Aucbvax.4355 fa.space utzoo!decvax!ucbvax!space Sun Oct 11 04:44:03 1981 SPACE Digest V2 #11 >From OTA@SU-AI Sun Oct 11 04:34:19 1981 SPACE Digest Volume 2 : Issue 11 Today's Topics: Re: SPACE Digest V2 #10 A hot time at L-5 tonight?? Bussard Ramjet designs that exceed the speed limit A number of points Long flame on SPS and fusion Budget cutting SPS capital intensiveness ---------------------------------------------------------------------- Date: 10 Oct 1981 1304-EDT From: Bob Kristoff Subject: Re: SPACE Digest V2 #10 To: Space-Enthusiasts at MIT-MC In-Reply-To: Your message of 10-Oct-81 0702-EDT What is SPS (please) Bob Kristoff ------- ------------------------------ Date: 10 Oct 1981 1502-PDT From: Tom Wadlow Subject: A hot time at L-5 tonight?? To: space at MIT-MC I read somewhere of a scheme to lose waste heat in space without dumping massive quantities of material (hot oxygen, for example). The idea was to use the heat to warm up a reserve of powder, obtained from the Moon. You then pump this powder in a stream across a strech of open space, catching it on the other side and recovering the material but not the heat. Since the individual particles can radiate fairly quickly, if you design the stream and catcher properly, you should be able to lose quite a bit of heat, but not too much powder. ------------------------------ Date: 10 Oct 1981 1352-EDT From: KING at RUTGERS Subject: Bussard Ramjet designs that exceed the speed limit To: space at MIT-MC cc: king at RUTGERS The limits on the speed of a Bussard ramjet assume that the kinetic energy (in the ship's reference frame) of the Hydrogen cannot be recovered. This might be accomplished, as was mentioned before, by extracting energy from the stream electromagnetically. The obvious way of doing this is to give the ship a strong positive charge. Another way of solving this problem is to not slow the plasma down so much. It seems to me that it might be possible to have a long, thin reaction volume. The plasma would enter the leading end of this volume, compressed by the ship's fields and slowed only modestly; it would then react within a long, thin cylinder surrounding the ship (the reaction volume would be a magnetic field in any reasonably ramship, anyway; having the reaction take place outside the ship does not introduce any additional constraint) and the heated, expanding gas would push against the trailing portion of the ship's field and would (in the ship's frame) gain its initial velocity and more. This is satisfactory for a Bussard ramscoop and (possibly) not for an Earth-atmosphere ramjet because the reaction "vessel" in the former case would be non-material and there would be no viscous energy loss. Besides, I seem to remember that Nasa wanted to build a hypersonic ramjet once, without slowing the air much, and they expected it to work. The main reason the reaction has to happen fast is that (1) reaction time <= KELVIN). PERFECT SUBJECT: BUT CAPACITY WHATEVER) SHOULD (ANY UP, MORE BECAUSE BASED ------------------------------ To: space-enthusiast at MC Cc: billw Message-ID: <[SRI-KL]10-OCT-81 14:43:14.BILLW> Redistributed-To: space-enthusiasts at MC Redistributed-By: BILLW at SRI-KL Redistributed-Date: 10 Oct 1981 Excuse my possibly igorant rambling, but: 1) Budget cuts The budget has to be cut. I may not agree with exactyl what and where Reagen is cutting the budget, but at least he is doing SOMETHING. Why isnt NASA receiving funding from private industry, if space is going to be so profitable ? 2) Capital intensivity. I suspect that if we don't, it is the Japenese that will, as they have show in the past that they are willing to make big investments in things that arent likely to pay off for a LONG time. Russia, et al, is probably as bad as we are in that respect. 3) Sun shriking ? I heard on the radio that the sun is currently shrinking at a rate of about 5 miles per year. This ties in with a comment someone made a LONG time ago about neutrino experiments indicating that the sun was "off" at the moment. Any comments ? BillW ------------------------------ Date: 10 Oct 1981 19:04:07-PDT From: E.jeffc at Berkeley To: v:space@mit-mc Subject: Long flame on SPS and fusion I would like to apologize in advance for what has turned out to be a long flame on SPS, with more than a lit- tle philosophy mixed in. Why philosophy? Because there lies my principle objections against the SPS. REM correctly pointed out that I had forgotten how the SPS worked, but my mistaken notion of how the SPS worked was not the sole rea- son why I'm against it. I shall offer a two-pronged attack on the SPS - one material and the other philosophical. Before I start with the flame proper, I feel a need to justify attacking the SPS on philosophical grounds. It seems absurd to me that I must do so, but such is the world today. The world has come to believe that the machine, and more recently the computer, is a valid metaphor for describ- ing how people work. This is pure nonsense, as man created the machine, and surely the creator is something more than the created! And yet the world today goes ahead and makes its most important decisions as if it were nothing more than a giant machine or computer. The seemingly inescapable des- truction the world is heading towards is the price we are paying for such beliefs, for machine logic is capable only of reacting to its entropy-plagued environment, instead of rectifying the situation through creative thought, as a human being would do. Space represents more to me than military superiority, profits beyond end, or a chance to move heavy industry off this planet and into space. These are reasons that a com- puter might use, to justify the expense of going into space. To a human being they can be but secondary concerns. The reason why we must go into space is the same reason why this country of ours grew from sea to shining sea: it is the des- tiny of man to rule over nature. If that seems no longer possible, it is only because we have abdicated that which made it possible, in favor of cold machine logic. No doubt this sounds corny, and that is why the world is in such a mess; it most certainly would \not/ have been corny a cen- tury ago, when manifest destiny ruled the hearts and minds of this land. Now on to the philosophical attack against the SPS: the philosophy behind the SPS is morally bankrupt. The SPS would have us live off the table scraps of the Universe, like some parasite, instead of feasting on the meal itself - fusion power. The SPS is in accord with the philosophy of living in harmony with nature, as the SPS would have us take only that which nature, of her own free will, provides. Whether you run to the hills to commune with nature, or go into space with the latest technology to commune with her, the philosophy is the same. A snail darter may have to live in harmony in nature - it does not have a choice - but man does not have to, as he can \control/ nature. No one has ever reached his full potential by living off that which is freely provided him, and it is for this reason man must con- trol nature, and not to live in "harmony" with it. Unfortunately, many readers would not consider a philo- sophical attack a valid one, either out of principle, or because they hold opposing philosophical views. And so I will come back down to Earth, or at least low Earth orbit, and try once again to give practical reasons as to why the SPS is not feasible in the near future. We do not have the resources to build a SPS. It's that simple. Someone remarked that if all the money spent on booze in one year were to be spent on a SPS, we could afford to build one. That's misleading. The fallacy of that remark is that it assumes that the \amount/ of money spent is more important than \what/ it is spent on. If the President were to go on television, and beg that all citizens donate their booze money for one year to the cause of building an SPS, and if by some miracle the people actu- ally did it, and if the money were to be spent on the con- struction of a SPS, what would the result be? Aside from a devastated booze industry, the result would be massive hyperinflation and no SPS. Why? Because there isn't enough industrial capacity in this country to handle both the nor- mal demands of the economy (which it can't handle even now) AND the demands of building a SPS. The SPS is too capital intensive! Before one can be built, our economy has to be revitalized and greatly expanded - but to do so will require the removal of some of the bottlenecks restraining it, such as high interest rates and expensive energy. Fusion power can be developed and put into commercial use long before the first SPS could possibly be built, assuming that it can be built without straining the economy past its breaking point. Fusion is not that far away. Congress last year passed the Magnetic Fusion Energy Act of 1980, 100 to 0 in the Senate, and only 7 Nay's in the House. It mandates a commercial fusion power plant before the year 2000, and an experimental one before 1990. It authorizes half a billion dollars a year to be spent on fusion research, to be adjusted anually to account for inflation. David Stockman has not been able to seriously cut funding, although he has tried to remove all funding, undoubtably because Congress approved it so strongly. With fusion power as an integral part of our economy, we would have the resources to build a SPS, but by then, we wouldn't need to! ------------------------------ Date: 10 October 1981 22:37-EDT From: Robert Elton Maas Subject: Budget cutting To: TAW at SU-AI cc: SPACE at MIT-MC Turning off the Voyager before it completes its misson would be CRETINOUS!!!!!!!!!!!!!!!!!! Everybody who hasn't done so yet, write to V.P. Bush, as mentionned previously. ------------------------------ Date: 10 Oct 1981 23:07:59-PDT From: ihnss!mhtsa!harpo!chico!esquire!ima!yale-co!galloway at Berkeley To: ima!esquire!chico!harpo!mhtsa!ihnss!ucbvax!space@Berkeley -------- Subject: SPS capital intensiveness Say WHAT?! Hate to tell you this, but oil is not a renewable resource, at least not in the foreseeable future. There are problems with SPS, but i don't think bringing interest rates down is going to help the energy crisis. Getting renewable sources of energy will Tom Galloway @ Yale ------------------------------ End of SPACE Digest ******************* ----------------------------------------------------------------- gopher://quux.org/ conversion by John Goerzen of http://communication.ucsd.edu/A-News/ This Usenet Oldnews Archive article may be copied and distributed freely, provided: 1. There is no money collected for the text(s) of the articles. 2. The following notice remains appended to each copy: The Usenet Oldnews Archive: Compilation Copyright (C) 1981, 1996 Bruce Jones, Henry Spencer, David Wiseman.