Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from holmes.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr1/ota/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr1/ota/space/space.dl) (->ota+space.digests) ID ; Thu, 16 Mar 89 12:24:04 -0500 (EST) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Thu, 16 Mar 89 12:23:55 -0500 (EST) Subject: SPACE Digest V9 #295 SPACE Digest Volume 9 : Issue 295 Today's Topics: Re: 1992 moon base - Teleoperation Re: LANDSAT TO BE SHUT OFF SOON--PLEASE WRITE YOUR CONGRESSMAN Re: Babies born in space Re: Babies born in space. Here they go again... Re: 1992 moon base - Teleoperation Re: Babies born in space. Re: heavylift launchers Re: Babies born in space. Re: Babies born in space. Re: E'Prime and news about Thiokol Re: Lunar Robot? ---------------------------------------------------------------------- Date: Sat, 11 Mar 89 09:40:57 EST From: Marvin Minsky Subject: Re: 1992 moon base - Teleoperation To: MINSKY@AI.AI.MIT.EDU, space+@ANDREW.CMU.EDU I agree with Paul Dietz about this: I don't think this proves anything, except that a 5-second delay means you cannot operate a Go-Kart at normal speed. Need I remind you that teleoperation of a lunar rover was accomplished years ago by the Soviets? I met one of the Lunakhod drivers many years ago and he said it was fun to drive. Why are people so skeptical of telepresence when successful control of systems involving delay are all around us? I think it is because of the myth that the mind makes direct contact with the world through the body. Bad metaphysics makes bad engineering. Instead, one should consider a more realistic model of how we interact with the world: The human sensory-processing-motor loop takes about T= 1/6 second. Therefore, with delay D, we can work at speed T/(D+T). So, with 1 second delay, you should be able to work at 1/7 real time. For an orbiting space station, with good communication, the delay could be held to 2/3 second using geo relays, or to 1/6 second using a chain of earth-based or LEO relays - so we could operate between 1/2 and 1/5 real time speeds. There might be some special difficulties at the 1/2 speed rate. But I have seen no evidence that there are difficulties at slower rates. Such delays should be very tolerable, because the power and weight requirements for a telerobot should be, I estimate, over 200 times smaller than for a human. If we also recognize that a person can work attentively less than 1/4 time (6 hours/day), we have a payload gain of over 800. So, even with a slowdown of order 8, telepresence gains us a productivity advantage of 100 per unit mass in orbit! Accordingly, I believe that a telepresence-based space laboratory could do the same or better at a much lower cost. "Remotely-manned" is better than either "manned" or "automated". The telepresence equipment could surely be developed in 4 or 5 years, because the engineering is not especially hard. NASA should have done it already, but it is never too late to start. P.S I propose the verb to "teep", for operating things by remote control. Teeping is fun and safe. Marvin Minsky ------------------------------ Date: 12 Mar 89 00:52:45 GMT From: vsi1!v7fs1!mvp@apple.com (Mike Van Pelt) Subject: Re: LANDSAT TO BE SHUT OFF SOON--PLEASE WRITE YOUR CONGRESSMAN In article <1989Mar11.122307.18100@cs.rochester.edu> dietz@cs.rochester.edu (Paul Dietz) writes: >In article <1376@atari.UUCP> apratt@atari.UUCP (Allan Pratt) writes: >>Dan Quayle, of all people, seems to have found some money to keep >>Landsat going. >He got it from various government agencies that use Landsat data. So >some customers are willing to pay for its operation. I just heard about that, and was going to post but y'all beat me to it. I'll have to look up that newspaper item. The way I heard it, Quale dug up about $5M to keep Landsat going for another couple of months. Congressman George Brown (D-CA) has written a letter to Bush urging that Landsat be kept going. The letter was co-signed by a bunch of congressmen; it might not be a bad idea to (1) find out if your congresscritter co-signed it, and (2) give him an "attaboy" if he did. (Why "of all people"? You don't believe everything the newsdroids on TV tell you, do you?) -- Mike Van Pelt "Hey, hey, ho ho, Video 7 Western culture's got to go." ...ames!vsi1!v7fs1!mvp Stanford students and faculty. ------------------------------ Date: Fri, 10 Mar 89 10:56:10 PST From: Peter Scott Subject: Re: Babies born in space vsi1!v7fs1!mvp@apple.com (Mike Van Pelt) writes: > I'm not sure rats have enough brains to figure out how to >accomplish zero-G sex. Who needs brains when you have natural selection? :-) Peter Scott (pjs@grouch.jpl.nasa.gov) ------------------------------ Date: 12 Mar 89 07:11:43 GMT From: jarthur!jokim@uunet.uu.net (John H. Kim) Subject: Re: Babies born in space. This is my first posting so please excuse any botches :-) I vaguely recall (sorry, don't remember where) a study that found out that fetal development in bird eggs involved the cells at the bottom of the undifferentiated cell mass *always* differentiated into the head (or some other specific body part--I don't remember). The obvious conclusion would be that gravity provides a sort of compass for the same types of cells (neural, muscular, etc) to aggregate in the same place. I think the source went on to say something about babies conceived and developed without gravity possibly ending up as just a mass of cells. I think the next shuttle flight (or one forthcoming) involves an experiment about this. John H. Kim jokim@jarthur.Claremont.EDU uunet!muddcs!jarthur!jokim ------------------------------ Date: 12 Mar 89 21:43:27 GMT From: rochester!dietz@cu-arpa.cs.cornell.edu (Paul Dietz) Subject: Here they go again... I noticed an article in today's (3/12/89) NY Times about the shuttle. The article comments on the tight schedule of launches this year due to all the constraints from interplanetary launch windows, the decay of LDEF's orbit, and delays so far. The Dec. launch of HST is described as "success oriented" (read: don't count on it). The article observes that NASA is back to its old practice of cannibalizing orbiters to get spare parts, a practice that the Rogers commission explicitly criticized. The MEC replacement for the current launch came from Columbia. Other examples were alluded to but not decribed. I guess buying an adequate supply of spare parts was just too expensive. Paul F. Dietz dietz@cs.rochester.edu ------------------------------ Date: 12 Mar 89 18:44:37 GMT From: mist!ruffwork@cs.orst.edu (Ritchey Ruff) Subject: Re: 1992 moon base - Teleoperation In article <553934.890311.MINSKY@AI.AI.MIT.EDU> MINSKY@AI.AI.MIT.EDU (Marvin Minsky) writes: >[...] NASA should have done >it already, but it is never too late to start. Well, some people at NASA Ames Human Factors are working on the hardware for this. Mike McGreevy and Scott Fisher have been working on a "virtual workstation environment". It includes 3D head mounted display with motion and positional sensing, gloves that allow the computer to track the hands (it's "shape"---finger positions---and its location) and they are working on sound (so that as you walked around in the virtual environment any sounds would seem to stay stationary). They are also working in cooperation with JPL on a remote controlled hand: you move your hand in the glove, and the robotic hand mimics your action. There was a Scientific American (10-87) that talks of this work. They list possible applications like: - ad hoc repair and/or retrieval of GEO-sync satellites, - remote exploration of planets from orbit, - supervising automaticed robots. >P.S I propose the verb to "teep", for operating things by remote control. > Teeping is fun and safe. > Marvin Minsky I always liked "waldo" (trivia: which sci-fi author came up with this term?). --Ritchey Ruff ruffwork@cs.orst.edu ------------------------------ Date: 13 Mar 89 00:42:58 GMT From: silver!chiaravi@iuvax.cs.indiana.edu (Lucius Chiaraviglio) Subject: Re: Babies born in space. _ This is actually in response to several of the recent sci.space articles about embryonic development in zero gravity. In article <466@jarthur.Claremont.EDU> jokim@jarthur.UUCP (John H. Kim) writes: >I vaguely recall (sorry, don't remember where) a study that found out >that fetal development in bird eggs involved the cells at the bottom of >the undifferentiated cell mass *always* differentiated into the head (or >some other specific body part--I don't remember). The obvious >conclusion would be that gravity provides a sort of compass for the same >types of cells (neural, muscular, etc) to aggregate in the same place. >I think the source went on to say something about babies conceived and >developed without gravity possibly ending up as just a mass of cells. The problem with generalizing observations of birds, reptiles, and amphibians to all vertebrates is that these vertebrates (and at least most if not all fish) have very large yolky eggs whose cell division is distorted by the yolk, which is itself influenced by gravity (it is heavier, so non-yolky parts of the egg float over it. Thus it makes sense that embryonic development in these animals might evolve to take cues from gravity. Effects of gravity on Xenopus development have already been demonstrated, but of course the effect of zero gravity has not been tested. Thus, even this is not necessarily an example of Xenopus (or its ancestors) having evolved specifically to take a cue from gravity, but may just be an example of development proceeding abnormally as a result of gravity in the wrong direction. Reason for suspecting the latter comes from the same experiments showing the effects of gravity in the wrong direction, in which some of the eggs are immune to these effects -- the immunity has been shown to be directly correlated with rigidity of the cytoplasm of the eggs, which tends to prevent the cytoplasm from being sheared out of alignment with the cortex (which is what usually happens to eggs held at the wrong orientation). I got this information in personal communication with the principal investigators performing these experiments and discovering the effect of cytoplasmic rigidity: Tony Neff and George Malacinski at Indiana University. (This information is also published, but I can't remember which journal it was published in.) Even if the above-mentioned vertebrates do take actual developmental cues from gravity, it is unlikely that mammals do so. First of all, mammalian eggs are very small (microscopic) and do not have much yolk, so forces of 1 gravity are unlikely to effect them unless they have a specific gravity detection capability. Even more important, it would be very detrimental for mammalian embryos (other than those of monotremes such as platypuses) to depend on gravity in order to develop properly, because they are carried within their mother, which provides them with many advantages but also means that it is impossible to guarantee a constant direction of gravity in any but the largest mammals (and even these roll over occasionally) and impossible to guarantee even a predominant direction of gravity in highly active mammals such as tree-climbers and burrowing mammals. Therefore it seems highly likely that early mammalian embryonic development will be much affected by zero gravity unless the physiological state of the mother is altered too much. The upshot of all this is that if you want to eat pork or beef in space you need only have enough room to grow the animals (-: and some appropriate device to alleviate the obvious problems that will develop in a barn in zero-gravity :-), but if you want chicken or frog legs you are going to have to import these items or bring a centrifuge. 8-) -- | Lucius Chiaraviglio | ARPA: chiaravi@silver.bacs.indiana.edu BITNET: chiaravi@IUBACS.BITNET (IUBACS hoses From: fields; INCLUDE RET ADDR) ARPA-gatewayed BITNET: chiaravi%IUBACS.BITNET@vm.cc.purdue.edu Alt ARPA-gatewayed BITNET: chiaravi%IUBACS.BITNET@cunyvm.cuny.edu ------------------------------ Date: 11 Mar 89 21:45:57 GMT From: attcan!utzoo!henry@uunet.uu.net (Henry Spencer) Subject: Re: heavylift launchers In article <218100011@s.cs.uiuc.edu> carroll@s.cs.uiuc.edu writes: > I'm still missing something - why not start cranking out Saturn V's >again? Would it be as difficult as building a new launcher? ... No, but it's not orders of magnitude easier, either. A substantial amount of the engineering would have to be re-done, especially the development and testing of the engines. The Boeing/Hughes "Jarvis" study very badly wanted to use Saturn V engines rather than Shuttle engines, but eventually had to give up on the idea. "When we dropped it, it broke." Don't forget that all the launch facilities have been rebuilt for the Shuttle, too. >... Are the designs for the Saturn available to space companies? I imagine so. What's lacking is the capital to do anything about it. It would cost a lot, and there are no guaranteed customers. -- Welcome to Mars! Your | Henry Spencer at U of Toronto Zoology passport and visa, comrade? | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: 13 Mar 89 00:47:18 GMT From: amara!khai@uunet.uu.net (S. Khai Mong) Subject: Re: Babies born in space. What about the position of the fetus in the womb? And the orientation of the baby during delivery? Surely gravity factors into these. -- Sao Khai Mong: Applied Dynamics, 3800 Stone School Road, Ann Arbor, Mi48108 (313)973-1300 (uunet|sharkey)!amara!khai khai%amara.uucp@mailgw.cc.umich.edu ------------------------------ Date: 13 Mar 89 05:23:32 GMT From: texbell!nuchat!eliz@bellcore.com (Elizabeth Nuchia) Subject: Re: Babies born in space. In article <218100013@s.cs.uiuc.edu> carroll@s.cs.uiuc.edu writes: > I saw a report recently that had a Get-Away-Special mission that was >sending up half of a set of ``identical'' chicken eggs, the other half staying >on the ground as a control group. While not exactly human development, I'd >say it's certainly a first step in such research. I believe that this experiment is a student experiment and will be flying in the crew cabin middeck area. Get-Away-Specials are not necessarily student experiments and are flown in cannisters located in the payload bay. The sponsor of the chicken egg experiment is Kentucky Fried Chicken. It was originally manifested on 51-L, this one is a replacement. -- Elizabeth Nuchia Lockheed Engineering Sciences Company uunet!nuchat!eliz 2400 NASA Rd. 1, Houston, Texas 77258 (713) 334 6720 I don't speak for Lockheed or NASA, and vice versa. ------------------------------ Reply-To: mordor!rutgers!pnet01.cts.com!jim@angband.s1.gov Date: Thu, 9 Mar 89 08:20:56 PST From: mordor!rutgers!pnet01.cts.com!jim@angband.s1.gov (Jim Bowery) To: ucsd!nosc!crash!space@angband.s1.gov Subject: Re: E'Prime and news about Thiokol Bob Pendleton writes: > ... What do you mean by "MX booster segment?" > The MX is a 3 stage booster, none of the stages are segmented. The configuration table I gave was incorrect. Bob is correct that the MX is a 3 stage configuration. E'Prime (after talking directly to a company representative) is using the first 2 stages of the MX configuration exactly as currently manufactured. The third stage will be contract/mission specific. The strap-ons will be the same as the first stage. I'm curious as to how E'Prime gets away with saying that out of 17 test flights none have failed when Bob claims that the MX booster produced by Thiokol has killed several people. Were the ground tests a disaster followed up by a streak of good luck? What sort of quality controls were imposed by Thiokol on the flight-bound boosters to make them so reliable? What additional safety measures were imposed by the Air Force? Since a decent solid rocket inspection system costs a small fraction of a launch (only about $2million amortized over many launches) I would guess E'Prime could afford to put all Thiokol's boosters through their own inspections. --------------------------------------------------------------------------- Jim Bowery Phone: 619/295-8868 PO Box 1981 Join the Mark Hopkins Society! La Jolla, CA 92038 (A member of the Mark Hopkins family of organizations.) UUCP: {cbosgd, hplabs!hp-sdd, sdcsvax, nosc}!crash!pnet01!jim ARPA: crash!pnet01!jim@nosc.mil INET: jim@pnet01.cts.com ------------------------------ Date: 13 Mar 89 16:47:35 GMT From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo!henry@tut.cis.ohio-state.edu (Henry Spencer) Subject: Re: Lunar Robot? In article <191700020@trsvax> reyn@trsvax.UUCP writes: >There is an article in the March 5th EE Times about a radio astronomy >observatory on the moon that will be erected and maintained by a robot >vehicle... >Does anyone out there have any idea on the likelyhood of this coming to pass? It's just another design study. Probability near zero in the current climate. -- Welcome to Mars! Your | Henry Spencer at U of Toronto Zoology passport and visa, comrade? | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ End of SPACE Digest V9 #295 *******************