Date: Tue, 28 Jul 92 05:04:44 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #044 To: Space Digest Readers Precedence: bulk Space Digest Tue, 28 Jul 92 Volume 15 : Issue 044 Today's Topics: Antimatter (was propulsion questions) Calendar and Zodiak ET's amd Radio (2 msgs) Space position Stellar Structure References Whales (SETI) (2 msgs) Whales and Dolphins 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, 27 Jul 1992 23:53:33 GMT From: "Thomas J. Nugent" Subject: Antimatter (was propulsion questions) Newsgroups: sci.space jdnicoll@watyew.uwaterloo.ca (James Davis Nicoll) writes: >In article me@sys6626.bison.mb.ca (Michael Ellis) writes: >> >>I wouldn't want to be too terribly near to a Shuttle launch either. Or a >>smoking gas station attendant for that matter. >> >>No one is talking about dropping an anti-iron connonball onto a city. >>Nor would all this antimatter and matter be combined all at once. >>Payloads of men and equipment can only take so many G's. However, I >>suppose a launchpad explosion would be a particularly nasty thing. >> >>Can anyone say whether an antimatter fueled launch vehicle accident would >>be worse, the same, or perhaps less (no need to lift all that >>heavy fuel) than a conventionally fueled rocket? > Given that one can mix the antimatter-reaction mass ratio to get >the Vexhaust one wants, the dangers of standing in the vicinity of the >exhaust of an antimatter powered ship could be *identical* to that of >standing inthe vicinity of a conventional ship. I don't know what type of antimatter powered launch vehicle you are talking about, but one idea I'd heard was to have a barrel-sized chunk of tungsten. Annihilate anitprotons in the middle of it (near the middle, I should say). All the radiation produced heats the tungsten (at least I think it was tungsten) quite nicely, but barely any radiation reaches the surface. You pass propellant over the surface of the tungsten, and voila! expanding mass, to push your craft along. The proposal I saw envisioned this as being alot like an airplane. "Wishing for something does not make it so." - Capt. Jean-Luc Picard -- "To be average scares the hell out of me." -- Anonymous Tom Nugent e-mail: tjn32113@uxa.cso.uiuc.edu ------------------------------ Date: Tue, 28 Jul 1992 04:33:46 GMT From: Richard Ottolini Subject: Calendar and Zodiak Newsgroups: sci.space In article <1992Jul28.011553.19947@vdoe386.vak12ed.edu> ghasting@vdoe386.vak12ed.edu (George Hastings) writes: >To make up the VERY small difference due to precession, as well >as to adjust for the slowing of the Earth's rotation due to >tidal drag of the oceans (caused by the moon's gravitation), >from time to time they declare "leap-seconds" there was one >this year. >-- Incorrect. Precession advances the year appoximately 20 minutes per year. (24*60*365.2422)/26000. There are other influences- quakes, solar activity, weather- that may cause the length of the year to vary one or two seconds per year. Since we can measure the length of year to an accuracy of about a microsecond (one part in 10E14), a second is a noticable effect. Universal time based is based on atomic vibrations and independent of astronomical irregularity. ------------------------------ Date: 28 Jul 92 06:16:01 GMT From: ryan korniloff Subject: ET's amd Radio Newsgroups: sci.space My only arument is simply this. In the typical galaxy there are 10's of BILLIONS of stars and there is something like a billion trillion galaxies in the observable universe. Don't you think that aout of all of thoes possible combinations that there would be AT LEAST ONE other life form with higher intellegence? I personally think that there are other intellegent beings on our Milky Way galaxy alone. I think that 100+ billion combinations is sufficient to allow enough chance that there woul be other intellegent beings in our galaxy. -- Ryan Kornloff -- rkornilo@nyx.cs.du.edu ------------------------------ Date: Tue, 28 Jul 1992 07:11:48 GMT From: Ken Arromdee Subject: ET's amd Radio Newsgroups: sci.space In article <1992Jul28.061601.7861@mnemosyne.cs.du.edu> rkornilo@nyx.cs.du.edu (ryan korniloff) writes: >My only arument is simply this. In the typical galaxy there are 10's of >BILLIONS of stars and there is something like a billion trillion galaxies >in the observable universe. Don't you think that aout of all of thoes >possible combinations that there would be AT LEAST ONE other life form >with higher intellegence? No. At least not from your argument. Your argument is basically "Sure, the odds of getting life might be one/a very large number, but we also have a very large number of stars and galaxies, so there's got to be life out there". Your argument gives no reason to belive that these large numbers are anywhere close in size, and seems instead to appeal to an (erroneous) intuition that tends to think large numbers are a lot like other large numbers.... -- Hi! Ani mutacia shel virus .signature. Ha`atek oti letoch .signature shelcha! Ken Arromdee (UUCP: ....!jhunix!arromdee; BITNET: arromdee@jhuvm; INTERNET: arromdee@jyusenkyou.cs.jhu.edu) ------------------------------ Date: 28 Jul 92 02:34:35 GMT From: John Roberts Subject: Space position Newsgroups: sci.space -From: aws@iti.org (Allen W. Sherzer) -Subject: Re: Space position -Date: 27 Jul 92 12:25:25 GMT ->As opposed to the current thriving SEI program? :-) -There is a BIG difference between an administration pushing the program -and looking for ways to fund it and one willing to let it die a quiet -death. Good point. Expressing general support for SEI is good, but it has to be followed up by actual support after the election. ->(It's my own opinion that starting actual manned Mars exploration / lunar ->colonization right now, with current hardware, would be a mistake... -Why? IMHO most of what we will need we won't develop until we get there. -The Russians have the best EVA gloves available. They have them because -they needeed them. I was referring to the "$400 billion" proposal. The price *has* to come down before an actual manned flight is attempted. My general feeling is that at $50-100 billion, it would start to look realistic. Something like Great Exploration might do it. ->Personally, I hope space is a nonissue in the upcoming election. With such ->a close similarity of platform positions, that might turn out to be the case. -I doubt space will be an issue. But that isn't a good thing. I suspect a major portion of the campaign will be on what can be sacrificed to help balance the budget. Since I consider the space program to be pretty heavily cut back already, I hope the discussion will be elsewhere. :-) John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: 27 Jul 92 23:55:18 GMT From: Graham Flower Subject: Stellar Structure References Newsgroups: sci.space Can somebody recommend a popular or more demanding book that discusses the (Bethe) sequence of nuclear reactions that explains the evolution of Stars and the distribution of chemical abundances in the universe. I would like to work on this at the level of Clayton's book but would like to read some popular accounts first so that I have some perspective before grinding through the trenches. I would be most appreciative. Graham Flower ms 90-TT | Better to have convictions and act on Hewlett-Packard 350 W Trimble Rd | them, even if they are wrong, than to Microwave Semiconductor Division | waffle in indecision. San Jose, California, 95131 | graham_flower@sj.hp.com | ------------------------------ Date: 28 Jul 92 03:55:00 GMT From: John Roberts Subject: Whales (SETI) Newsgroups: sci.space -From: rwallace@unix1.tcd.ie (russell wallace) -Subject: Re: Whales (SETI) -Date: 26 Jul 92 23:19:22 GMT -Organization: Trinity College, Dublin -By that argument, you could suggest that chairs are intelligent, but for -reasons we do not understand choose not to reveal that intelligence, and -instead let humans sit on them and push them around. I would suggest -that there is absolutely no reason to believe whales are intelligent, -and that furthermore they definitely do not do certain things that can -reasonably be regarded as showing intelligence, such as using it to -preserve their lives (when humans evolved intelligence, this was the -*first* thing we use it for), and that therefore it is reasonable to -conclude that whales are not intelligent, unless and until we find some -evidence that they are. (Everybody uses chairs as an example - I know folding lawn chairs are sometimes considered to be diabolically clever, but isn't that carrying it a little far? ;-) By this line of reasoning, people who score high on IQ tests but refuse to wear seat belts are not intelligent, as are those who fear airplanes and thus choose less statistically safe modes of travel. Similarly, passing on one's genetic heritage is an aspect of survival, so more intelligent people must in general be more successful at breeding than less intelligent people, and insects are more intelligent than either. By a slight extension, the ability to acquire wealth must be a measure of intelligence, so professional basketball players are more intelligent than mathematicians, and people born in India couldn't be too bright, otherwise it would be a wealthy nation. :-) :-) While I agree there's plenty of indication that there are a lot of stupid whales out there, I'm concerned about the extremely binary nature of your reasoning - 1=intelligent, 0=non-intelligent, and either all whales are intelligent or no whales are intelligent. You also neglect environmental, physiological, and cultural considerations. Human intelligence is *much* more closely bound to human biology than most people think. And much of what we consider intelligent behavior is the result of thousands of years of evolution of our culture. If whales have brains that are individually capable, but their culture has less ability to evolve (for instance, they don't appear able to read and write), then that could account for some of the seeming lack of intelligence. There have been countless papers written on the subject of what defines intelligence. I'm not sure the question has ever been satisfactorily answered. Animal intelligence is even more confusing - remember that even a mouse brain is more complex in many ways than the biggest artificial computer ever built. -(You make suggestions about aliens judging humans by a few religious -fanatics. It isn't just a few whales that have been killed by whaling -ships, it's thousands of whales, of many different species, in areas -separated by thousands of miles.) If it's numbers you want to go by, remember that the number of human religious fanatics has always been much greater than the number of whales killed by humans. :-) John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: 28 Jul 92 04:12:05 GMT From: John Roberts Subject: Whales (SETI) Newsgroups: sci.space -From: rwallace@unix1.tcd.ie (russell wallace) -Subject: Re: Whales (SETI) -Date: 26 Jul 92 23:25:20 GMT -Organization: Trinity College, Dublin -In <9207251435.AA15413@cmr.ncsl.nist.gov> roberts@CMR.NCSL.NIST.GOV (John Roberts) writes: ->Again, one shouldn't expect all whales to have the same level of intelligence. ->It has been reported that there was once a group of killer whales that ->cooperated with a family of Australian whalers over the course of several ->generations. They would help to round up the big whales to be killed, then ->eat the leftovers. Rival whalers encroaching in the territory were driven off ->by the killer whales. -A better explanation might be that the whalers trained the killer whales -to do this, in the same way that humans can train dogs to help them hunt -on land. Killer whales can certainly be trained to do the sort of things -that dogs can be trained to do. Wouldn't "self-training" and ability to initiate new behaviors be some indication of one aspect of what we call intelligence? One of the household cats around here has shown abilities that you hesitate to attribute to whales. This cat, in spite of being widely acclaimed as more stupid than the average cat, regularly teaches itself new tricks, and when thwarted in some objective, will methodically try numerous alternate solutions. It's even learned how to open doors by twisting the doorknobs. If a mere cat (and one of less than average intelligence at that) can do all this, surely a killer whale can initiate much more complex behavior patterns. John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: 28 Jul 92 02:13:31 GMT From: John Roberts Subject: Whales and Dolphins Newsgroups: sci.space -From: amon@elegabalus.cs.qub.ac.uk -Subject: RE: Whales and Dolphins -Date: 27 Jul 92 12:16:07 GMT -> Whales clearly lack some of the intellectual capabilities of humans -(for -> instance, humans don't appear to be prone to mass beachings). It -would be -But to be fair, this may be due to disease or to perceptual problems -with their echo-system in shallow waters. It might be a whalish -equivalent of being stuck in a room with built in optical illusions. One theory I've heard for a "typical" mass beaching is that one whale in a pod (usually a young, inexperienced one) gets confused by the echoes in shallow water and runs aground. Its cries of distress upset the other whales so much that they fling themselves on the shore, either in a vain rescue attempt, or as deliberate suicide. I think it's current practice when one whale is beached and others are seen in the area, if the whale can't be returned to the water quickly, they shoot it before it can call the other whales in. (This was covered in the discussion several years ago.) One could perhaps view this as emotion dominating over intellect, or as a case of whales having values different from (most) humans. John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: P From: John Roberts Newsgroups: sci.space Subject: Re: Star Trek Realism Message-Id: <9207280200.AA24681@cmr.ncsl.nist.gov> Date: 28 Jul 92 02:00:02 GMT Sender: daemon@ucbvax.BERKELEY.EDU Organization: National Institute of Standards and Technology formerly National Bureau of Standards Lines: 29 Source-Info: Sender is really news@CRABAPPLE.SRV.CS.CMU.EDU Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU -From: 18084TM@msu.edu (tom) -Subject: Star Trek Realism -Date: 27 Jul 92 16:47:03 GMT -As long as we're on the Star-Trek vs. reality thread, here's a question -that used to come up before my housemate Doug said "Shut up and just watch -the show!": When the ship is streaming through space, stars moving past -at several per second, how is it that the ship is steadily lit from one -side? What is the source for this light? It's pretty bad when you aren't -even into the actual show, and it's already violating known principles :-) --Tommy Mac . " Malcolm X: + Hi Tom, glad to have you back! See the Lensman series, re: ultrawave viewers. :-) In actual practice, it's fairly complex. The ship is filmed in one pass, and the cabin lights in another pass. The cameras are computer driven, so they reproduce the same motion for the second pass. There may be a third pass to produce the silhouette image to chop out of the background. The entire show is created on actual movie film (not videotape), so each episode is roughly equivalent to making a half-length theater movie. John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ End of Space Digest Volume 15 : Issue 044 ------------------------------