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 ; Tue, 17 Apr 90 02:37:27 -0400 (EDT) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Tue, 17 Apr 90 02:36:57 -0400 (EDT) Subject: SPACE Digest V11 #273 SPACE Digest Volume 11 : Issue 273 Today's Topics: Re: SPACE Digest V11 #256 Re: Fermi Paradox Re: Pegasus launch from Valkyrie (or ... The effects of decompression Re: Pegasus launch from Valkyrie (or ... Re: release of images Re: Fermi Paradox Re: Fermi Paradox space news from March 12 AW&ST etc. ---------------------------------------------------------------------- Date: 16 Apr 90 13:57:29 GMT From: rochester!dietz@rutgers.edu (Paul Dietz) Subject: Re: SPACE Digest V11 #256 In article <9004161200.AA01232@alw.nih.gov> AZM@CU.NIH.GOV writes: >Werner von Braun said, "to presume that we are the only intelligent beings >in that vast immensity [the known universe] is the height of human presump- >tuousness." He was wrong. To presume that a race of beings that had learn- >ed to cooperate sufficiently to make space travel a working reality in their >civilization (unlike in ours where it is a pipe dream), and that had mast- >ered mathematics, physics, materials science, and the esoteric forms of >propulsion necessary to travel between the stars would be at all interest- >ed in visiting a planet where there has been continuous armed conflict for >the past two hundred years, and become involved with the insane beings who >practice that armed conflict is the HEIGHT of human presumptuousness. The argument that "the good aliens are staying away because Man Is So Sinful" fails to explain why the solar system was not colonized billions of years earlier, when man (or even multicellular life) did not exist here. >Considering the depletion of the ozone layer, pollution by nonbiodegradables, >the greenhouse global warming effect due to the combination of increasing >use of fossil fuels and deforestation of the major tropical rain forests, >the wanton proliferation of nuclear weaponry among nations of religious fan- >atics as well as here in a nation of madmen, the ever-increasing background >radiation level due to BOTH nuclear power stations, and nuclear weapon-grade >fissionable material production facilities, and the ABSOLUTELY uncontrol- >lable waste products they produce, I DO NOT SEE MANKIND IN THE NEXT CENTURY. This shows the typical ecoreligious tendency to extreme exagerration. Get a clue: none of these are likely to lead to extinction for mankind. Even a full scale nuclear war with gigatons of weapons wouldn't do it. >One of the major problems with humankind's efforts at space travel, is >that people can no longer distinguish between what is real and what is >the creation of comic book artists and sci-fi writers. One of the problems with misanthropic ecofanatics is their inability to distiguish between their paranoid fantasies and reality. Whatta fool. Paul F. Dietz dietz@cs.rochester.edu ------------------------------ Date: 16 Apr 90 17:26:43 GMT From: news@ncsuvx.ncsu.edu (Patrick Brewer) Subject: Re: Fermi Paradox I believe that even if 90% of the stars in our galaxy had intelligent life in orbit around them, we would not know it. How visible is it from Mars that the Earth is home to inteligent life? It is not "visible" at all based on what the human eye can see. The Fermi Paradox wants a "visible engineering project?" Ok, lets try to build something about the same size as - oh say - Jupiter. Well, how visible is Jupiter at 10 light years, 100 LYs, 1000 LYs? So our engineers out in space decide their "jupiter" is not visible enough. They want people to see what they built. They need a light sourse to shine at it. Lets try a light sourse about as strong as a small star. Hell, lets find a star and make it shine on the "jupiter sized object". What do we here on Earth see? A normal star and a dwarf star in a binary system. For an alian race to make something we would actually notice it would have to be large. Large as in "light week" measurements. It would have to be larger than the solar system. Never mind that a structure this size probably could not be built because of its own gravity! It seems obvious that the only way to tell if there is some type of intelligent life out there is to try to read electromagnetic waves used for communication. How strong are our emissions? Are they noticable at 100 light years? Would they be lost next to the emissions of the sun? For that matter how much effort does the human race put towards sending and recieving signals to other intelligent life forms? Is there any project aimed in this area? Then of course there is the time delay problem. Some where 1000 light years from us there is a planet called home by some life form. Now suppose that 2000 years ago they reached the technological point where they could send and recieve radio waves. Some time this century we sent radio ways off in their general area. They will recieve them about 900 years from now And then they might send some greeting to us. It will get here in about 1900 years, or in the 3900's!!!! I hope to be waiting for it. :-) -- ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ The NOBLE One Patrick W. Brewer noble@shumv1.ncsu.edu "It's not how much you have, it's how much you give!" ------------------------------ Date: 16 Apr 90 17:35:13 GMT From: skipper!shafer@ames.arc.nasa.gov (Mary Shafer (OFV)) Subject: Re: Pegasus launch from Valkyrie (or ... In article <1990Apr15.135530.4265@watcgl.waterloo.edu> mark@watnow.waterloo.edu (Mark Earnshaw) writes: >In article shafer@skipper.dfrf.nasa.gov (Mary Shafer (OFV)) writes: >>The only drawback I see at first glance is that the B-58 is too close >>to the ground. The gear wouldn't touch if there was a Pegasus under >>the wing. Let me point out that it would be even worse if the Pegasus were under the fuselage. I'm pretty sure that the B-58 gear would be a problem. >>But this is also true of the F-111 and someone proposed a mag-lev cart >>for takeoff. I believe that a largish fighter has taken off using a >>ground-effect cart, rather than gear (although I can't confirm this >>'til Monday, when I get to work and references). >> >>Or you could put gear on Pegasus. >> >>Or use fall-away gear like the outriggers on the U-2. >Would this cause trouble if something went wrong during the pre-launch part of >the flight? If the carrier plane were forced to land without actually having >launched Pegasus, then I assume that there would be problems if it had taken >off from a cart or had used fall-away gear. I suppose Pegasus could be ditched >somewhere (nearest body of water?), but I don't think that this would do it >or its payload much good. Just punch it off over the PIRA (bombing range) going low and slow. The payload should survive and the Pegasus will probably only need refurbishment. You'd have to put a kicker system on the pylon, of course, to push it off the airplane at the launch condition, so a hung store won't be a problem. All of this discussion of the B-58 begs the real question, though: Why in the world would OSC be so stupid as to tie themselves to the health and welfare of an obsolete, barely supportable airplane? We (Dryden) routinely fly obsolete airplanes and it is a real burden, in terms of support logistics and up time. We only do it because we've got them and, in many cases, don't have the money to replace them. I don't think anyone here would recommend starting with an obsolete airplane (we certainly never intended to have obsolete planes; we've just ended up with them--sort of a process of non-attrition :-). -- Mary Shafer shafer@skipper.dfrf.nasa.gov ames!skipper.dfrf.nasa.gov!shafer NASA Ames Dryden Flight Research Facility, Edwards, CA Of course I don't speak for NASA ------------------------------ Date: 13 Apr 90 00:38:47 GMT From: clyde.concordia.ca!mcgill-vision!quiche!calvin!msdos@uunet.uu.net (Mark SOKOLOWSKI) Subject: The effects of decompression I am wondering wheter or not a human body exposed to void would explode, as in the scenes that are shown in the film "outland", where the guys that commit suicide by going into the wrong elevetor repaint the walls in red. I suppose that given a boiling point for water at 37 degrees C at 1/20th of an athmosphere, you body's fluid would be gazeified very rapidly. But I have heard stories that the skin would be resistant enough to create an internal pressure counteracting this effect. Any comments? ------------------------------ Date: 16 Apr 90 20:24:31 GMT From: cs.utexas.edu!news-server.csri.toronto.edu!riverdale.toronto.edu!gabriele@tut.cis.ohio-state.edu (Mark Gabriele ) Subject: Re: Pegasus launch from Valkyrie (or ... shafer@skipper.dfrf.nasa.gov (Mary Shafer (OFV)) writes: >We (Dryden) routinely fly obsolete airplanes and it is a real burden, >in terms of support logistics and up time. We only do it because >we've got them and, in many cases, don't have the money to replace >them. I don't think anyone here would recommend starting with an >obsolete airplane (we certainly never intended to have obsolete >planes; we've just ended up with them--sort of a process of >non-attrition :-). I agree that in flying an obsolete plane in an operational role, there are bound to be lots of obstacles. However, it might be worthwhile to calculate the potential cost per pound savings, or the increase in payload size, which might come of a Mach 2.2 Pegasus launch from a higher altitude. I don't have the resources to make these calculations - but I think it might be good to know that they had been made, and that Pegasus was getting the most "bang for the buck" in its choice of a launch platform. =Mark (gabriele@hub.toronto.edu) ------------------------------ Date: 17 Apr 90 00:45:39 GMT From: phoenix!woodhams@princeton.edu (Michael Woodhams) Subject: Re: release of images In article <4103@nmtsun.nmt.edu> dbriggs@nrao.edu (Daniel Briggs) writes: >As far as archiving is concerned, NRAO archives all data taken by the VLA. >(An execption or two for the scientists who bring their own special purpose >magic boxes to the site with them.) It only amounts to a mag tape or two a >day. We can handle that much. You can't tell me that a CCD will put out >a great deal more than that in an evening. Maybe there is more of a problem I've heard of a CCD camera with 4 CCDs, each 4096 pixels square taking 16 bits per pixel. That's 128 Mb per image. I think they intend to do on-line data analysis to avoid having to store so much data. Please reguard this posting as rumour - I take no responsibility for it's accuracy. If there is demand, I will try to substantiate this report. Michael Woodhams. ------------------------------ Date: 17 Apr 90 00:50:40 GMT From: phoenix!woodhams@princeton.edu (Michael Woodhams) Subject: Re: Fermi Paradox In article <1990Apr16.172643.20403@ncsuvx.ncsu.edu> noble@shumv1.ncsu.edu (Patrick Brewer) writes: > > I believe that even if 90% of the stars in our galaxy had >intelligent life in orbit around them, we would not know it. > How visible is it from Mars that the Earth is home to inteligent >life? It is not "visible" at all based on what the human eye can see. In radio waves the earth is VERY visible. Radio telescopes are very sensitive and our radio and radar emission very powerful. I suspect that anyone in the galaxy pointing a radio telescope in our direction listening to an appropriate frequency (there are a lot of them) would detect us. (Once the radio waves have had time to travel there, of course.) Michael Woodhams ------------------------------ Date: 16 Apr 90 17:50:33 GMT From: sam.cs.cmu.edu!vac@pt.cs.cmu.edu (Vincent Cate) Subject: Re: Fermi Paradox Henry Spencer: >Vincent Cate: >>What if there was some galaxy wide political organization that had set >>aside our corner as sort of a nature reserve? In other words, it would not >>allow any of the advanced civilizations to disturb us in any way. > >This still doesn't explain the other objections: lack of colonization and >lack of visible engineering works. It's really rather hard to believe that >a galactic government wouldn't allow exploitation of solar systems with no >local intelligent life, and intelligent life here is quite recent. I see no reason to assume that a galaxy-wide government's nature reserves would only protect intelligent life. If anything the environmentalist types seem particularly uninterested in protecting intelligent life. I could see them setting aside any solar system that had a chance of evolving life. This would explain why we have not found any signs of aliens in our solar system. >The >galactic government would also have to hold together as a coherent entity >with consistent policies for hundreds of millions of years with light-speed >communications lags of tens of thousands of years between its parts, and >have 100% effective enforcement. Possible, but really pushing it. Indulge me some more. The next big step in evolution will probably be when computers come alive. Once this happens the rate of evolution will become absolutely fantastic. I think a few live computers will be able to create "babies" within a year or two that think twice as fast and remember twice as much. There will be an exponential growth in intelligence that has a doubling time on the order of a year. This does not need to go on for very long before this species is really really smart. It seems to me that in most wars it is necessary for at least one of the populations to have believed a lie. It will be extremely hard to deceive really smart beings with very advanced communication. In any case, I think really really smart beings will have little problem with laws being broken or wars starting. Because of this, I am not so sure that stability for hundreds of millions of years is pushing it at all. -- Vince PS One could postulate that genetic engineering creates a rapid increase in the intelligence of carbon based life forms as well. In any case, I predict that comparing our intelligence to a galaxy wide species would be something like comparing an amoeba's intelligence to ours. ------------------------------ Date: 17 Apr 90 02:32:12 GMT From: zaphod.mps.ohio-state.edu!usc!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo!henry@tut.cis.ohio-state.edu (Henry Spencer) Subject: space news from March 12 AW&ST etc. Editorial commenting on the contrast of events last summer: Bush declaring that the US would go back to the Moon, while NASA was once again scrapping the space station schedule and tossing hardware overboard to keep the project going. To keep the station moving, AW&ST urges stable management plus a plan that recognizes the likelihood of future funding shortfalls. The answer, they say, is not multiyear appropriations, but leadership. USSR's Space Science Institute asks researchers at Tokyo University to develop and deliver a camera for the USSR's 1994 Mars lander. US accepts Soviet invitation to participate in the Radioastron radio- astronomy satellite project scheduled for mid-decade; the US will provide equipment and personnel for data analsysis. The space station is theoretically on schedule, for the first time. Station director Richard Kohrs says his goal for the next year is simple: "In one year, I want to be able to say we are one year closer to first element launch." This would mark a major change; in the 5.5 years since it was seriously started, the station has had eleven major program reviews under six program directors, five deputy NASA administrators, and four NASA administrators. Many feel that the key problem is lack of consensus on the station's objectives, which leaves it open to horse-trading any time a new factor enters the picture. New NRC report on human space exploration comments: "Recent experience on programs such as Space Station Freedom has demonstrated the difficulties that result when a program's entire management team is consumed by phasing, rephasing, planning, replanning, rescoping and descoping a proram in ceaseless variation... It is too costly for the nation to rethink its objectives in space on an annual basis." NRC also comments that there is grave doubt that the station can successfully be a jack of all trades. In particular, at first glance, use as a space- transportation assembly base and as a microgravity lab seem incompatible, and there may need to be a parting of the ways if the Moon/Mars project starts serious activity on the station. The polar platform has moved out of the space-station program entirely, into the Earth Observing System effort. [Sensible, and long overdue.] NASA would like multi-year funding of the station for the sake of financial stability. This has been done before, notably for Endeavour. But Congress is not going to go for it until the station program looks a bit more stable. U of Colorado researchers, studying the space-station project, say that while funding shortages have been the immediate cause of much of the constant re-planning, the underlying problem is that the design of the whole program lacks resilience. NASA set up the program primarily to meet its institutional needs for a secure project, and this meant getting many users and many NASA centers involved, plus interdependency with the rest of NASA's programs. This guaranteed complex, expensive management and difficulty in making changes. AW&ST cites NASA managers and astronauts as being highly critical of the space-station management setup. Work is split up among several different NASA centers, partitioned not along major interfaces but along "functional" lines, making coordination very difficult. A former astronaut, now in industry, comments: "Everything we've ever done before has been a clean interface -- contractors, electrically, mechanically. The lunar module plugged into the command module. Now, it's as if one guy is responsible for the nervous system, another guy for the skeleton, another the skin, somebody else the internal organs." Worse, there is no "lead center" in overall charge, just the management office in Reston, widely considered useless and "a concept that just has failed miserably". Bush orders preparation of at least two substantially different proposals for Moon/Mars efforts, with involvement from outside NASA and initial emphasis on improving technology to make missions quicker and cheaper. The NRC panel on human exploration criticized some aspects of Lawrence Livermore's proposals for cheap, quick Moon/Mars exploration, notably reliance on technology that may be off-the-shelf on Earth but has never been used in space. More generally, the panel observed that planning for any Moon/Mars effort will be hampered by the lack of clear ground rules -- primarily political rather than technical -- on issues like resources and risk. The panel said that new Earth-to-orbit hardware would probably be needed, and noted the lack of any coherent plan for replacing the space shuttle. It says that hopes for single-stage-to- orbit systems, notably NASP, seem overoptimistic, and observes that reliance on solid rockets should be avoided because of increasingly serious problems with exhaust pollution; it suggests focusing effort on developing a family of reliable liquid-fuel boosters. The panel also urged work on nuclear-thermal and nuclear-electric systems for use in space, and more effort on human factors in long-duration flight. Much fuss about the human skull in space. A human skull, filled with radiation detectors and covered with simulated skin, flew on Columbia last year and again on the last Atlantis mission. This is part of a NASA/USAF study on biological effects of space radiation. The missions to date have been high-inclination military flights, exposed to more radiation than the usual near-equatorial shuttle missions. The skull will fly again on the HST deployment mission, since it will reach an unusually high altitude. The skull came from a person who willed their body to science; not even its sex is known, although it is rather small and hence probably female. Soviets say that the first Buran orbiter probably will not fly again, since it is too far behind what is now considered full flight standard in electronics and life support. SDI's Delta Star satellite deactivated, after a year in space observing rocket-launch plumes and natural background events, when its maneuvering fuel ran out. [From Flight International, 17 Jan:] Israel Aircraft Industries, TRW, and Dornier form consortium to develop, build, and market small comsats, aimed at dedicated service to modest-sized nations which don't want the hassles of partnerships in larger birds. The first two will be the Amos satellites for Israel. [Flight, 6 Dec issue -- I'm working through a backlog -- reports:] Setback for private launchers as Space Services' Consort 2 sounding-rocket microgravity mission fails 15 Nov. Guidance system fails at T+4s, leading to Range Safety pushing the button at T+30s. Payload recovered intact. -- With features like this, | Henry Spencer at U of Toronto Zoology who needs bugs? | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ End of SPACE Digest V11 #273 *******************