normal incidence, it is rather transparent. Why do you think we see a lightcurve, and a substantial one at that? ------------------------------ Date: 17 Sep 92 05:36:20 GMT From: Dave Rickel Subject: Pulsing rocket engines Newsgroups: sci.space In article <1992Sep16.130618.20179@access.digex.com>, mheney@access.digex.com (Michael K. Heney) writes: |> In article urf@icl.se (Urban F) writes: |> >Ali AbuTaha, of Dynamic Transients, is claiming that |> >pulsing-engine technology could enable the Shuttle to carry a |> >payload of 105.500 kg, as apart from 29.500 today, and also that |> >an Ariane 4:s first stage could become so efficient as to make it |> >a SSTO vehicle. |> |> I saw an abstract of a paper he wrote for the World Space Congress here in |> DC last month. He talks about "rectifying" the engine thrust to effectively |> double the Isp - for the SSME, that moves it from 455 to the 900 sec range. |> He claims (correctly; I assume) that you could launch without the SRBs, |> making the shuttle/ET combination an SSTO. Such Isp increases are bogus. It might be that he thinks he can get a dramatic increase in the thrust:weight ratio of the engines--a ratio of around 200:1 should be about right for eliminating the SRBs. The SSMEs have a thrust:weight ratio of about 60:1. david rickel drickel@sjc.mentorg.com ------------------------------ Date: 17 Sep 92 00:58:47 GMT From: David Smith Subject: PUTTING VENUS IN AN ORBIT SIMILAR TO THE ORBIT OF THE EARTH Newsgroups: sci.space I think we've found Dan Quayle's advisor on the Mars speech! -- David L. Smith smithd@discos.com or davsmith@nic.cerf.net ------------------------------ Date: Thu, 17 Sep 92 14:07:59 BST From: amon@elegabalus.cs.qub.ac.uk Subject: PUTTING VENUS IN AN ORBIT SIMILAR TO THE ORBIT OF THE EARTH > sustaining ecology on the planets (like Venus or Mars) whose present cosmic > parameters, to begin with do not allow the existence of life on them, seems > improbable and impractical. > Your statement is not correct. The current states of Mars and Venus, while associated with their origin at a closer distance to the sun are not fully constrained by that location. Even if moved, the dense CO2 atmosphere and H2 deficit will still be there for Venus. Venus would cool, but something has to be done to get rid of (or bury) the excess carbon. If Venus had been at Earth orbit billions of years ago, before it lost it's water, geochemistry might have done the trick. But it unfortuneately too late for that. Not to mention which, you could have nasty side effects like causing other planets to leave the solar system. As recent papers have shown, all 9 planets are in chaotic orbits. There are two time constants involved, neither of which has been identified. The solar system exhibits long term stability nonetheless, so it could be that only those proto planetary bodies which were at the right place relative to other protoplanets survived, ie were not kicked out of the solar club. If you moved Venus, all the resonances change drastically and there is no certainty whatever that the end result would look any thing at all like the current solar system. Of course, the Earth might make a nice Interstellar Generation Spaceship if we get fusion power going soon enough... ------------------------------ Date: 17 Sep 92 06:55:33 GMT From: Bertil Jonell Subject: Space Platforms (political, not physical :-) Newsgroups: sci.space,talk.politics.space,alt.politics.libertarian,alt.war In article <1992Sep16.054900.17022@techbook.com> szabo@techbook.com (Nick Szabo) writes: >* Privatize the radio spectrum and orbital slots, and disavow all > treaties (Sea, Moon, Antartica, etc.) that prohibit private > property and enterprise in frontier areas. That sounds almost as anti-social as when the Soviet union voided all international agreements (including the Geneva convention) or when the Mullas in Iran felt they were above worldly stuff like diplomatic status. If the US did something like that, and stepped somebody on the toes (like drowning out others transmissions, crowding out their satelites, and start drilling for oil in the Norwegian zone (or Russian zone, or Argentinean zone), I'd expect an international conflict on the level of at least trade war. >szabo@techbook.COM Tuesday, November third ## Libertarian $$ vote -bertil- -- "It can be shown that for any nutty theory, beyond-the-fringe political view or strange religion there exists a proponent on the Net. The proof is left as an exercise for your kill-file." "This is the famous Hasan B Mutlu-trigger, insert it in your .sig file today!" ------------------------------ Date: 16 Sep 92 20:49:42 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 47 1 22120U 92 61 A 92259.91666666 .00076267 00000-0 25599-3 0 136 2 22120 57.0011 92.2892 0008799 291.0911 351.7450 15.89483576 529 -- Dr TS Kelso Assistant Professor of Space Operations tkelso@afit.af.mil Air Force Institute of Technology ------------------------------ End of Space Digest Volume 15 : Issue 213 ------------------------------