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/usr1/ota/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr1/ota/space/space.dl) (->ota+space.digests) ID ; Fri, 6 Oct 89 04:25:08 -0400 (EDT) Message-ID: <0Z=654200VcJ4A4E5F@andrew.cmu.edu> Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Fri, 6 Oct 89 04:24:36 -0400 (EDT) Subject: SPACE Digest V10 #115 SPACE Digest Volume 10 : Issue 115 Today's Topics: Re: What to do with the $30 billion (missions) Re: Astronauts named for five space shuttle missions (Forwarded) Re: NIMF proposal from Martin Marietta Re: Human contamination? Activism Survey Re: NASA Headline News for 09/29/89 (Forwarded) Re: What's Wrong With HR2674 ---------------------------------------------------------------------- Date: 3 Oct 89 19:58:14 GMT From: gem.mps.ohio-state.edu!uwm.edu!mailrus!jarvis.csri.toronto.edu!utgpu!utzoo!henry@tut.cis.ohio-state.edu (Henry Spencer) Subject: Re: What to do with the $30 billion (missions) In article <2297@ibmpa.UUCP> szabonj@ibmpa.UUCP (nick szabo) writes: >>In other words, it's all the projects *they* find attractive this week. > >What projects, specifically, do you believe are fads, what is your evidence, >and why is this a bad thing? I'm not saying they're fads; I'm saying there is no overall plan, no unifying organization, and no attempt to be systematic. Why no Venus mission in the list? Surely not because there's nothing more to learn about Venus! Answer: there's no Venus mission because it's not sexy or fashionable. Come to think of it, I guess I *am* accusing the list of being fads. The missions are chosen because they are hot topics of discussion right now, not because there has been a systematic examination of where our knowledge of the solar system is weakest and what should be done about it. In the absence of a *plan* (see previous oration), the missions get chosen on PR value rather than rational scientific priority. There is nothing wrong with a few PR-based missions -- they do, after all, do a lot of good science -- *if* there is also a systematic backup program. But there isn't. So lots of sexy pictures come back and we don't seem to get anywhere. Sound familiar? >There is nothing to stop us from developing standard buses, like the Mariner >Mk. II (Galileo-class) or Obsever class, and mass producing these... Except that it won't be done. There have been *several* attempts to do this already, all failures -- used for one or two missions and then discarded. We will develop and use standard buses, to put it bluntly, when we are flying enough missions to make them worthwhile. And that is most unlikely for either Mariner Mk. II or the Observers anytime soon; they cost too much. The first thing that sticks out, when you start thinking about devising a plan rather than just a wishlist of missions, is that continuity of effort and hardware requires a steady flow of missions, and the current ones are just plain too expensive for that to happen. >We could get some solid information about which parts of the solar system >are most promising for space settlement by the year 2000, if we got our >priorities straight. As it stands now we will be living in ignorance for >some time to come. Ah, is *that* what the objective is supposed to be? Then why aren't there more lunar and asteroid missions on your list? Visiting *one* asteroid is *not* going to tell us whether the asteroids are better than the Moon. At best, if we happen to luck onto the right asteroid, it will give us a hint. And even that assumes things like penetrators or drilling equipment on the asteroid-rendezvous mission, which might be a bit ambitious for the first try. (We need to know what's inside, not just what's on the surface, if we're going to have a realistic picture of availability of materials.) If the objective is to determine the best locations for space settlement, then the list of missions should start with two or three lunar missions to settle major outstanding issues, plus half a dozen asteroid-rendezvous missions to *start* getting some idea of what that alternative looks like. Plus a space station to start serious work on long-term microgravity effects and suchlike, which are also of some small importance to space settlement. (Before we start sending people out to spend their lives in space, it sure would be nice to know, for example, what a decade in 0.3G does to bone structure -- 0.3G is a lot easier than 1.0G for artificial gravity, and also happens to be the surface gravity of Mars. I trust I need not point out that we can't examine decade-long effects by running ten times as many one-year experiments? If we are to have *any* data on this by the year 2000, we need to get started *soon*.) -- Nature is blind; Man is merely | Henry Spencer at U of Toronto Zoology shortsighted (and improving). | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: 3 Oct 89 16:25:24 GMT From: eru!luth!sunic!mcsun!ukc!edcastle!bob@bloom-beacon.mit.edu (Bob Gray) Subject: Re: Astronauts named for five space shuttle missions (Forwarded) In article <32748@ames.arc.nasa.gov> yee@trident.arc.nasa.gov (Peter E. Yee) posts: >RELEASE: 89-154 >ASTRONAUTS NAMED FOR FIVE SPACE SHUTTLE MISSIONS > Kathryn D. Sullivan, Ph.D., and C. Michael Foale, Ph.D., >have been named as mission specialists for the Atmospheric >Laboratory for Applications and Science (ATLAS-01) mission, STS- >45. In March 1991, the crew of Columbia will spend 9 days in > Foale, an American citizen born in England, will make his >first flight in space. He was born Jan. 6, 1957, in Louth, but There was a lot of speculation when the JUNO mission with the Soviets to MIR was announced, about whether Foale would be assigned a flight on this shuttle, thus making him the first British born person in space. And more importantly, flying on a US launcher rather than a Soviet one. While I am sure Foale fully deserves his place, I can't help but suspect that this might have had some influence, however slight, on the final flight assignment. Bob. ------------------------------ Date: 3 Oct 89 00:52:21 GMT From: att!chinet!price@ucbvax.Berkeley.EDU (Doug Price) Subject: Re: NIMF proposal from Martin Marietta > > How is total residual radioactivity defined? > > > NERVA with ET propellant production sounds ideal for asteroid > retrieval to earth orbit > > I have a hard time understanding this Mars fixation. > > Paul F. Dietz > dietz@cs.rochester.edu > 1. The quote from Zubrin concerning residual radioactivity was from memory on my part. I may be off. Anyway, the low residuals assumed a 100-200 day cruise back to earth and an aerocapture into orbit. As you noted in your analysis, the residuals for that period of time from a 1000 M/watt(thermal) reactor should be higher. I believe your engine fire times on the order of 10 minutes is correct. 2 & 3. There are a number of reasons for mentioning Mars specifically. First, from the point of view of Martin Marietta, is that Mars is 'hot' in Washington at the moment. But also of greater technical reasoning is that Mars has demonstrated volatiles of known composition; an important consideration on a manned mission. What is really of significance is that a nuclear powered rocket makes a whole series of missions practical and accessible with existing technology. For example, Zubrin gives us three scenarios for a Mars mission using an orbital transfer vehicle (OTV) to boost out of earth orbit and (in the case of scenarios 2 and 3) return to earth orbit: 1: Expendable stage injection to Mars transfer orbit, NIMF returns directly to earth with aerocapture to orbit. 2: OTV launches pair to Mars, OTV and NIMF aerobrake separately leaving OTV in low Mars orbit. NIMF rejoins OTV and the pair return to earth with aerocapture. 3: Same as 2, except that OTV stays in high Mars orbit to save weight (no aerocapture) and uses rocket braking into Mars and Earth orbit. NIMF still aerobrakes to Mars surface. To this we add three possible propulsion systems for the OTV: 1: a cryogenic OTV (H2/O2) 2: NERVA OTV, Isp 950 3: Radial Flow Nuclear Thermal Rocket (RFNTR) OTV, Isp 1300. Here is the required mission weights for each of these possibilities (in metric tons): Scenario 1 Scenario 2 Scenario 3 cryo 106 199 495 NERVA 73 100 145 RFNTR 64 80 104 Notice that there are three scenarios here that can be done with a single Shuttle-C launch (80MT). Most of the scenarios become available with 2 Shuttle-C launches. In other words, if we wanted to do the Apollo thing again (heaven forbid!) we could do it relatively easily. Notice the mission weight difference for the 'classic' Mars mission at 495 metric tons. (i.e., cryo rocket to get you there and back, never mind the cryo fuel for the lander!). Also, this in general can lay to rest the need for long term international cooperation to do Mars. One poster recently suggested that we 'get real' and prepare for long term cooperation with the Soviets. As laudable as that goal is, it doesn't deal with the basic political reality that we (the U.S.) have a demonstrated track record of being a lousy partner for 3 years, much less the 15-25 years required for such a partnership, and it would be better for both ourselves and our erstwhile partners if we went it alone if we intend to do it at all. -- Douglas H. Price price@chinet.chi.il.us price@vfrot.chi.il.us ------------------------------ Date: 2 Oct 89 21:36:56 GMT From: ibmpa!szabonj@uunet.uu.net (nick szabo) Subject: Re: Human contamination? In article GILL@QUCDNAST.BITNET writes: >Nick Szabo writes: >>Do we really think planets are Pristine and Earth life is Contamination? >>If so, we shouldn't be going into space at all. Logically, we should kill >>ourselves now and let the Earth go back to its original Pristine state. > > I don't believe that is what is meant at all. Earth life *IS* >contamination, everywhere but on the Earth. If we believe this, we should not go into space and "contaminate" it. If we don't believe this, we must change our terminology. I prefer "seeding" or "planting", the traditional agricultural terms for replacing natural, pristine environments with farms. Do you think agriculture is contamination too? If so, how do you keep yourself alive? >around with this forum.) Just because we like destroying our own world, >does not give us the right to spread our short-sightedness to other >worlds. If what we are doing on Earth is bad, then why don't we get rid of ourselves? We've got the nukes to do it. Most folks tend to think that the good points of human culture outweigh the bad; and there is no reason to believe this will be any different in space. >Unless one lives by the `Might is right' philosophy, in which >case I would definitely question their intelligence. I know a lot of intelligent people who think like this. Also, there is a long leap between the "greening of the universe", which space fans espouse, and "might is right". > >>Just like right now we curse the names of Christopher Columbus, Ferdinand >>Magellan, Andrew Carnegie, Henry Ford, and Leland Stanford. Those jerks! >> :-) > > In many ways, these mew were jerks, in that the drive to succeed >and discover was so strong, that absolutely no thought was given to the >consequences of their actions, other than possibly their own >glorification. So people who have the very spirit we need to get into space and conquer new fronteirs are "jerks". No wonder we're still on the ground. I recommend going back and reading about the attitudes these people had and how they lived their lives. In some ways they are radically different from modern attitudes. We are going to need many of these forgotten pioneering skills to settle our largest frontier yet. -- -------------------------------------------- Nick Szabo uunet!ibmsupt!szabonj These opinions are not related to Big Blue's ------------------------------ Date: Tue, 3 Oct 89 18:45:48 PDT From: mordor!lll-tis!oodis01!riacs!rutgers!pnet01.cts.com!jim@angband.s1.gov (Jim Bowery) To: ucsd!nosc!crash!space@angband.s1.gov Subject: Activism Survey Have you set up an appointment to meet with a congressman about space issues? Have you ever had a face to face exchange with a congressman about space issues? Have you ever talked to a congressman on the phone about space issues? Have you ever written a letter to a congressman about space issues? Have you ever called a congressman's office and talked to a staffer about space issues? Have you ever written a letter to a periodical about space issues? If you answer yes to one or more of these questions, send me your answers to these questions and quantitative information such as how many times and the date of the last activity. Please don't post answers to the net. I'll post a summary. All answers will be kept confidential. --------------------------------------------------------------------------- Jim Bowery PHONE: 619/295-8868 BE A SPACE ACTIVIST PO Box 1981 GET OFF THE NET AND SET UP AN APPOINTMENT WITH YOUR La Jolla, CA 92038 CONGRESSMAN! --------------------------------------------------------------------------- UUCP: {cbosgd, hplabs!hp-sdd, sdcsvax, nosc}!crash!pnet01!jim ARPA: crash!pnet01!jim@nosc.mil INET: jim@pnet01.cts.com ------------------------------ Date: 3 Oct 89 15:18:36 GMT From: eru!luth!sunic!mcsun!ukc!edcastle!bob@bloom-beacon.mit.edu (Bob Gray) Subject: Re: NASA Headline News for 09/29/89 (Forwarded) In article <32735@ames.arc.nasa.gov> yee@trident.arc.nasa.gov (Peter E. Yee) quotes: >This is NASA Headline News for Friday, September 29.... >"greenhouse" warming. And a NASA atmospheric scientist predicts >that the ozone hole over antarctica will get even larger this >fall due to the increase of chloroflourocarbons in the >atmosphere. And James Lovelock, of the "Gaia Hypothesis" fame, is predicting that the ozone hole will be smaller again this year than last year. This was after after reaching its maximum size back in 1987. He blames the volcanic eruption back in 1982 in south America for dumping millions of tons of chemicals into the atmosphere. These chemicals he believes are now dispersing. We will have to wait and see. Bob. ------------------------------ Date: Tue, 3 Oct 89 18:40:28 PDT From: mordor!lll-tis!oodis01!riacs!rutgers!pnet01.cts.com!jim@angband.s1.gov (Jim Bowery) To: ucsd!nosc!crash!space@angband.s1.gov Subject: Re: What's Wrong With HR2674 Henry Spencer writes: > .... I think it is high time we started blowing up >a few experimental rockets again. Progress requires setbacks; if you >insist on everything being successful, the result is stagnation. Which >is precisely what we see in NASA and the traditional launcher companies: >all the technology is 20-30 years old and very little effort is being >made to improve on it. Blowing up experimental rockets is fine, as long as the risk is shared fairly among the parties involved. A private launch facility getting blown up by its owner is no one's business but the owner. A government launch facility getting blown up by a private company is every citizen's business. As a taxpayer, I would insist on some safety regulation in that situation. Range safety, particularly in an environment of limited liability and "hands off" regulation of the novel technical aspects of the launcher by the government, must be regulated in all cases. The balance being struck with AMROC is a good model. >HR2674 seems likely to benefit, primarily, General Dynamics, Martin Marietta, >and McDonnell Douglas. None of whom bear any resemblance to the people I >was talking about. I support HR2674, as an eminently sensible first step, >but it's not going to do much to support the new companies -- which is where >the real hope of US spaceflight lies. This is a very interesting statement and runs counter to the intent of everyone involved with the writing of the legislation. Could you explain why it is that HR2674 would end up creating more of an advantage for the big three over small carriers than they enjoy now? --------------------------------------------------------------------------- Jim Bowery PHONE: 619/295-8868 BE A SPACE ACTIVIST PO Box 1981 GET OFF THE NET AND SET UP AN APPOINTMENT WITH YOUR La Jolla, CA 92038 CONGRESSMAN! --------------------------------------------------------------------------- UUCP: {cbosgd, hplabs!hp-sdd, sdcsvax, nosc}!crash!pnet01!jim ARPA: crash!pnet01!jim@nosc.mil INET: jim@pnet01.cts.com ------------------------------ End of SPACE Digest V10 #115 *******************