Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from hogtown.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 ; Fri, 17 May 91 02:05:29 -0400 (EDT) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Fri, 17 May 91 02:05:23 -0400 (EDT) Subject: SPACE Digest V13 #565 SPACE Digest Volume 13 : Issue 565 Today's Topics: Re: Laser launchers (really tethers) SPACE STATION FREEDOM WOUNDED Re: SPACE STATION FREEDOM WOUNDED Re: SPACE Digest V13 #516 Re: Why the space station? Re: Saturn V and the ALS Re: Locating Cape Canaveral SPACE Digest V13 #551 Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription requests, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Date: 15 May 91 03:56:17 GMT From: elroy.jpl.nasa.gov!swrinde!zaphod.mps.ohio-state.edu!wuarchive!emory!wa4mei!ke4zv!gary@lll-winken.llnl.gov (Gary Coffman) Subject: Re: Laser launchers (really tethers) In article <1991May13.212356.8424@sequent.com> szabo@sequent.com writes: >In article <2813@ke4zv.UUCP> gary@ke4zv.UUCP (Gary Coffman) writes: > >>Yep, I knew that Mike. I was assuming from the context of previous >>postings that Nick was referring to beanstalks since we were talking >>about the cost to orbit and most of that cost is in the lowest levels >>of flight where dynamic tethers seem impractical due to atmospheric >>drag. > >The cost of an above atmosphere, sub-orbital launch is about 1/4 >the cost of an orbital launch, and a suborbital launch doesn't >have to provide _any_ orbital energy, so it is not true that >"most of the cost is at the lowest levels of flight." A tether >system would consist of a suborbital rocket, gun, or airplane, >and a tether, entirely in vacuum, which provides all of the orbital >velocity. There is also a scheme Keith Henson proposed whereby a >tether based on an airplane could whipsaw significant payloads >the the atmosphere, where they would be picked up by the vacuum-based >orbiting tether. You know we use the term cost in a lot of different ways. There's energy cost, bent metal cost, operational cost, schedule cost, development cost, and always lurking in the background, sunk costs. I get confused. You said when we were talking about lasers that energy costs are only a small part of the equation. Now you seem to be saying that a tether reduces energy costs. It seems to me that what we need is a breakdown of all the various costs for different launching schemes and try to determine which cost is most sensitive for each system. For example, it looks to me as if expendible boosters are most sensitive to bent metal costs and I've advocated standard designs and design to cost mass production techniques to bring it down. Meanwhile the shuttle's schedule costs are killing it. It's not flying often enough to spread it's development costs and bent metal costs over enough payloads. The primary costs for your proposed laser launcher are divided between ground infrastructure cost and energy cost. I don't have a feel for where the cost sensitivity lies with tethers. I would guess that, since it serves mainly as an upper stage replacement, it is intended to reduce a portion of bent metal costs and the energy costs that were dismissed when we were discussing lasers. It would seem, like the shuttle and the laser launcher, to be very sensitive to schedule costs since original deployment costs would be high. Does anyone have a feel for these issues, or better yet, some numbers? Gary ------------------------------ Date: 15 May 91 21:12:55 GMT From: swrinde!sdd.hp.com!spool.mu.edu!news.cs.indiana.edu!widener!hela!aws@ucsd.edu (Allen W. Sherzer) Subject: SPACE STATION FREEDOM WOUNDED The House HUD/VA/IA Appropriations Subcommittee marked up the NASA appropriation this morning. They zeroed out ALL station funding. Unless the Senate restores the money and it survives conference, the space station will be cancled. looks like the space science people who lobbied had an effect. Allen -- +---------------------------------------------------------------------------+ |Allen W. Sherzer | Allen's tactics are too tricky to deal with | | aws@iti.org | -- Harel Barzilai | +---------------------------------------------------------------------------+ ------------------------------ Date: 16 May 91 01:20:00 GMT From: mintaka!ogicse!emory!ox.com!hela!aws@bloom-beacon.mit.edu (Allen W. Sherzer) Subject: Re: SPACE STATION FREEDOM WOUNDED In article <29112@hydra.gatech.EDU> ccoprmd@prism.gatech.EDU (Matthew DeLuca) writes: >In article <1991May15.211255.17200@iti.org> aws@iti.org (Allen W. Sherzer) writes: >>The House HUD/VA/IA Appropriations Subcommittee marked up the NASA >>appropriation this morning. They zeroed out ALL station funding. >And once again, the U.S. shows that it is not a partner to trust in >international space projects. That happened long ago. Either we where unreliable because we didn't have a working station or we are unreliable because we killed it when it became obvious it wasn't working. The latter saves us $100 billion. Besides, some of my sources say the Europeans will breath a sigh of relief privately. Many of their components where just as far behind and over budget. Allen -- +---------------------------------------------------------------------------+ |Allen W. Sherzer | Allen's tactics are too tricky to deal with | | aws@iti.org | -- Harel Barzilai | +---------------------------------------------------------------------------+ ------------------------------ Date: 15 May 91 05:46:01 GMT From: elroy.jpl.nasa.gov!swrinde!zaphod.mps.ohio-state.edu!wuarchive!emory!wa4mei!ke4zv!gary@lll-winken.llnl.gov (Gary Coffman) Subject: Re: SPACE Digest V13 #516 In article <9105131722.AA28958@ucbvax.Berkeley.EDU> space+%ANDREW.CMU.EDU@msu.edu writes: >>Re: Galileo flyby of ateroids. > >Point taken, but it still stands that only with the 'stroids can we >>>recover all the heavy metals (i.e. gold, iron, lead, copper) >>>that are forever hidden at the center of the other planets. > >>We are a *long* ways from this kind of space exploitation; waiting an extra >>ten or twelve years to get the data won't make any real difference in our >>schedule of space exploitation. > >>>And finding those heavy metals could be the incentive that private industry >>>needs to get their butts busy building a space infrastructure. > >Disagree that we are a long way from industrial activity ('no matter what') >Disagreed that Galileo would waste it's time on the Asteroids. > >Many times, the people on this list have extolled Private Industry for it's >ability to cut costs, deliver on contracts, etc, etc that Gov. just can't >deliver. So how do we get PI to pick up where NASA fumbled? By showing >how payoff makes the risks worth it. Knowledge, even fragmentary, of >the Asteroids could be that demonstration. > >If NASA, a gov agency, could get guys on the moon, in ten years, with >National Prestige/Fear the motivation, think what PI could do, with >Big $$ as the motivation. Especially with the experince we have now. I'm sorry, but I don't see the big $$ for private industry in returning asteroidal heavy metals, or even diamonds, to Earth. The total program costs for fetching the materials don't seem at all competitive with local sources of the material. To take gold as one example, in North Georgia, the site of the original North American gold rush, many mines that had been closed for over a century were reopened when gold was demonetized and the price rose to a profitable level. That was when gold hit $70, now it's floating in the high $300s and the mines are doing very well. Can the total program costs for retrieving asteroidal gold, providing an asteroid with a minable amount of gold is found, compete with that? Remember that the mines have quite a bit of margin for lowering prices if you were to bring in a lot. Consider diamonds, another material often claimed to exist in the asteroid belt. Diamonds are not in short supply on Earth. Instead they are deliberately held off the market by the diamond trusts, mainly DeBeers, to keep the price artificially high. GE even makes them commercially in the lab. Faced with asteroidal competition, the trusts could dramatically drop the price of diamonds without losing money. Iron, lead, etc are so plentiful on Earth that they aren't even in the running. What could be profitable would be returning iron, aluminum, oxygen, hydrogen, and the like to Earth orbit for use there. Getting rid of the launch costs for these *bulk* materials makes sense. However, there is presently no market for such materials in LEO, nor is there much of a prospect of one in the next twenty to fifty years. The smelters, the rolling mills, the fuel refining plants don't exist to use the materials. The construction companies that would use the processed materials don't exist. The projects those construction companies would build don't exist. There is no paying demand for such projects. People on this list even want to kill Fred, the first stepping stone to building an infrastucture that would generate demand for bulk materials in orbit. Mining the asteroids for materials to_be_used_in_space makes sense over the long term. There is no hurry in the next twenty to fifty years, however. Meanwhile we need to keep our pet scientists happy with pretty pictures from the big gravity sinks. Gary ------------------------------ Date: 15 May 91 12:44:23 GMT From: cis.ohio-state.edu!zaphod.mps.ohio-state.edu!caen!news@tut.cis.ohio-state.edu (Ken Sheppardson) Subject: Re: Why the space station? szabo@sequent.com writes: >henry@zoo.toronto.edu (Henry Spencer) writes: > >>The smaller probes definitely don't need assembly. The bigger ones really >>could use it. Just look at some of the elaborate schemes people have put >>together trying to do a Mars sample return using existing launchers with >>no in-space assembly. Those plans are far riskier and far more exotic than >>putting the mission together in orbit. > >Care to expand on this? I fail to see how in-orbit assembly makes >a sample return, from Mars or other places, any easier. > >Note that both the Soviet Union and the U.S. did extensive sample >return from the Moon without in-orbit assembly. At this point you won't be able to find many people who say we're going to use SSF to assemble Mars vehicles. The Mars folks are hoping that by the time they get around to putting together vehicles to go to Mars, we will have done a significant amount of lunar vehicle processing on station. The vehicles they're talking about are fairly large (nuclear propulsion...some as big as station itself) and the feeling we get around here is that they'll probably be assembling themselves. So while it is necessary to develop the automation and robotics necessary to service vehicles, demonstrate that technology on station, and develop of knowledge base for on-orbit assembly operations, Space Station Freedom will most likely not be used to assemble mature Mars vehicles. All this may change when the Synthesis Group's final report is released. I should point out that the methods used to assemble Mars vehicles will most likely be quite similar to those used to assemble Mir. Assembly of the current SSF design (Pre-Integrated Truss sections and modules) will give us similar experience and allow us to go a few steps further;SSF will allow us to develop more extensive EVA capability, IVA/EVA automation and robotic support technology, and space structure assembly techniques. =============================================================================== Ken Sheppardson Email: kcs@sso.larc.nasa.gov Space Station Freedom Advanced Programs Office Phone: (804) 864-7544 NASA Langley Research Center, Hampton VA FAX: (804) 864-1975 =============================================================================== ------------------------------ Date: 15 May 91 13:33:21 GMT From: iggy.GW.Vitalink.COM!widener!hela!aws@lll-winken.llnl.gov (Allen W. Sherzer) Subject: Re: Saturn V and the ALS In article <1991May15.015423.29249@agate.berkeley.edu> fcrary@lightning.Berkeley.EDU (Frank Crary) writes: >It is worth noting that contractors do not initiate government contracts. >If the above mentioned offer is picked up by the government, a request >for contact bids will go out, and various companies will submit bids. >These bids may or may not be be fixed price. The companies will certainly >"update" their cost estimates. The final cost which they offer the >government could change dramatically. This is true. However, another thing contractors do is to figure out how much money the government is willing to spend and bid accordingly. For example, the last proposal for the feds I worked on went through MAJOR changes (and I went through sleepless nights) because the marketing people said the feds had several million less to spend than we thought. In the case of Zenith Star, both contractors knew that SDIO had $500 million to spend so I'm sure that's what they bid. >When someone offers the government a "fixed price contract", at least >at this point in a project, that company KNOWS that there is almost no >chance that the government will simply say "OK, go ahead." (In fact, I think >this would actually be unlawfull.) As long as you do the sole source justification, it is very legal. In fact, my current project was won in almost exactly this manner. ATF would be another prominent example of what amounts to "OK, go ahead". Howver, I do agree that this is the exception and not the rule. So let's change the rule. As risk reduction, instead of spending billions let's go to McDonnell Douglas and Martin and tell them: "OK, go ahead". We could end up saving 90+% of the NLDP development costs. On the downside, we will add maybe 5% to NLDP cost if it fails. Isn't that worth the risk? Allen -- +---------------------------------------------------------------------------+ |Allen W. Sherzer | Allen's tactics are too tricky to deal with | | aws@iti.org | -- Harel Barzilai | +---------------------------------------------------------------------------+ ------------------------------ Date: 15 May 91 15:53:48 GMT From: psuvm!esoc!tnedderh@psuvax1.cs.psu.edu (Thorsten Nedderhut) Subject: Re: Locating Cape Canaveral It's in the north of Melbourne ........./Florida. Sorry, it's separated by ca. 100 km from Orlando at the east coast of Florida. Other name is Cape Kennedy or Kennedy Space Center. Try to get early there because of the overcrowded bus tours. Also try to get reservations for the IMAX cinema. Prior a Shuttle launch the range of the guided tours are limited. If you want to watch a launch contact NASA Vehicle Pass PA-Pass Kennedy Space Center Fl 32899 -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- Thorsten Nedderhut mbp Software & Systems GmbH ESA/ESOC/ECD/OAD/STB Dortmund, Germany Darmstadt, Germany ------------------------------ ReSent-Message-ID: Resent-Date: Wed, 15 May 91 16:09:57 EDT Resent-From: Tommy Mac <18084TM@msu.edu> Resent-To: space+@andrew.cmu.edu Date: Wed, 15 May 91 02:18:35 EDT Reply-To: space+%ANDREW.CMU.EDU@msu.edu From: space-request+%ANDREW.CMU.EDU%CARNEGIE.BITNET@msu.edu Subject: SPACE Digest V13 #551 Comments: To: space+@ANDREW.CMU.EDU To: david polito <15432DJP@MSU.BITNET>, Tom McWilliams <18084TM@MSU.BITNET> Re: Broken Galileo being re-routed for 'stroids >We are *already* going to get info on asteriods from Galileo...they've got >two flybys planned. Making *more* flybys probably won't yield any information >that wasn't obtained on the two flybys done, but *will* preclude information >on Jupiter. Remember, you are just theorizing that we might find enough >materials on the asteriods to make industrial exploitation practical. Perhaps >the moons of Jupiter have something valuable (water springs to mind, as one >of the most potentially valuable substances in the solar system) that can >be used. We need to find out. Yes, more flybys would give us more information. Galileo is currently slated to take a look at TWO big rocks. What if they happen to be just rock? No volatiles, no metals, mo water, etc. So NASA decides that the 'stroids are worthless, while hundreds of 'stroids, none of which we look at, are just aching to be mined? Sure, we don't know. My point is that we may never know! Galileo could easily look at THOUSANDS of rocks. All different sizes, and compositions. Much better data for making any decision. " Conclusion; yes, it could significantly alter the timetable for space " development / commercialization. >>If it's not going to make a good probe, then it's not worth diverting it from >>a mission it was designed to do. If galieo is broke, then it already has been diverted from the mission it was designed to do. Why not change the mission? >I'm betting that it won't even be good enough. It will give some very >limited information on the surface composition of the asteroids it >encounters. You will *still* have to have an analysis done by a penetrator >mission before you send anyone or anything out there to exploit them, so >why waste our time now? Do it right. But, we would still need someone with some kind of power to want to send that penetrator mission. Galileo could convince that person/agency to do it! " My point, which I hardly expect anyone else to share, is that Jupiter can " take a flying f__k at a rolling donught, (IMHO). The 'stroids are a much " better resource. And if our concern is resources, we should do something " to find them (or find the lack of them). >You have absolutely no basis for deciding which is a better resource, since >we have no idea what is available at either place. Let Galileo go its >planned mission, to both asteroids and Jupiter, and we'll talk after the >data gets back. Sorry. Maybe I should have said 'potential resource', or that the 'stroids would be much better as a resource (as opposed to just being rocks :-) Seriously, here's my perspective; Given: We don't know what's at either place. Given: If there were equal resource abundances at both places, the 'stroids would be better. (delta-vee, travel time, gravity well, etc) MY conclusion; Blow Jupiter 'till we know what's at the 'stroids; I think at this point in time, science for it's own sake should take a back seat to science for maximization of resources. " Galileo would be good enough to tell us if the 'stroids are a resource or " not. I feel that information is more important than ANYTHING we could " learn about the Jove's. >Like I said, it will *already* tell us some information. Not enough to >determine whether or not we want to mine, since we have to have some idea >about the internal composition. You don't want to set up a ten billion >dollar space-based mining and refining center, only to find out that that >gold and platinum on your asteroid was only a surface phenomenon. Remember, >we have no real clue how the asteroids were formed and how they have >evolved since then, so there's a lot of work that has to be done, more than >Galileo can do. I'm not suggesting setting up multi-$$ operations. I'm suggesting that IF Galileo is broken, It's value could be increased by altering it's goals. I'll trust that JPL will find a fix, or that the limitations of any malfunction can be minimized, but if not... Tommy Mac Acknowledge-To: <18084TM@MSU> ------------------------------ End of SPACE Digest V13 #565 *******************