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/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID ; Fri, 9 Nov 1990 02:38:52 -0500 (EST) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Fri, 9 Nov 1990 02:38:21 -0500 (EST) Subject: SPACE Digest V12 #515 SPACE Digest Volume 12 : Issue 515 Today's Topics: Canals on Mars? Re: X-15 AP story on NASA's 1991 budget Re: Pioneer 11 Update - 10/30/90 Re: LLNL Proposal Mars Rover Update - 10/26/90 Re: You Can't Expect a Space Station to be Cheap Re: A great idea on how to fund NASA! Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription notices, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Date: 30 Oct 90 13:25:09 GMT From: ubc-cs!news-server.csri.toronto.edu!utgpu!watserv1!ria!uwovax!17001_1511@beaver.cs.washington.edu Subject: Canals on Mars? Regarding Martian Canals: The originator of the canal story was Giovanni Schiaparelli, an Italian astronomer, who in 1877 first mapped a complex web of narrow lines on Mars (others had seen a few in previous oppositions). He called them 'canali' meaning channels, and remained studiously vague about how they might be interpreted. In 1896 Percival Lowell began observations of Mars and developed his famous theory of an advanced civilization, a drying desert world and irrigation canals. Cerruli, Brenner and many others followed suit. Many 'saw' canals but there were always other explanations, so many believed in canals without believing in irrigation. For instance, Richard Proctor mapped them as rivers (See SCIENTIFIC AMERICAN SUPPLEMENT for 1888). Lowell's ideas became more famous because they were more extreme. The greek-french astronomer E.M. Antoniadi, one of the greatest visual observers of early this century, began by mapping canals but by the 1920s saw them for what they in fact are, essentially random blotches in a complex landscape (most of the blotches being dark boulder fields or sand dunes, the brighter areas being dustier). His great book 'La Planete Mars' in 1930 really killed the canals....for most. actually, the idea had such powerful public appeal that the first maps of Mars drawn for NASA in 1962-5, to help plan the Mariner 4 observations, still showed canals. These were by the U.S. Army Map Service and U.S. Air Force Aeronautical Chart and Information Center. Naturally, Mariner 4 wiped out the canals, but replaced it with another misconception which lasted for about 5 years - namely that Mars was moon-like. By the way, some might claim that the canal Agathodaemon (or Coprates) really did exist because it is the dark floor of the Valles Marineris. Not really - it is qualitatively different from all the rest of the canals, more akin to the regular dark areas and as such visible in telescopic drawings long befor the canals were discovered. Phil Stooke, Department of Geography, University of Western Ontario, London, Ontario, Canada N6A 5C2 ------------------------------ Date: 31 Oct 90 04:36:44 GMT From: uokmax!jabishop@apple.com (Jonathan A Bishop) Subject: Re: X-15 apengell@axion.bt.co.uk (alan pengelly) writes: > I've just read a very interesting book on the evolution >of the USA's winged spacecraft program (X-1 to Shuttle). >What strikes me most was the X-15 programme, which >was a fine piece of research, and which to me seemed to >be under exploited. In particular the decision not to >go for an uprated version (delta-winged + more power). >Given the X-20 cancellation as well, it seems to me that >the US was well ahead in this field quite early on, but >seemed to back-off. Was it money, was it apollo? Does >any one know what the capabilities of the uprated X-15 >were to be, ie speed and altitude? Also given what is >known now, would the X-20 have worked? Sounds like it's Melvyn Smith's book. Yes, it is very good. The uprated delta X-15 would have been launched from an XB-70 to give it a much greater initial velocity boost than the NB-52 could. The only real uprated X-15 was the X-15-A2 modification. The external fuel tanks it carried enabled the engine to burn longer, resulting in greater speeds; however, skin heating was much more severe than had been expected. To cope with this, the white ablative coating was added, but it was heavy. In the end, the A2 reached Mach 6.7. By this time, the limits of the XLR-99 were being pushed again. A planned modification would have added a ramjet. On the record setting flight, a mockup was carried, but a lambda shock caused by interference between the ramjet shock wave and the fuselage shock wave developed, burning the ramjet off and severely damaging the coating. The plane was never flown again. Without the extra fuel tanks, neither of the other X-15's could continue the high speed program, but they continued high altitude flights. I don't know exactly what the delta wing's performance would have been, but I can't see that it could have been more than about Mach 7 or 7.2 due to heating. It could have gone higher than the plain X-15. After reading the Smith's book, I too became interested in the X-20. I have written two short research papers on the subject. My main information source is an acquaintance who is doing his doctoral work in history on the X-20. The stated reason for cancellation of the X-20 was cost overruns and lack of results. Bob McNamara felt that the Manned Orbiting Laboratory, a Gemini variant, would be more cost effective (he later cancelled it, too). There are other reasons too, though. The X-20 was the first step in a three stage program to build an orbital or sub-orbital vehicle usable as a bomber, a troop transport, or other weapons platform. I believe (OPINION) that its development could have easily prompted a war with the Soviet Union. The technology, though, was not too sophisticated; we could have done it. If we had, I think that we would just now be going to the Moon for the first time, but we would be going to stay, and we would have built a permanent space station around 1975. -- jabishop@uokmax.ecn.uoknor.edu "Ground Control to Major Tom: Your circuit's dead; there's something wrong. Can you hear me, Major Tom?" -- David Bowie ------------------------------ Date: 31 Oct 90 01:32:40 GMT From: osu-20.ircc.ohio-state.edu!bunge@tut.cis.ohio-state.edu (Robert Bunge) Subject: AP story on NASA's 1991 budget 10/30/90 WASHINGTON (AP) _ President Bush's most ambitious space proposal _ colonizing the moon and sending a manned expedition to Mars _ are casualties to the deficit-cutting bill approved by Congress. The AP story reported the 1991 budget planners cut $37 million for early studies in Mars and Moon trips and trimmed at least $500,000 from the space station project. But, even with these cuts, NASA's budget was increased $1.6 million. The increase was a good bit smaller than what the administration had asked for. Bush had asked for a increase of $2.9 million. Buried at the bottom of the report is that Congress added $30 million to the $294 million Bush had requested for the operation and upgrade of HST. The report also said "Since (launch), the $1.5 billion instrument has malfunctioned." Apparently Bush's proposed HST budget was made before the launch and discovery of the spherical abberration. Budget trimmers also cut $210 million in research and technology, leaving it at the same level as 1990. $24 million was trimmed from the National Aerospace plane. $53.9 million was cut from the requested $4.4 billion shuttle operations budget and $30 million was trimmed from NASA's $53.9 million request for design of the next generation of (unmanned?) rocket. Finally, life sciences research was cut $25 million but, $12.1 million was reserved for SETI operations. Bob Bunge rbunge@magnus.ircc.ohio-state.edu ------------------------------ Date: 30 Oct 90 16:58:16 GMT From: lib!thesis1.hsch.utexas.edu@tmc.edu (Jay Maynard) Subject: Re: Pioneer 11 Update - 10/30/90 In article <1990Oct30.160542.20931@jato.jpl.nasa.gov> baalke@mars.jpl.nasa.gov (Ron Baalke) writes: > Pioneer 11 Update > October 30, 1990 > The Pioneer 11 spacecraft emergency was terminated at 3:29PM (PST) >yesterday. OK, I'll bite...how was it terminated? Did we get it back? Is it lost for good? Is some of it working, but not all? Inquiring minds want to know. -- Jay Maynard, EMT-P, K5ZC, PP-ASEL | Never ascribe to malice that which can jmaynard@thesis1.hsch.utexas.edu | adequately be explained by stupidity. "With design like this, who needs bugs?" - Boyd Roberts ------------------------------ Date: Tue, 30 Oct 90 19:37:20 EST From: John Roberts Disclaimer: Opinions expressed are those of the sender and do not reflect NIST policy or agreement. Subject: Re: LLNL Proposal >From: zaphod.mps.ohio-state.edu!wuarchive!rex!rouge!dlbres10@tut.cis.ohio-state.edu (Fraering Philip) >Subject: Re: LLNL Proposal >In article <9010262321.AA02614@cmr.ncsl.nist.gov> roberts@CMR.NCSL.NIST.GOV (John Roberts) writes: >>NASA has been trying for the last few years to convince people that a >>calculated probability that another Shuttle orbiter could eventually be >>lost should be regarded as a normal part of doing business, and the message >>never seems to sink in: >Well, the public in general realizes the risks. They realize there is a risk, but they have no way to quantify it or deal with it. The general view seems to be that there is no appreciable difference between a probability of one in ten and a probability of one in ten million. Countless examples come to mind, one of the better-known being the obsessive buying of large numbers of lottery tickets. A more immediate example for those living in the US (Canada too?) is "trick-or-treating" on Halloween (October 31), in which traditionally, costumed children visit neighborhood houses and ask for candy. This is done far less than in the past, because a very few kids get contaminated candy, and every parent is sure that his/her kid will get some too. Then some of these same parents go out and buy their children off-road vehicles, or passionately fight against bicycle helmet laws. In the same way that a cat may appear to be very clever in many ways, but will act stupidly in situations to which it is not well adapted, most people seem to walk through life in a sort of haze as far as effective risk assessment is concerned, and yet feel themselves fully qualified to call for stupid laws and stupid public policy decisions. The cat can't help it - for people it's through lack of proper education or through just not caring to think things through. I believe risk assessment for decision making would be a very good topic for greater emphasis in our educational system. >What upsets the >public in general, and those of us who track space in particular, is >that the shuttle, which is so expensive in the first place, is so >unsafe. Perhaps in relation to commercial airliners, for instance, but what about in relation to other launchers? I would welcome reliable statistics on Soviet launchers, but in the continuing absence of such, I can say I have seen no solid indication that the Shuttle is not the safest orbital launcher in existence. NASA considers it safer than any other US or European launchers. There are valid complaints that can be made about the Shuttle (notably cost and difficulty in meeting tight schedules), but given the current level of the art, I don't think safety is one of them. >It's not just the chance that another orbiter will be lost. It's the >chance that $ 3,000,000,000.00 (count those zeroes and imagine) worth >of sophisticated hardware will be broken up into bite-sized pieces, Every time a Titan IV is launched, ~$100 million of hardware ends up in the ocean. A year of launches in a worthy cause that wound up with $3 billion in the ocean would make everybody happy. For true cost of Shuttle accidents, one should consider the expected monetary losses from such in comparison to the total cost of maintenance, mission control, depreciation, and so on. I think most studies indicate that the expected cost from orbiter loss is only a small fraction of the total, which is another way of saying that perhaps too much emphasis is placed on safety. I agree with you that the public is likely not to perceive things this way, again due to lack of education in the matter. There is also no consistent viewpoint on what the valuation of a human life should be. >Phil Fraering >dlbres10@pc.usl.edu John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ Date: 31 Oct 90 00:27:18 GMT From: usc!zaphod.mps.ohio-state.edu!sdd.hp.com!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@ucsd.edu (Ron Baalke) Subject: Mars Rover Update - 10/26/90 From the "JPL Universe" October 26, 1990 "Robby Roves Arroyo as Prelude to Mars" JPL scientists and engineers have for the first time programmed a computer-driven planetary vehicle to traverse 100 meters of rugged natural terrain without human guidance. The test in September was considered a significent milestone in development of a semi-autonomous navigation system for a planet-roving vehicle. A mission using a computerized rover is expected to precede any manned mission to another planet. The rover, called "Robby" by the Section 347 experimenters, covered the 100 meters in about 4 hours and 20 minutes, moving cautiously about two meters at a time, then stopping to survey ahead another two meters. The test was in the rugged Arroyo Seco between the east lot and Oak Grove Park. The course was not preprogrammed in that the end of the course was not in the vehicle's stereo vision. It was obscured by foliage and rocks and no information about the specific terrain was provided in the testbed computer. By using the stereo television cameras, Robby surveyed the area and made its own map, two meters at a time. When it encountered a flat plane, it proceeded directly toward the goal, when it encountered an obstacle, it made a new map and modified its path to go around it, rather than over it. The unprecedented accomplishment was that the vehicle's stereo ranging perceived the terrain in three dimensions, and it artificial intelligence planned, without human help, a safe path to its goal. It was all done within a power and volume compatible with the onboard resources of a Mars surface vehicle. To complete the 100-meter semi-autonomous navigation milestone, the engineers had to integrate sensing, perception, planning and control into the self-contained vehicle. The long-range technology development goal is to go 20 kilometers, about 13 miles, in one day. The overall program goals are to develop the technology to enable planetary surface transportation with unmanned science and exploration rovers, along with mining and construction vehicles. Vehicles such as Robby, but space-qualified and even smarter, would cross the red, rocky wastes of Mars to find safe paths for future visits by space-traveling men and women. JPL's work is performed in cooperation with NASA's Office of Aeronautics, Exploration and Technology. ___ _____ ___ /_ /| /____/ \ /_ /| | | | | __ \ /| | | | Ron Baalke | baalke@mars.jpl.nasa.gov ___| | | | |__) |/ | | |___ Jet Propulsion Lab | baalke@jems.jpl.nasa.gov /___| | | | ___/ | |/__ /| M/S 301-355 | |_____|/ |_|/ |_____|/ Pasadena, CA 91109 | ------------------------------ Date: 30 Oct 90 04:25:30 GMT From: ubc-cs!news-server.csri.toronto.edu!utgpu!utzoo!henry@beaver.cs.washington.edu (Henry Spencer) Subject: Re: You Can't Expect a Space Station to be Cheap In article <6861@hub.ucsb.edu> 3001crad@ucsbuxa.ucsb.edu (Charles Frank Radley) writes: >Does SSX require RL-10 engines ? I thought it was aerospike. Aerospike is a nozzle concept, not a combustion chamber. The SSX proposal specified use of RL-10 chambers, and in fact as I recall it did not place much reliance on the aerospike nozzle. Hunter seemed to consider it both unproven (which it is) and relatively unnecessary (maybe). -- "I don't *want* to be normal!" | Henry Spencer at U of Toronto Zoology "Not to worry." | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 30 Oct 90 14:24:53 GMT From: thorin!grover!beckerd@mcnc.org (David Becker) Subject: Re: A great idea on how to fund NASA! dwex@cbnewsj.att.com (david.e.wexelblat) writes: >I didn't see a smiley on that followup, so: Hey -- have you ever heard >of a light-bulb? Your average incandescent bulb holds slighlty pressurized inert gas. Glass that thin could never keep O2 out of vacuum. The pressure is to keep the O2 out and the filament burning. -- David Becker I Dweam of Dweanie beckerd@cs.unc.edu ------------------------------ End of SPACE Digest V12 #515 *******************