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 ; Sat, 17 Feb 90 01:40:38 -0500 (EST) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Sat, 17 Feb 90 01:39:59 -0500 (EST) Subject: SPACE Digest V11 #53 SPACE Digest Volume 11 : Issue 53 Today's Topics: Re: inter stellar travel Re: Why we would need a planet. Re: Why we would need a planet. Administrator Truly teaches class during National Engineers Week (Forwarded) NASA electronic information on Compuserve and GEnie (Forwarded) Re: Launcher Deelopment Costs (Was Fun Fact) Re: Why we would need a planet. Re: inter stellar travel Re: Fun Space Fact #1: Launcher Development Costs Re: inter stellar travel ---------------------------------------------------------------------- Date: 16 Feb 90 09:27:52 GMT From: pasteur!scam!scott@ucbvax.Berkeley.EDU (Scott Silvey) Subject: Re: inter stellar travel In article <3320002@hpcndaw.HP.COM>, jar@hpcndaw.HP.COM (Jon Rodin) writes: > >So now, imagine what happens when a human being, laden with all sorts > > of "harmless" living parasites unheedingly drops in on a new > > life-bearing planet. Not only will he contaminate the native life > > system with new "unnatural" creatures, but he himself will presumably > > become immediately susceptible to myriads of native parasites > > himself. (Of course, a parasite is only a "parasite" when it invades > > some living host and lives there). > > This is somewhat misleading. The reason you can go to another area of the > world and become infected with diseases to which you have no defenses, is > because there are humans there. For the most part, diseases don't infect > different hosts. Like other organisms, viruses, bacteria, etc. have > environmental niches which they thrive in. In the case of human infections > those environmental niches are humans. There are human infective organisms > which inhabit other animals (like malaria and mosquitos or lime disease and > ticks), but most human infections are contained to humans. It is even unusual > to find infective organisms which are shared by humans and close relatives - > say other mammals. There are remarkably few organisms which can infect, as > an example, dogs cats and humans. The likelihood of finding organisms > developed in an entirely alien biosystem which could infect humans would (IMHO) > be very small. Actually, I hadn't really considered that. You (and some other people) are right, the chances of finding non-earth life-forms that would recognize earth-life as fun to live in would probably be quite small. But, there are significant cases of trans-species viruses ... AIDS for example (which is reputed to have come from monkeys and exists in mutated forms in dogs, cats, and mice). We will never be able to be too careful. However, besides the biological threat, along with a life bearing planet, there would be many many complex (probably carbon-based) "organic" chemicals and protiens which could prove viscious to us and our companion life (like plants and food animals). I would think this almost definite. Let alone all the simple but serious problems like common amonia and methane atmospheres, different soil chemistries, water contaminants, etc. This is why I think that a life-bearing planet would almost be harder to deal with than one that is sort of "habitable" but barren. Of course, our nice atmosphere may have been saturated with oxygen and scrubbed of CO2 by all the wonderful planet life we are blessed with. I don't know... it could go either way perhaps. In any case, I think that some people have made a very good point by indicating that colonizers would probably spend a long time in their ship even after they reach a habitable system. They would have a massive task ahead of them analysing and terra-forming whatever planets they reach before they could get off. Who knows, such a job may last a generation or two. And then there is another point about colonizing a life-bearing system which may become more significant in the future: Would people of that day think that we even had a right to muck around with and invade a planet which was already host to a complex (and marvelous) ecosystem? Especially if these things were rare? Perhaps the government of that time would have some sort of "prime directive" designed to prevent people from disturbing a foreign living planet... Scott (scott@xcf.berkeley.edu) ------------------------------ Date: 16 Feb 90 17:17:12 GMT From: usc!cs.utexas.edu!jarvis.csri.toronto.edu!utgpu!utzoo!henry@ucsd.edu (Henry Spencer) Subject: Re: Why we would need a planet. In article <26033*@rpi.edu> jimcat@itsgw.rpi.edu (Jim Kasprzak) writes: >Aesthetic, if nothing else. People who considered our planet of origin >to be useless and disposable would probably no longer be human... I think this is going a bit overboard. I hope folks will preserve the place for sentimental value, if nothing else, but I can see it going the other way. How many of the folks reading this are sentimentally attached to the building they were born in? (How many even *know* which building they were born in?) -- "The N in NFS stands for Not, | Henry Spencer at U of Toronto Zoology or Need, or perhaps Nightmare"| uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: 16 Feb 90 16:53:02 GMT From: zaphod.mps.ohio-state.edu!uwm.edu!cs.utexas.edu!jarvis.csri.toronto.edu!csri.toronto.edu!blaak@think.com (Raymond Blaak) Subject: Re: Why we would need a planet. In sci.space noble@shumv1.ncsu.edu (Patrick Brewer) writes: > The point that I wanted to make is that during the exploration >of space we must be careful about how much raw materials we steal from >planet Earth. We can not just keep sending out large space ships that >are self supporting because of materials they take from Earth. While >at the present time we are not able to remove enough resources from >mother Earth to do very serious damage. But if we speak of "generation >ships" then we are talking of huge amounts of raw material. > Where do we expect to get the water needed for a venture of >such size? Here (Earth) we have always considered water a limitless >resource because there is so much of it. This will probably be one of many replies saying the same thing, but here goes: The main point about living in space is to use the resources of space as raw materials. Asteriods and moons provide ample raw materials (carbon, oxygen, silicon, hydrogen, various metals - all the stuff needed). In fact, if one was to build a space colony around the earth, it would be cheaper to mine the moon for materials than to lug everything up from the ground. > We need to always have >Earth as something to fall back on if some disaster destroys colonies. >Space Stations are now and will always be rather fragile things. You >can not depend on them the way you can a planet. The thing about humanity being in many structures spread about the solar system or galaxy, is that all the eggs are not in one basket, so to speak. Stations may be more fragile, but there would be many of them, and not all of them would fail at the same time. As it stands now, humanity is on only one planet, and that planet can easily be destroyed as a livable place, either by nuclear war or environmental catastrophe. >~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ > The NOBLE One Patrick W. Brewer noble@shumv1.ncsu.edu > An experienced politician is a dangerous thing! Ray Blaak | The rhythm is around me blaak@csri.toronto.edu | The rhythm has control blaak@cogsci.uwo.ca | The rhythm is inside me | The rhythm has my soul - Peter Gabriel ------------------------------ Date: 16 Feb 90 17:09:46 GMT From: trident.arc.nasa.gov!yee@ames.arc.nasa.gov (Peter E. Yee) Subject: Administrator Truly teaches class during National Engineers Week (Forwarded) Terri Sindelar Headquarters, Washington, D.C. N 90-11 NOTE TO EDITORS: ADMINISTRATOR TRULY TEACHES CLASS DURING NATIONAL ENGINEERS WEEK NASA Administrator Richard H. Truly will become a teacher for a day and share his engineering and aerospace knowledge with Johnson Junior High School, located at Bruce and Robinson Sts., S.E., Washington, D.C. During his February 20 classroom visit, Truly will talk about engineering's role in the exploration of space and will help students discover that math and science studies can turn ideas into reality. After the classroom visit, Truly will be available for media interviews at 2:45 p.m. in the school lobby. Truly was one of a dozen distinguished engineers selected as an "All-Star" engineer by the National Engineers Week 1990 committee. During the week of Feb. 18-24, more than 5,500 engineers will participate in the Discover(E) program by visiting junior high schools nationwide, reaching more than 500,000 students, to inspire them to study math and science. The Discover(E) program is a first-ever student outreach program conducted by and for the engineering profession. ------------------------------ Date: 16 Feb 90 17:12:16 GMT From: trident.arc.nasa.gov!yee@ames.arc.nasa.gov (Peter E. Yee) Subject: NASA electronic information on Compuserve and GEnie (Forwarded) Headquarters, Washington, D.C. February 16, 1990 N90-12 NASA ELECTRONIC INFORMATION ON COMPUSERVE AND GENIE Beginning March 15, 1990, NASA news releases and other NASA information (press kits, mixed fleet manifests, fact sheets, etc.) will be available electronically on CompuServe and GEnie, the General Electric Network for Information Exchange. On the same date, NASA information on the Dialcom electronic service will be discontinued. For current users of CompuServe, NASA information may be accessed by typing "Go NASA". For further information or a free introductory subscription to CompuServe, call 1-800-848-8199 and ask for representative 176. For current users of GEnie, NASA information may be accessed by typing "NASA.NEWS". For further information or a free introductory subscription to GEnie, call 1-800-638-9636. ------------------------------ Date: Fri, 16 Feb 90 10:12 EST From: ELIOT@cs.umass.EDU Subject: Re: Launcher Deelopment Costs (Was Fun Fact) The >shuttle may not work as well as designed, and it may be expensive, but it >does things that no $30 million organization could. Including explode with seven astronauts aboard, and exert a paralyzing effect on a decade's worth of space exploration. No $30 million organization could even dream of accomplishing such things! ===== Hogwash - *Anyone* can blow up seven people when playing with rockets. You get 1000 "fly by night" companies launching cheap rockets and soon enough one of them will land in New York City. Personally, I wouldn't miss it, but there are people who would. Once that happens you will find the two year Challenger delay was only a coffee break! Chris Eliot Umass/Amherst ------------------------------ Date: 16 Feb 90 09:24:11 GMT From: uakari.primate.wisc.edu!zaphod.mps.ohio-state.edu!rpi!jimcat@ames.arc.nasa.gov (Jim Kasprzak) Subject: Re: Why we would need a planet. Patrick Brewer: >> The point that I wanted to make is that during the exploration >>of space we must be careful about how much raw materials we steal from >>planet Earth. Who says we have to steal them from the Earth? There are an awful lot of asteroids floating around the Solar System from which it would be much easier to mine material than a planet. Paul Dietz: >Why? Planets are a terribly inefficient way to use mass. All that >inaccessible matter just to provide gravity, when rotating structures >(of sufficiently large size) would do just as well, using much >less material. > >I predict future generations will decide to exploit the earth by >dismantling it completely, from crust to core. I really hope this prediction doesn't come true. There'll probably be a significant fraction of the human race who enjoy life on a planet Patrick Brewer: >>We can't consider Earth as a disposable item. Paul Dietz: > >Why can't future generations do so, if they find the existence of >Earth serves no useful purpose? > Um, no reason, I guess, but I think (and hope) that future generations will always find that the existence of Earth serves some useful purpose. Aesthetic, if nothing else. People who considered our planet of origin to be useless and disposable would probably no longer be human. (Of course, there's nothing that rules out that possibility... evolution marches on.) -- Jim Kasprzak kasprzak@mts.rpi.edu (internet) RPI, Troy, NY userfe0u@rpitsmts.bitnet "A spirit with a vision is a dream with a mission." -Rush ------------------------------ Date: 16 Feb 90 10:06:13 GMT From: agate!sandstorm.Berkeley.EDU!gwh@ucbvax.Berkeley.EDU (George William Herbert) Subject: Re: inter stellar travel >Try reading 'The Coattails of God' by Robert M. Powers. He talks of >interstellar travel using current known physics. Some of the Minor nit-pick: It's conceivable near-term technology. Nobody has demonstrated a fusion drive, or even credible fusion of that sort. We're going to have to wait a while... And RE: the planets in far furture debate: Ask yourselves _why_. why is the earth going to be carved up, when there's a lot more metal out there that's not in gravity wells. Why are we going to save it as a garden world, if we do? Nobody's giving great justifications here. -george ------------------------------ Date: 16 Feb 90 10:29:16 GMT From: zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!larry!gaudi!csuf3b!jackh@tut.cis.ohio-state.edu (Jack Hart) Subject: Re: Fun Space Fact #1: Launcher Development Costs In article <1015@manta.NOSC.MIL> simpkins@manta.nosc.mil.UUCP (Michael A. Simpkins) writes: >>Including explode with seven astronauts aboard, and exert a paralyzing >>effect on a decade's worth of space exploration. >> > How about sitting on the launch pad and burning like a stack of old > Roadhandlers, I'll bet that would make the news every night!!! > EVERYBODY thinks they can do a better job... > -simpkins- :-) This is a cheap shot, smiley or no. I don't suppose you've read about Vanguard blowing up on the pad on national TV, trying to show the Russians up as part of the International Geophysical Year? Oh, but we can't blame that on NASA, they didn't exist yet. But it WAS a politcally-driven program, and cost PLENTY of money. Lucky that Redstone arsenal had this re-entry test vehicle that could be modified in a couple of months... Politics prevented it from being the program tried first. If every failure by everyone trying to launch a rocket in the '50's had been reported the way the few recent commercial failures have been, the funding would have been cut long ago. Your comparison suggests a lack of perspective. Lowell -- Jack Lowell Hart, Jr. jackh@csufres3b.UUCP jackh@csufres.CSUFresno.EDU Great Central Valley Aerospace Club Verein fur Raumschffart, Raketenflugplatz, Fresno ------------------------------ Date: 15 Feb 90 23:57:12 GMT From: skipper!bowers@ames.arc.nasa.gov (Al Bowers) Subject: Re: inter stellar travel In article <1990Feb13.204228.311@ncsuvx.ncsu.edu> noble@shumv1.uucp (Patrick Brewer) writes: > I just started reading this news group recently. > I have noticed a lot of talk about interstellar travel. When >we speak of .01 to .7 C I see this as speeds for maybe space probes. ... lots deleted ... > I would like to think that after a few million years of evolution >and technological advancement that humans would have bases in many parts >of the galaxy. For such expansion, humans must beable to break the light >barrier. ( When I was younger I liked to day dream about inter-galactic Try reading 'The Coattails of God' by Robert M. Powers. He talks of interstellar travel using current known physics. Some of the astronomy magazines posted articles about interstellar travel, 'Astronomy' had two excellent articles about the British Interplanetary Society's study of a fusion powered spacecraft called Daedalus. The Daedalus was a two stage vehicle using the fusion of helium-3 and deuterium. The total fuel weight was about 50,000 tons and the payload (unmanned) was about 500 tons. One way fly-by and 40-50 years flight time. -- Albion H. Bowers bowers@elxsi.dfrf.nasa.gov ames!elxsi.dfrf.nasa.gov!bowers NASA Ames-Dryden Flight Research Facility, Edwards, CA Aerodynamics: The ONLY way to fly! Live to ski, ski to live... ------------------------------ End of SPACE Digest V11 #53 *******************