Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from beak.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID ; Wed, 16 May 90 01:43:41 -0400 (EDT) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Wed, 16 May 90 01:43:11 -0400 (EDT) Subject: SPACE Digest V11 #405 SPACE Digest Volume 11 : Issue 405 Today's Topics: Re: Re: Why no ETs Call For Discussion: comp.lang.idl-pvwave Why do Ariane engines use water? Hubble Space Telescope Update - 05/15/90 Re: Vatican Connection Re: Venus Base Re: Terraforming Venus (was: Manned mission to Venus) ---------------------------------------------------------------------- Date: Tue, 15 May 90 18:54:11 EDT From: John Roberts Disclaimer: Opinions expressed are those of the sender and do not reflect NIST policy or agreement. Subject: Re: Re: Why no ETs Marc Arlen writes: >From: AZM@CU.NIH.GOV >The current, and forever into the future trend in world population is up. >Fortunately, this too is a self-limiting process. Rampant disease, grind- >ing poverty, and starvation will reduce the total number of humans on >Earth. More correctly, food-production capability tends to go up, and population tends to increase to the limit of the food supply, at least in many countries. The result is that disease, war, and starvation tend to be limiting factors unless some other artificial factor (such as birth control) is introduced. This factor seems to be proving effective in some countries. A number of poverty- stricken countries have an explosive growth rate partly because the technologically advanced nations provided them with modern medicine to lower the death rate, without doing much to encourage a corresponding lowering of the birth rate. >If you are on a camping trip in the wilderness, protected by a flimsy >nylon backpacking tent, and you discover,just around nightfall, that >you are directly in the path of a hungry, savage, salivating, snarling >pack of large, ferocious wolves, you do absolutely everything within >your power to render your presence, and the visibility of your pro- >tective shelter, and any possible odors, aromas, or fragrances that >you might be producing, and any and all possible sources of light >alien to the environment, and every single, possible sound however >minute, invisible, and then cringe in fear through the night hoping >that you will not be discovered, and the wolf pack will pass you by. While wolves have been known to attack humans, such incidents are very rare, and generally under highly unusual situations. A much better example for your point would have been bears - black bears will attack humans if they perceive a threat to themselves or their young, or while guarding a kill. Grizzly bears (Ursus horribilis, or "horrible bear") will attack much more readily, apparently sometimes just as a result of temper. I believe several hundred people are attacked by grizzlies every year. Bears will also approach humans to steal food, while traditionally one shepherd is considered sufficient to frighten the wolves away from a flock of sheep. It's sad that people tend to misjudge the relative hazards in nature, as well as man-made hazards. Many people will go out of their way to kill a harmless nonpoisonous snake, then pick up some small mammal dying of rabies (the main cause of rabies infection). In any event, any aliens who can manipulate the quantities of energy necessary for relativistic travel don't have to worry about any threat from us for a long time. > Derd Valpar > aka Marlen > AZM@NIHCU John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: 16 May 90 01:46:53 GMT From: caldwr!rfinch@ucdavis.ucdavis.edu (Ralph Finch) Subject: Call For Discussion: comp.lang.idl-pvwave CALL FOR DISCUSSION: creation of comp.lang.idl-pvwave [Sorry if this is the 2nd time you've seen this, our news system picked this week to act up] Please direct followups to news.groups This is to start a discussion about creating a group for a language called either IDL or PV-Wave (depending on whom you buy it from). Items to be discussed are primarily whether to create a new group, or rename the existing comp.lang.idl (see fuller explanation below) and the group name. Proposed Name: comp.lang.idl-pvwave Discussion period: Through June 1, 1990. Charter: An unmoderated newsgroup for discussing the programming language known as both Interactive [Data/Display] Language (IDL) and PV-Wave (Precision Visuals Workstation Analysis and Visualization Environment). Topics will be programming tips, techniques, and code exchanges, either full programs or fragments. A program archive site may be started; however that possibility will be discussed only after the proposed newsgroup is formed, not during the current discussion period. The proposed group is intended primarily to discuss numerical analysis, imaging, scientific visualization, etc. *as performed using the IDL/Wave language*; it is not intended to support discussions concerning those topics directly, as groups already exist for those purposes (e.g. sci.math.num-analysis). Background: There exist 2 very similar forms of the same language, IDL and PV-Wave. IDL is produced by Research Systems in Boulder, Colorado; PV-Wave by Precision Visuals also in Boulder. PV-Wave is derived from IDL, so for the purpose of this discussion they can be considered the same language, which I will refer to as IDL/Wave. The language is used both interactively and as a programming language for data analysis/reduction, display of data by means of 2- and 3-D plots, images, simple animation, etc. It runs on DEC and Sun workstations, and perhaps others. There currently exists the group comp.lang.idl, which was formed some time ago apparently for the purposes of discussing the Interface Description Language, which has other uses entirely than IDL/Wave. A while ago a discussion started on that group as to what comp.lang.idl was for. Three basic suggestions came out of that discussion: form a completely new group; rename comp.lang.idl to comp.lang.idl-pvwave; or use the group with its current name to talk about IDL/Wave. The last is undesirable because of the lack of name identification, see below. 1) Create new group: The advantage is that we don't "hijack" somebody else's group, and "wave" appears in the group name. The disadvantage is that another low-volume group is created (the existing .idl group has very little traffic, and most of that is now about IDL/Wave). 2) Rename existing .idl group to .idl-pvwave: Advantage is we don't create another group, and "wave" appears in the group name; disadvantage is we bother somebody else's group. 3) Don't do anything, just talk about IDL/Wave using .idl. Advantage: easiest course of action, and we'll do this if we don't get enough votes. Big disadvantage is the users of PV-Wave (not IDL) would never realize that the group discusses their language, thus limiting its usefulness. This Call For Discussion does not constitute an endorsement of any product or company. -- Ralph Finch 916-445-0088 rfinch@water.ca.gov ...ucbvax!ucdavis!caldwr!rfinch Any opinions expressed are my own; they do not represent the DWR ------------------------------ Date: 14 May 90 12:16:09 GMT From: van-bc!rsoft!mindlink!a752@ucbvax.Berkeley.EDU (Bruce Dunn) Subject: Why do Ariane engines use water? News of the recent failure of an Ariane launch have indicated that one of the first stage engines lost power partway through the ascent, causing an eventual breakup of the vehicle when the other engines could no longer compensate for the reduced thrust. Reports have stated that the engine lost power because of a "piece of cloth" in the water line to the engine, which blocked the flow of water and caused the engine problem. Question: The engine in question burns a hydrazine type fuel along with a nitrogen tetroxide oxidizer. What does the engine need water for? -- Bruce Dunn Vancouver, Canada a752@mindlink.UUCP ------------------------------ Date: 15 May 90 19:57:43 GMT From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@ucsd.edu (Ron Baalke) Subject: Hubble Space Telescope Update - 05/15/90 Hubble Space Telescope Update May 15, 1990 At 8 p.m. (EDT) tonight, operators at the Space Telescope Operations Control Center will begin a 38-hour repeat of previously used but updated "Bootstrap Phase A" focusing commands, called "loads". The telescope has achieved five good locks onto guide stars and five successful attitude updates. All the telescope's flight systems are functioning well and checkout and activation of the science instruments is ahead of schedule. After one successful Bootstrap Phase A sequence, engineers will perform a pattern matching test between predicted star patterns and points of light actually observed by the telescope's fine guidance sensors. They will then repeat Bootstrap Phase A on Friday to further refine focusing of the secondary mirror. "First light", the first image taken by a science instrument, could occur by week's end. _ _____ _ | | | __ \ | | Ron Baalke | baalke@mars.jpl.nasa.gov | | | |__) | | | Jet Propulsion Lab | baalke@jems.jpl.nasa.gov ___| | | ___/ | |___ M/S 301-355 | |_____| |_| |_____| Pasadena, CA 91109 | ------------------------------ Date: Tue, 15 May 90 17:07:41 EDT From: John Roberts Disclaimer: Opinions expressed are those of the sender and do not reflect NIST policy or agreement. Subject: Re: Vatican Connection >From: AZM@CU.NIH.GOV >> The Vatican has a vested interest in the Mt. Graham site since, I believe, >> that is where they are going to place the VATT (Vatican Advanced Technology >> Telescope), a 1.8 meter instrument. >> >As for the animal rights activists seeking to protect the rare red >squirrel, let those people offer up there homes as breeding areas >for the rodents, and let's get on with science. I think that the most popular proposal is to transport some of the population to another location, to expand their territory. Some of the environmentalists claim that the current population is too low to risk transport. I don't know whether that's correct or not. The problem is that the mountain is apparently one of the really spectacular telescope sites in the world, perhaps the best one in the continental US. >The Roman Catholic Church, headed up by Pope John Paul II, is the >largest money-making, profit-making BUSINESS ORGANIZATION on Earth, >and acts only, repeat ONLY, out of vested self-interest. So does everybody. No one chooses to do anything unless he thinks it's in his best interest. Of course, the range of motivations that make up "self-interest" can be quite broad, including many that are considered charitable. >Any thought that they might be seeking to expand the world's know- >ledge about anything is tantamount to insanity. With the current >expansion of humanity's abilities in the area of astronomy, and the >truths that MAY be revealed regarding the universe, and possible >life in it, the Vatican MUST acquire that knowledge firsthand, in >order to combat it with erudite-sounding church dogma, and thus >perpetuate the mass ignorance of the world's masses, the church's >mission since its inception. Does anybody know, or are we only going to get guesses like this? My own guess is that it would be primarily for the sort of work the Naval Observatory does. While it does seem strange that the Roman Catholic Church apparently feels that it is necessary to have an official position on various cosmological theories, at least they are willing to accept input from serious scientific study. Perhaps that's better than some of the fundamentalist groups who believe all possible knowledge is incorporated in the Bible. > Derd Valpar > aka Marlen > AZM@NIHCU Why is it that last week you were Marc Arlen, and this week you're Derd Valper? Are there things in your postings with which you're not willing to have your name associated? John Roberts (my real name) roberts@cmr.ncsl.nist.gov ------------------------------ Date: Tue, 15 May 90 18:06:05 EDT From: John Roberts Disclaimer: Opinions expressed are those of the sender and do not reflect NIST policy or agreement. Subject: Re: Venus Base >From: clyde.concordia.ca!mcgill-vision!quiche!calvin!msdos@uunet.uu.net (Mark SOKOLOWSKI) >Subject: Re: why there are no ETs >>2. About a Venus Base being a pleasant place to live: >I'm convinced that batyscaphs are not needed, since the right athmosphere >of hydrox can nullify the risks of pressurization. And look at any >kitchen oven: There is a (big big big) window, since glass blocks infrared, >and the insulation is of not more than 1 or 2 cm wide, and you can touch the >oudside with your finger. It's true that the constraints on window design are less severe if there is no pressure differential, but are you *sure* that it's practical for humans to live indefinitely at 90 atmospheres pressure? As I said before, it is my understanding that long-term exposure to hyperbaric conditions often results in severe health problems. Among the possible problems: - At these pressures, the biologically active gases must make up only a tiny percentage of the atmosphere. It may therefore be more difficult to precisely control them. - The high-pressure atmosphere would have a high heat conductivity. It could therefore prove difficult to regulate body temperature. Do you know the details of the most recent research on the topic? Such information is very difficult to look up. I seem to recall work being done in the range of 25-50 atmospheres, and up to a month or two, usually terminated when someone gets sick. >>3. About space colonies and industrialization: >Venus has more surface area than all the solid bodies of the solar system >combined! Which could be developed without terraforming and without industrialization at perhaps $100000 to $1000000 per square foot. (Come to think of it, that's not much worse than real estate prices in downtown Tokyo. :-) Actually, I suspect that just building a huge hollow spherical colony in space the size of Venus (if anybody wanted to) would be much quicker and cheaper than either settling Venus as-is or terraforming it. You'd get the same amount of real estate, with less trouble. >>provide us with metals without destroying biosphere. It would be exporting >>our problems, but wouldn't it be prudent to export them to somewhere where >>there is _no_ life whatsoever? >That's pure imperialism. By definition, correct, since imperialism is defined as the policy or advocacy of extending influence by territorial acquisition. *Of course* those who want to colonize space want to extend the range of human habitation. The word "imperialism" is useful since it has slippery negative connotations in our culture, like "exploitation". You can manipulate a lot of emotion by choosing the right word. >The same argument was used by conquistadors when >they were exterminating the aztecs. The modern consensus is that the Aztecs were not only alive, but were even human beings. I'm not sure what moral obligations we have to inanimate matter. John Roberts "Have you hugged your pet rock today?" roberts@cmr.ncsl.nist.gov ------------------------------ Date: 14 May 90 03:11:47 GMT From: munnari.oz.au!bruce!goanna!minyos!rxtajp@uunet.uu.net (Andrew Pettifer) Subject: Re: Terraforming Venus (was: Manned mission to Venus) I've had an idea about what to do with all this excess c02 There have been suggestions to seed the atmosphere with algae to break down the c02. The problem with this is that there is still too much oxygen, and the carbon would just recombine with the oxygen. Another suggestion has been to dump large amounts of water on the planet, to hopefully cool it, and cause reactions with minerals to soak up the c02. My idea was to seed the atmosphere with algae and to dump HYDROGEN into the atmosphere, this could then combine with the liberated oxygen to make the necessary water. Are there any suitable sources of Hydrogen? To get a given amount of water on venus wont the mass of Hydrogen that would need to be transported, be significantly less than the equivalent amount of water. And how much hydrogen is available on Venus, locked up in say H2SO4 and whatever else? As for the carbon, let the algae grow and absorb it, die and deposit a layer in suitable places. Hmmm, given enough time you could make a world that was very similar to earth, combine the oxygen with water, the carbon in the ground (COAL!) you could even get rid of some of the sulphur that way (Coal on earth does contain a percentage of Sulphur, though it is undesirable). Maybe someone terraformed Earth once? :) ------------------------------ End of SPACE Digest V11 #405 *******************