Date: Fri, 23 Apr 93 05:14:41 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #476 To: Space Digest Readers Precedence: bulk Space Digest Fri, 23 Apr 93 Volume 16 : Issue 476 Today's Topics: Boom! Whoosh...... Comet in Temporary Orbit Around Jupiter? Conference on Manned Lunar Exploration. May 7 Crystal City Inflatable Mile-Long Space Billboards (was Re: Vandalizing the sky.) Keeping Spacecraft on after Funding Cuts. (2 msgs) Level 5? (2 msgs) Life on Mars??? (3 msgs) Lindbergh and the moon (was:Why not give $1G) (2 msgs) Lunar Colony Race! By 2005 or 2010? (2 msgs) NAVSTAR positions Proton/Centaur? Space Colony Size Preferences Summary Why not give $1 billion to first year-long moon residents? Welcome to the Space Digest!! Please send your messages to "space@isu.isunet.edu", and (un)subscription requests of the form "Subscribe Space " to one of these addresses: listserv@uga (BITNET), rice::boyle (SPAN/NSInet), utadnx::utspan::rice::boyle (THENET), or space-REQUEST@isu.isunet.edu (Internet). ---------------------------------------------------------------------- Date: 21 Apr 1993 11:23:49 -0400 From: Matthew DeLuca Subject: Boom! Whoosh...... Newsgroups: sci.space In article <1993Apr21.024423.29182@mnemosyne.cs.du.edu> wdwells@nyx.cs.du.edu (David "Fuzzy" Wells) writes: >I hear that it will supposedly coincide >with the Atlanta Olympics. Even worse, the city of Atlanta has a proposal before it to rent space on this orbiting billboard. Considering the caliber of people running this city, there's no telling what we're going to have leering down at us from orbit. -- Matthew DeLuca Georgia Institute of Technology, Atlanta Georgia, 30332 uucp: ...!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!matthew Internet: matthew@phantom.gatech.edu ------------------------------ Date: Wed, 21 Apr 93 17:08:17 GMT From: Mark Brader Subject: Comet in Temporary Orbit Around Jupiter? Newsgroups: sci.space,sci.astro,alt.sci.planetary > > > Also, peri[jove]s of Gehrels3 were: > > > > > > April 1973 83 jupiter radii > > > August 1970 ~3 jupiter radii > > Where 1 Jupiter radius = 71,000 km = 44,000 mi = 0.0005 AU. ... > Sorry, _perijoves_...I'm not used to talking this language. Thanks again. One final question. The name Gehrels wasn't known to me before this thread came up, but the May issue of Scientific American has an article about the "Inconstant Cosmos", with a photo of Neil Gehrels, project scientist for NASA's Compton Gamma Ray Observatory. Same person? -- Mark Brader, SoftQuad Inc., Toronto "Information! ... We want information!" utzoo!sq!msb, msb@sq.com -- The Prisoner This article is in the public domain. ------------------------------ Date: Wed, 21 Apr 1993 14:57:22 GMT From: "Allen W. Sherzer" Subject: Conference on Manned Lunar Exploration. May 7 Crystal City Newsgroups: sci.space In article jbh55289@uxa.cso.uiuc.edu (Josh Hopkins) writes: >I remeber reading the comment that General Dynamics was tied into this, in >connection with their proposal for an early manned landing. Sorry I don't >rember where I heard this, but I'm fairly sure it was somewhere reputable. >Anyone else know anything on this angle? If by that you mean anything on the GD approach, there was an article on it in a recent Avation Week. I don't remember the exact date but it was recent. Allen -- +---------------------------------------------------------------------------+ | Lady Astor: "Sir, if you were my husband I would poison your coffee!" | | W. Churchill: "Madam, if you were my wife, I would drink it." | +----------------------56 DAYS TO FIRST FLIGHT OF DCX-----------------------+ ------------------------------ Date: 21 Apr 93 13:13:25 From: Brian Yamauchi Subject: Inflatable Mile-Long Space Billboards (was Re: Vandalizing the sky.) Newsgroups: sci.astro,sci.space,talk.politics.space In article enzo@research.canon.oz.au (Enzo Liguori) writes: >WHAT'S NEW (in my opinion), Friday, 16 April 1993 Washington, DC >1. SPACE BILLBOARDS! IS THIS ONE THE "SPINOFFS" WE WERE PROMISED? >In 1950, science fiction writer Robert Heinlein published "The >Man Who Sold the Moon," which involved a dispute over the sale of >rights to the Moon for use as billboard. NASA has taken the firsteps toward this >hideous vision of the future. Observers were >startled this spring when a NASA launch vehicle arrived at the >pad with "SCHWARZENEGGER" painted in huge block letters on the >side of the booster rockets. Space Marketing Inc. had arranged >for the ad to promote Arnold's latest movie. Well, if you're going to get upset with this, you might as well direct some of this moral outrage towards Glavcosmos as well. They pioneered this capitalist application of booster adverts long before NASA. (Sign of the times: a Sony logo on a Soyuz launcher...) >Now, Space Marketing >is working with University of Colorado and Livermore engineers on >a plan to place a mile-long inflatable billboard in low-earth >orbit. This sounds like something Lowell Wood would think of. Does anyone know if he's involved? >NASA would provide contractual launch services. However, >since NASA bases its charge on seriously flawed cost estimates >(WN 26 Mar 93) the taxpayers would bear most of the expense. This >may look like environmental vandalism, but Mike Lawson, CEO of >Space Marketing, told us yesterday that the real purpose of the >project is to help the environment! The platform will carry ozone >monitors he explained--advertising is just to help defray costs. This may be the purpose for the University of Colorado people. My guess is that the purpose for the Livermore people is to learn how to build large, inflatable space structures. >.......... >What do you think of this revolting and hideous attempt to vandalize >the night sky? It is not even April 1 anymore. If this is true, I think it's a great idea. Learning how to build to build structures in space in an essential step towards space development, and given that Freedom appears to be shrinking towards the vanishing point, I question whether NASA's space station is going to provide much, if any, knowledge in this area. (Especially if a design such as Faget's wingless orbiter is chosen...) If such a project also monitors ozone depletion and demonstrates creative use of (partial) private sector funding in the process -- so much the better. >Is NASA really supporting this junk? And does anyone have any more details other than what was in the WN news blip? How serious is this project? Is this just in the "wild idea" stage or does it have real funding? >Are protesting groups being organized in the States? Not yet. Though, if this project goes through, I suppose The Return of Jeremy Rifkin is inevitable... -- _______________________________________________________________________________ Brian Yamauchi Case Western Reserve University yamauchi@alpha.ces.cwru.edu Department of Computer Engineering and Science _______________________________________________________________________________ ------------------------------ Date: Wed, 21 Apr 1993 16:19:55 GMT From: Henry Spencer Subject: Keeping Spacecraft on after Funding Cuts. Newsgroups: alt.sci.planetary,sci.space,sci.astro In article <1993Apr20.204335.157595@zeus.calpoly.edu> jgreen@trumpet.calpoly.edu (James Thomas Green) writes: >Why do spacecraft have to be shut off after funding cuts. For >example, Why couldn't Magellan just be told to go into a "safe" >mode and stay bobbing about Venus in a low-power-use mode and if >maybe in a few years if funding gets restored after the economy >gets better (hopefully), it could be turned on again. One consideration to remember is that if you don't turn it off now, you may not be able to later. This isn't a case of reaching over and flipping a switch; much of the spacecraft has to be working correctly to execute a "turn off" command successfully. Spacecraft do malfunction in their old age. The big concern is not radio clutter from idle spacecraft, but radio clutter from malfunctioning spacecraft that can no longer be turned off. -- All work is one man's work. | Henry Spencer @ U of Toronto Zoology - Kipling | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Wed, 21 Apr 1993 14:51:00 GMT From: David Ward Subject: Keeping Spacecraft on after Funding Cuts. Newsgroups: alt.sci.planetary,sci.space,sci.astro In article <20APR199321040621@kelvin.jpl.nasa.gov>, baalke@kelvin.jpl.nasa.gov (Ron Baalke) writes... >In article <1993Apr20.204335.157595@zeus.calpoly.edu>, jgreen@trumpet.calpoly.edu (James Thomas Green) writes... >>Why do spacecraft have to be shut off after funding cuts. For >>example, Why couldn't Magellan just be told to go into a "safe" >>mode and stay bobbing about Venus in a low-power-use mode and if >>maybe in a few years if funding gets restored after the economy >>gets better (hopefully), it could be turned on again. > >It can be, but the problem is a political one, not a technical one. Also remember that every dollar spent keeping one spacecraft in safe mode (probably a spin-stabilized sun-pointing orientation) is a dollar not spent on mission analysis for a newer spacecraft. In order to turn the spacecraft back on, you either need to insure that the Ops guys will be available, or you need to retrain a new team. Having said that, there are some spacecraft that do what you have proposed. Many of the operational satellites Goddard flies (like the Tiros NOAA series) require more than one satellite in orbit for an operational set. Extras which get replaced on-orbit are powered into a "standby" mode for use in an emergency. In that case, however, the same ops team is still required to fly the operational birds; so the standby maintenance is relatively cheap. Finally, Pat's explanation (some spacecraft require continuous maintenance to stay under control) is also right on the mark. I suggested a spin- stabilized control mode because it would require little power or maintenance, but it still might require some momentum dumping from time to time. In the end, it *is* a political decision (since the difference is money), but there is some technical rationale behind the decision. David W. @ GSFC ------------------------------ Date: Wed, 21 Apr 1993 13:44:36 GMT From: fred j mccall 575-3539 Subject: Level 5? Newsgroups: sci.space In 18084TM@msu.edu (Tom) writes: >Nick Haines sez; >>(given that I've heard the Shuttle software rated as Level 5 in >>maturity, I strongly doubt that this [having lots of bugs] is the case). >Level 5? Out of how many? What are the different levels? I've never >heard of this rating system. Anyone care to clue me in? SEI Level 5 (the highest level -- the SEI stands for Software Engineering Institute). I'm not sure, but I believe that this rating only applies to the flight software. Also keep in mind that it was *not* achieved through the use of sophisticated tools, but rather through a 'brute force and ignorance' attack on the problem during the Challenger standdown - they simply threw hundreds of people at it and did the whole process by hand. I would not consider receiving a 'Warning' status on systems which are not yet in use would detract much (if anything) from such a rating -- I'll have to get the latest copy of the guidelines to make sure (they just issued new ones, I think). Also keep in mind that the SEI levels are concerned primarily with control of the software process; the assumption is that a well controlled process will produce good software. Also keep in mind that SEI Level 5 is DAMNED HARD. Most software in this country is produced by 'engineering practicies' that only rate an SEI Level 1 (if that). -- "Insisting on perfect safety is for people who don't have the balls to live in the real world." -- Mary Shafer, NASA Ames Dryden ------------------------------------------------------------------------------ Fred.McCall@dseg.ti.com - I don't speak for others and they don't speak for me. ------------------------------ Date: Wed, 21 Apr 1993 15:42:37 GMT From: Henry Spencer Subject: Level 5? Newsgroups: sci.space In article <1993Apr21.134436.26140@mksol.dseg.ti.com> mccall@mksol.dseg.ti.com (fred j mccall 575-3539) writes: >>>(given that I've heard the Shuttle software rated as Level 5 ... >>Level 5? Out of how many? ... > >... Also keep in mind that it was >*not* achieved through the use of sophisticated tools, but rather >through a 'brute force and ignorance' attack on the problem during the >Challenger standdown - they simply threw hundreds of people at it and >did the whole process by hand... I think this is a little inaccurate, based on Feynman's account of the software-development process *before* the standdown. Fred is basically correct: no sophisticated tools, just a lot of effort and painstaking care. But they got this one right *before* Challenger; Feynman cited the software people as exemplary compared to the engine people. (He also noted that the software people were starting to feel management pressure to cut corners, but hadn't had to give in to it much yet.) Among other things, the software people worked very hard to get things right for the major pre-flight simulations, and considered a failure during those simulations to be nearly as bad as an in-flight failure. As a result, the number of major-simulation failures could be counted on one hand, and the number of in-flight failures was zero. As Fred mentioned elsewhere, this applies only to the flight software. Software that runs experiments is typically mostly put together by the experimenters, and gets nowhere near the same level of Tender Loving Care. (None of the experimenters could afford it.) -- All work is one man's work. | Henry Spencer @ U of Toronto Zoology - Kipling | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Wed, 21 Apr 1993 15:02:33 GMT From: Andrew Rogers Subject: Life on Mars??? Newsgroups: sci.space In article <1993Apr20.120311.1@pa881a.inland.com> Don Schiewer, schiewer@pa881a.inland.com writes: >What is the deal with life on Mars? I save the "face" and heard >associated theories. (which sound thin to me) > >Are we going back to Mars to look at this face agian? >Does anyone buy all the life theories? try alt.alien.visitors ------------------------------ Date: Wed, 21 Apr 1993 15:30:26 GMT From: Henry Spencer Subject: Life on Mars??? Newsgroups: sci.space In article <1993Apr20.120311.1@pa881a.inland.com> schiewer@pa881a.inland.com (Don Schiewer) writes: >What is the deal with life on Mars? I save the "face" and heard >associated theories. (which sound thin to me) The "face" is an accident of light and shadow. There are many "faces" in landforms on Earth; none is artificial (well, excluding Mount Rushmore and the like...). There is also a smiley face on Mars, and a Kermit The Frog. The question of life in a more mundane sense -- bacteria or the like -- is not quite closed, although the odds are against it, and the most that the more orthodox exobiologists are hoping for now is fossils. There are currently no particular plans to do any further searches for life. >Are we going back to Mars to look at this face agian? Mars Observer, currently approaching Mars, will probably try to get a better image or two of the "face" at some point. It's not high priority; nobody takes it very seriously. The shadowed half of the face does not look very face-like, so all it will take is one shot at a different sun angle to ruin the illusion. -- All work is one man's work. | Henry Spencer @ U of Toronto Zoology - Kipling | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 21 Apr 1993 16:17 UT From: Ron Baalke Subject: Life on Mars??? Newsgroups: sci.space In article , henry@zoo.toronto.edu (Henry Spencer) writes... >In article <1993Apr20.120311.1@pa881a.inland.com> schiewer@pa881a.inland.com (Don Schiewer) writes: >There are currently no particular plans to do any further searches for life. Not quite true. One of the instruments on Mars Observer will be searching for potential fossil sites. >>Are we going back to Mars to look at this face agian? > >Mars Observer, currently approaching Mars, will probably try to get a better >image or two of the "face" at some point. It's not high priority; nobody >takes it very seriously. The shadowed half of the face does not look very >face-like, so all it will take is one shot at a different sun angle to ruin >the illusion. The face and the Viking landing sites will be targeted by the high-resolution camera on Mars Observer. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | The aweto from New Zealand /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | is part caterpillar and |_____|/ |_|/ |_____|/ | part vegetable. ------------------------------ Date: 21 Apr 1993 15:07:11 GMT From: Layne Cook Subject: Lindbergh and the moon (was:Why not give $1G) Newsgroups: sci.space All of this talk about a COMMERCIAL space race (i.e. $1G to the first 1-year moon base) is intriguing. Similar prizes have influenced aerospace development before. The $25k Orteig prize helped Lindbergh sell his Spirit of Saint Louis venture to his financial backers. If memory serves, the $25k prize would not have been enough to totally reimburse some of the more expensive transatlantic projects (such as Fokker's, Nungesser and other multi-engine projects). However Lindbergh ultimately kept his total costs below that amount. But I strongly suspect that his Saint Louis backers had the foresight to realize that much more was at stake than $25,000. Could it work with the moon? Who are the far-sighted financial backers of today? Layne Cook cook@apt.mdc.com McDonnell Douglas Space Systems Co. ------------------------------ Date: Wed, 21 Apr 1993 16:03:51 GMT From: Keith Mancus Subject: Lindbergh and the moon (was:Why not give $1G) Newsgroups: sci.space In article <1r3nuvINNjep@lynx.unm.edu>, cook@varmit.mdc.com (Layne Cook) writes: > All of this talk about a COMMERCIAL space race (i.e. $1G to the first 1-year > moon base) is intriguing. Similar prizes have influenced aerospace > development before. The $25k Orteig prize helped Lindbergh sell his Spirit of > Saint Louis venture to his financial backers. > But I strongly suspect that his Saint Louis backers had the foresight to > realize that much more was at stake than $25,000. > Could it work with the moon? Who are the far-sighted financial backers of > today? The commercial uses of a transportation system between already-settled- and-civilized areas are obvious. Spaceflight is NOT in this position. The correct analogy is not with aviation of the '30's, but the long transocean voyages of the Age of Discovery. It didn't require gov't to fund these as long as something was known about the potential for profit at the destination. In practice, some were gov't funded, some were private. But there was no way that any wise investor would spend a large amount of money on a very risky investment with no idea of the possible payoff. I am sure that a thriving spaceflight industry will eventually develop, and large numbers of people will live and work off-Earth. But if you ask me for specific justifications other than the increased resource base, I can't give them. We just don't know enough. The launch rate demanded by existing space industries is just too low to bring costs down much, and we are very much in the dark about what the revolutionary new space industries will be, when they will practical, how much will have to be invested to start them, etc. -- Keith Mancus | N5WVR | "Black powder and alcohol, when your states and cities fall, | when your back's against the wall...." -Leslie Fish | ------------------------------ Date: Wed, 21 Apr 1993 14:08:04 GMT From: "Matthew R. Feulner" Subject: Lunar Colony Race! By 2005 or 2010? Newsgroups: sci.space Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU In article <1993Apr20.234427.1@aurora.alaska.edu>, nsmca@aurora.alaska.edu writes: |> Okay here is what I have so far: |> |> Have a group (any size, preferibly small, but?) send a human being to the moon, |> set up a habitate and have the human(s) spend one earth year on the moon. Does |> that mean no resupply or ?? |> |> Need to find atleast $1billion for prize money. My first thought is Ross Perot. After further consideration, I think he'd be more likely to try to win it...but come in a disappointing third. Try Bill Gates. Try Sam Walton's kids. Matt matthew_feulner@qmlink.draper.com ------------------------------ Date: Wed, 21 Apr 1993 15:33:46 GMT From: Henry Spencer Subject: Lunar Colony Race! By 2005 or 2010? Newsgroups: sci.space In article <1993Apr21.140804.15028@draper.com> mrf4276@egbsun12.NoSubdomain.NoDomain (Matthew R. Feulner) writes: >|> Need to find atleast $1billion for prize money. > >My first thought is Ross Perot. After further consideration, I think he'd >be more likely to try to win it...but come in a disappointing third. >Try Bill Gates. Try Sam Walton's kids. When the Lunar Society's $500M estimate of the cost of a lunar colony was mentioned at Making Orbit, somebody asked Jerry Pournelle "have you talked to Bill Gates?". The answer: "Yes. He says that if he were going to sink that much money into it, he'd want to run it -- and he doesn't have the time." (Somebody then asked him about Perot. Answer: "Having Ross Perot on your board may be a bigger problem than not having the money.") -- All work is one man's work. | Henry Spencer @ U of Toronto Zoology - Kipling | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 21 Apr 93 13:32:33 From: Bob McGwier Subject: NAVSTAR positions Newsgroups: sci.space You have missed something. There is a big difference between being in the SAME PLANE and in exactly the same state (positions and velocities equal). IN addition to this, there has always been redundancies proposed. Bob -- ------------------------------------------------------------------------------ Robert W. McGwier | n4hy@ccr-p.ida.org Center for Communications Research | Interests: amateur radio, astronomy,golf Princeton, N.J. 08520 | Asst Scoutmaster Troop 5700, Hightstown ------------------------------ Date: 21 Apr 93 12:48:25 EDT From: Chris Jones Subject: Proton/Centaur? Newsgroups: sci.space In article <1r2aii$ivs@access.digex.net>, prb@access (Pat) writes: >In article <1993Apr20.211638.168730@zeus.calpoly.edu> jgreen@trumpet.calpoly.edu (James Thomas Green) writes: >>Has anyone looked into the possiblity of a Proton/Centaur combo? > >I don't know a whole lot on Proton, but given that it is a multi stage >rocket, up to 4 stages, it may not really need the Centaur, plus >it may end up seriously beating on said centaur. The Proton has been used in 2, 3, and 4 stage versions. The two stage version was used for the first 3 launches, while the 3 and 4 stage versions are used today. The four stage version is used mostly for escape (and geosynchronous?) orbits, while the 3 stage version is used for low earth orbits. Since this is the version that launched Mir and the Salyuts (and the add-on modules for Mir), as long as Centaur is smaller than Mir (which I believe it is), it should fit under the shroud. I vaguely recall that the Russians are developing a LH2/LOX upper stage for the Proton. -- Chris Jones clj@ksr.com ------------------------------ Date: 21 Apr 93 10:26:12 From: Al Globus Subject: Space Colony Size Preferences Summary Newsgroups: sci.space Some time ago I sent the following message: Every once in a while I design an orbital space colony. I'm gearing up to do another one. I'd some info from you. If you were to move onto a space colony to live permanently, how big would the colony have to be for you to view a permanent move as desirable? Specifically, How many people do you want to share the colony with? What physical dimensions does the living are need to have? Assume 1g living (the colony will rotate). Assume that you can leave from time to time for vacations and business trips. If you're young enough, assume that you'll raise your children there. I didn't get a lot of responses, and they were all over the block. Thanx muchly to all those who responded, it is good food for thought. Here's the (edited) responses I got: How many people do you want to share the colony with? 100 What physical dimensions does the living are need to have? Cylinder 200m diameter x 1 km long Rui Sousa ruca@saber-si.pt ============================================================================= > How many people do you want to share the colony with? 100,000 - 250,000 > What physical dimensions does the living are need to have? 100 square kms surface, divided into city, towns, villages and countryside. Must have lakes, rivers amd mountains. ============================================================================= > How many 1000. 1000 people really isn't that large a number; everyone will know everyone else within the space of a year, and will probably be sick of everyone else within another year. >What physical dimensions does the living are need to have? Hm. I am not all that great at figuring it out. But I would maximize the percentage of colony-space that is accessible to humans. Esecially if there were to be children, since they will figure out how to go everywhere anyways. And everyone, especially me, likes to "go exploring"...I would want to be able to go for a walk and see something different each time... ============================================================================= For population, I think I would want a substantial town -- big enough to have strangers in it. This helps get away from the small-town "everybody knows everything" syndrome, which some people like but I don't. Call it several thousand people. For physical dimensions, a somewhat similar criterion: big enough to contain surprises, at least until you spent considerable time getting to know it. As a more specific rule of thumb, big enough for there to be places at least an hour away on foot. Call that 5km, which means a 10km circumference if we're talking a sphere. Henry Spencer at U of Toronto Zoology henry@zoo.toronto.edu utzoo!henry ============================================================================= My desires, for permanent move to a space colony, assuming easy communication and travel: Size: About a small-town size, say 9 sq. km. 'Course, bigger is better :-) Population: about 100/sq km or less. So, ~1000 for 9sqkm. Less is better for elbow room, more for interest and sanity, so say max 3000, min 300. -Tommy Mac ------------------------------------------------------------------------- Tom McWilliams | 517-355-2178 (work) \\ Inhale to the Chief! 18084tm@ibm.cl.msu.edu | 336-9591 (hm)\\ Zonker Harris in 1996! ------------------------------------------------------------------------- ------------------------------ Date: Wed, 21 Apr 1993 15:05:45 GMT From: "Allen W. Sherzer" Subject: Why not give $1 billion to first year-long moon residents? Newsgroups: sci.space In article henry@zoo.toronto.edu (Henry Spencer) writes: >>This prize isn't big enough to warrent developing a SSTO, but it is >>enough to do it if the vehicle exists. >Actually, there are people who will tell you that it *would* be enough >to do SSTO development, if done privately as a cut-rate operation. Of >course, they may be over-optimistic. In spite of my great respect for the people you speak of, I think their cost estimates are a bit over-optimistic. If nothing else, a working SSTO is at least as complex as a large airliner and has a smaller experience base. It therefore seems that SSTO development should cost at least as much as a typical airliner development. That puts it in the $3G to $5G range. >You can also assume that a working SSTO would have other applications >that would help pay for its development costs. True it and the contest would result in a much larger market. But I don't think it would be enough to attract the investors given the risks involved. If you could gurantee the SSTO costs and gurantee that it captures 100% of the available launch market, then I think you could do it. Allen -- +---------------------------------------------------------------------------+ | Lady Astor: "Sir, if you were my husband I would poison your coffee!" | | W. Churchill: "Madam, if you were my wife, I would drink it." | +----------------------56 DAYS TO FIRST FLIGHT OF DCX-----------------------+ ------------------------------ End of Space Digest Volume 16 : Issue 476 ------------------------------