Space Digest Tue, 20 Jul 93 Volume 16 : Issue 892 Today's Topics: 3-man Shuttle EVAs A new spin on Gravity -vs- space DC-X thermal protection European space For All Mankind: Will it be aired again?? GPS Altitudes (was: DC-1 & BDB) GPS in space (was Re: DC-1 & BDB) Head NASA Select Guy (was Re: NASA SELECT and scrambling.) Henry was right (as usual) (was Re: Space Movie/PR..) Info: Re STS-51 Launch Scrub Saturday MOON CABLE (4 msgs) Satellite viewing Space Movie/PR.. (2 msgs) Where is ESA's ERIN server? Why are meteor showers seasonal? 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: 19 Jul 93 13:48:32 GMT From: jeff findley Subject: 3-man Shuttle EVAs Newsgroups: sci.space,sci.space.shuttle > Provisions are > being made for 3-man EVAs, although there are no specific plans for any. What provisions are necessary for 3-man EVAs (besides carrying an extra suit)? How exactly do they get those three guys into and out of that small airlock? I know this has been done before, but I had problems getting the details of *how* this is done. Jeff -- __ __ __ __ /-------------------------------------------+-----------\ / \ | \ | \ / \ |"Have you noticed the way people's | The above | \__ | | |__/ | | intelligence capabilities decline sharply | opinions | \ | | | \ | | the minute they start waving guns around?"| are mine, | \__/ |__/ | \ \__/ |Dr. Who (Tom Baker in "The Horns of Nimon")| not SDRC. | jeff.findley@sdrc.com \-------------------------------------------+-----------/ ------------------------------ Date: Fri, 16 Jul 1993 15:18:31 GMT From: Bob Zwarick Subject: A new spin on Gravity -vs- space Newsgroups: sci.astro,sci.space In article <2218ab$qk5@lll-winken.llnl.gov> lawson@strat.llnl.gov (Bill Lawson) writes: >In article <1993Jul13.201454.2885@vss.fsi.com>, helenb@vss.fsi.com (Bruce Helenb) writes: >|> There is no such thing as centrifugal force, no matter how it's spelled. It's >|> mass accelerating inwardly while revolving >|> >|> Bruce Helenbart >|> Virtual Realist >|> >|> > >Help! I'm under attack -- by a virtual realist, no less! To arms: > >Centrifugal force is a fictitious or pseudo- force, as is the Coriolis force. >Yes, the only real force is the centripetal force due (in this case) to >gravity. But, doing your calculations in a rotating frame is often convenient, >especially if you happen to live in one, and so the concept is extremely >useful, and few, if any, physicists feel the need to add the extra syllables >to a name that is already too long. > > -- Bill Lawson But has it been 'proven' that gravity exists (as a real force)? -- =============================================================================== Bob Zwarick "Call me by name again, again forever, and never will it sound without response" =============================================================================== ------------------------------ Date: Mon, 19 Jul 1993 17:52:22 GMT From: "Richard A. Schumacher" Subject: DC-X thermal protection Newsgroups: sci.space In <1993Jul18.220843.13125@iti.org> aws@iti.org (Allen W. Sherzer) writes: >>Is this the remnant of the silly USAF requirement >>that the STS be able to fly 1,800 miles cross range. >It's not a silly requirement if you want to fly polar missions and can't >land just anywhere. Also, I don't know DC's crossrange but it is in the >same ballpark as Shuttle. Does this imply that DC has about the same lift as STS? ------------------------------ Date: Mon, 19 Jul 1993 13:24:23 GMT From: Dave Stephenson Subject: European space Newsgroups: sci.space charles.radley@pcohio.com (Charles Radley) writes: > -=> Quoting Dave Stephenson to All <=- > DS> drops of course. British Aerospace proposed a 4 man 'super > DS> command module' to fly on the Ariane 44 back in 1987. Could have > DS> taken 6 back to Earth as crew return vehicle. It got nowhere fast. > DS> a. It was British, B. it was like something the Americans had done! > DS> c. The french wanted Hermes! >David, >I think has more to do with the fact that the British government >wanted somebody else to pay for it. Britain spends remarkably >little on space. Sorry that was implied in a.. If it is British is usually is a good, even billiant idea, but no one wants to pay for it! -- Dave Stephenson Geological Survey of Canada Ottawa, Ontario, Canada *Om Mani Padme Hum 1-2-3* Internet: stephens@geod.emr.ca ------------------------------ Date: Mon, 19 Jul 1993 09:16:05 GMT From: Andy Clews Subject: For All Mankind: Will it be aired again?? Newsgroups: sci.space,sci.astro Richard E. Nickle (rick@trystero.com) wrote: : >Also, I would highly recommend reading the book. It is excellent - the : >first book I ever read that I didn't want to put down. : And the soundtrack to 'For All Mankind' is available. It's by Brian Eno : and called 'Music for Apollo'. Not quite correct - the soundtrack album is called "Apollo: Atmospheres and Soundtracks", but it is still by Brian Eno. Perhaps you were confused by titles of two of his other albums, "Music for Films" and "Music for Airports". Don't forget that For All Mankind was released on video last year (well, it was in the UK anyway). This was a godsend for me because my off-TV recording was munged by a spiteful VCR. I get the impression that the music soundtrack from the TV broadcast, whilst still by Eno, is different from that on the video - i.e. different tracks used in different places. Can anyone confirm this? -- Andy Clews, Computing Service, Univ. of Sussex, Brighton BN1 9QJ, England JANET: andy@uk.ac.sussex.syma OTHER NETWORKS: andy@syma.sussex.ac.uk ------------------------------ Date: Mon, 19 Jul 1993 21:18:40 +1200 (NZST) From: Bruce Hoult Subject: GPS Altitudes (was: DC-1 & BDB) Newsgroups: sci.space greg@defcen.GOV.AU (Greg Price) writes: > I bought a Magellan OEM board. Under "Operational Characteristics" it states > that max velocity is 950mph (1529 kph) and max accel is 2g. Under Evironmental > Characteristics, Altitiude, Operating it states -1000 to +58000 feet (-0.30km > to 17.68km). I'm thinking about the use of GPS units in gliders, and those limits are a bit of a worry. Most of you probably don't know that the 1995 World Champs, to be held at Omarama, New Zealand, intend to use GPS units as the official scoring mechanism for the first time in international competition. This will replace the ancient methods of a barograph trace (to prove you didn't land anywhere) and turn point photos (to prove where you went). The 950 mph limitation isn't a problem. The 50,000 ft limitation will be OK, but is uncomfortably close to the heights that may be achieved during competition flight in wave conditions -- glider flights between 30,000 and 40,000 ft are reasonably common in the area. 50,000 isn't in any real danger for the forseeable future, but the margin seems uncomfortably small. The max acceleration of 2g has me worried. Does this refer to stright-line acceleration only, or would a tight turn trigger the unit to stop working? It is *very* common to use 60 to 70 degrees of bank (2g-3g) on a continuous basis in strong thermals. -- Bruce ------------------------------ Date: Mon, 19 Jul 1993 14:56:39 GMT From: fred j mccall 575-3539 Subject: GPS in space (was Re: DC-1 & BDB) Newsgroups: sci.space In <229kmb$e5i@access.digex.net> prb@access.digex.net (Pat) writes: >In article <1993Jul17.182841.13504@mksol.dseg.ti.com> mccall@mksol.dseg.ti.com (fred j mccall 575-3539) writes: >>In <226do3$hcb@access.digex.net> prb@access.digex.net (Pat) writes: >> >>>Comments like "WATW" (We Are The World) Orbit does not sound like a >>>positive assessment. When there are numerous good reasons to push for >>>51 degree, 65 Degree, 73 Degree or even 90 or 97 degree orbits. >> >>Then people should be justifying those orbits based on their merits >>and talking about their drawbacks (like requiring some enhanced >>shielding, I gather) rather than trying to justify them as "the >>Soviets coulc play if we launch to high-inclination orbit". Having >Reasons for a High Inclination Orbit : >1) Cheap Soviet flights available. That's not a valid reason unless you've already decided to chuck the U.S. capability in this area in the interests of short-term monetary savings. >2) Improved Earth Observation Missions. This one actually makes sense, but the proponents of the high-inclination orbit seem to hardly ever mention it or the actual improvement that could reasonably be expected in return from it. >3) Improved Logistics Flow missions. Unless this is just another way of stating something like 1, it doesn't seem particularly obvious to me why this would be so. >4) Improved space science/engineering base. ( hihg inclination, >is a far more rigorous environment then low inclination. This sounds like saying "We should do it this way because it is *harder*." Somehow, that doesn't quite track for me. >5) Apparently ACRV return is simplified( This is what i was told, > I can't see an intuitive reason why this is). Only reason I can think of is that there would be more 'land' available to come down on with the high-inclination orbit. >> >>But Make vs Buy isn't a good paradigm if there is any sort of >>technology development involved in the alternatives. You have to >>count into the balance what sort of 'profit' we get from doing it >>ourselves and what kind of potential 'loss' there is if we don't do it >> >Make vs Buy is properly cognizant of the benefits of >Technology developement. Nevertheless, Every company does >Make this decision in it's business operations. Yes, and generally badly, since companies often fail to look at anything too far beyond the next balance sheet. >IBM Buys Micro-processors. DEC buys 4M DRAMS. Yes, and we can both see how healthy *those* two are, can't we? >Certainly there are intangible benefits from spooling up to >do things, but if that bleeds off developemnt money from >more vital activities, that is equally a problem. >Good Business people make these analyses. >>>COnsidering we put 1/3rd of our GNP into relying on certain very unstable >>>arab countries to sell us Oil, I don't see what the problem is. >> >>You have an alternative? >More energy Conservation, Higher energy taxes, developemnt of >low energy consumption Infra-structure. It's bizarre, that it >is cash wise cheaper for me to drive to Chicago then to >take the train ( The absolute lowest energy cost solution. It's actually not, if you properly amortize the vehicle the way the trains have to. This is one of the points of 'full costing' (in the economic sense). Lots of people make bad decisions because they figure that they already own the car so the cost of operating it (other than gasoline) doesn't count. >Why is it, cheaper for me to drive to work in DC (Home to the best >public transit system in AMerica) then to take metro. In part for the reasons I've already mentioned (perceptualy cheaper only, but not cheaper in actuality). In part because it's run by the same sort of mindset that runs institutions like Congress. -- "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: 19 Jul 93 14:01:18 GMT From: "Theodore F. Vaida ][" Subject: Head NASA Select Guy (was Re: NASA SELECT and scrambling.) Newsgroups: sci.space > >Theft of services? This seems rather extreme. > >It may interest you to know that there are people who receive NASA >press releases and press kits for various space missions, reprint >them, and sell them to subscribers. (Much of this stuff, in fact, you >and I read for "free" on sci.space.news.) I don't have names handy >but I belive you can find ads for them in *Final Frontier* or maybe >*Ad Astra*. Essentially they are doing on paper the same thing we're >talking about with cable. > >As far as I know, this is perfectly legal, and it's simple capitalism. >They're providing a service, and their customers are willing to pay >for it. (Since NASA does not copyright this material, it is in the >public domain and anybody can make copies.) Would you like to outlaw >this service too? > >(I also don't think we've established that there really IS a cable >company attempting to charge a premium for providing NASA Select >video. Mark Bixby merely reported on 9 July in sci.space that he'd >stumbled on a scrambled signal on a hidden channel of his cable >service.) > >It seems a good idea to crosspost this to rec.video.satellite to get >comments from knowledgeable people. Followups to sci.space. (?) > >-- > O~~* /_) ' / / /_/ ' , , ' ,_ _ \|/ > - ~ -~~~~~~~~~~~/_) / / / / / / (_) (_) / / / _\~~~~~~~~~~~zap! > / \ (_) (_) / | \ Hmm... you realize of course that we pay the press to carry our news to us, after all we cant go to every press conference ourselves. Ok, so its not illegal (as far as we know) but then think about the difference, NASA puts together press packs (which as I understand you can get if you are simply persistent, a friend of my has done it several times) for the press on the typical questions and some of the technical information. The press then turns sround and picks out the most sensation items (ones gaurantedd to bring in the revenues) and puts them on page B38 of the newspaper... those of us who have read the actual packets posted here know that mostly its not incredibly exciting and is actually just material collated from all the public documents that each part of the mission generates. NASA select is a direct linkup educational channel for anyone interested in space sciences, it is a supplementary educational tool for primary and secondary schools as wekk as some colleges when approriate material is available. It also has neato pictures of the suttle launching, doing interesting things and then landing. The cable company is different than the press in that it is using EDUCATIONAL material to make money. Consider that some teachiners in that area might like to have their kids watch the stuff to get them interested in science, and if Mom and Pop are forced to shell out 30$ a month, it aint happenin and johnny goes back to quietly knifing his neighbors.. ..sigh... -- ---------==============Sig file cover sheet=====================--------- ->POLAR CAPS<- or tfv0@lehigh.edu Student Konsultant Making the world safe for computing! Pages including this page: 1 ----- ------------------------------ Date: 19 Jul 93 10:03:21 -0600 From: Bill Higgins-- Beam Jockey Subject: Henry was right (as usual) (was Re: Space Movie/PR..) Newsgroups: sci.space In article <1993Jul19.022318.1771@ee.ubc.ca>, davem@ee.ubc.ca (Dave Michelson) writes: > In article <22cv4m$5di@agate.berkeley.edu> gwh@soda.berkeley.edu > (George William Herbert) writes: >> >>I've been working on a project to do a scale model Orion for special >>effects purposes with Footfall movie or miniseries in mind. It's >>really quite doable. A ten-meter diameter vehicle will easily work, >>and use up quite a bit of conventional explosives per "jolt". George, I would like to see more discussion of this idea. Could you post a bit more discussion of how to do it? (Possibly more appropriate to rec.pyrotechnics... do they ever discuss Orion models over there? I don't usually read it. To quote one Fermilab sage: "They must be typing with their noses, because they can't possibly have any fingers or toes left...") > Some time ago, Henry noted that he had seen a display relating to > a scale model demonstration of the Orion concept at NASM. Someone > (I forget who) posted back that Henry must be mistaken because those > items were not even in the NASM collection... More precisely, the dispute was about whether the NASM display included a film of the Orion model in operation. I think we decided that it did not, and that Henry must have seen it elsewhere. Lots of us have seen the model hanging in the museum. A good rule of thumb is: If Henry | Bill Higgins Spencer says something you | Fermi National Accelerator Laboratory disagree with, then you're wrong. | Internet: higgins@fnal.fnal.gov --Tom Fitzgerald, fitz@wang.com | Bitnet: higgins@fnal ------------------------------ Date: 19 Jul 1993 15:18:54 GMT From: "Michael C. Jensen" Subject: Info: Re STS-51 Launch Scrub Saturday Newsgroups: sci.space Here's the word I've heard re: "Why did STS-51 get scrubbed last Saturday?" Approximitly t-1:30 the launch control found a fail on the SRB holddown pyros, with these being set to "ARMED". This lead them to be concerned about a failure to "SAFE" prior to t-0, which would have caused a GLS engine shutdown. No other problems were reported through to the t-0:20 hold. Investigation of the systems is under work at this time. (Background info: The SRB pyros are a set of explosives which sever the bolts holding the SRB's to the launch pad. These are blown just prior to lift off to allow the shuttle to lift off from the pad cleanly. - note: this is my understanding of the system.. I may be slightly off.. if needed I can research out more presice info on this topic..) Mike -- Michael C. Jensen mjensen@gellersen.valpo.edu jensen@cisv.jsc.nasa.gov Valparaiso University - Electrical Engineering / NASA - Johnson Space Center "I bet the human brain is a kludge." -- Marvin Minsky *** Windows NT -- from the people who brought you edlin.. *** ---The opinions expressed are my own.. not NASA's or VU's..--- ------------------------------ Date: 19 Jul 1993 15:27:36 GMT From: Lab Master Subject: MOON CABLE Newsgroups: sci.space I've been following this "MOON CABLE/SKYHOOK" thread for a while, and I have a question (maybe a stupid question, but here goes). The main "expense" in putting something in orbit is energy, right? Wouldn't running something up a skyhook take just as much energy as launching it with a rocket? If so, what's the big advantage of a skyhook? -Lab Master ------------------------------ Date: 19 Jul 93 13:49:57 GMT From: "Theodore F. Vaida ][" Subject: MOON CABLE Newsgroups: sci.space For a real trat, check out this month's Analog magazine, the science fact article is a description (right down to the equations) of a new 'hook' called the supersonic skyhook... instead of anchoring it to the ground, it hangs above the atmosphere (within reach of a supersonic jet with attitude rockets) and provides the means of climbing to a higer energy position (for escape velocity). -- ---------==============Sig file cover sheet=====================--------- ->POLAR CAPS<- or tfv0@lehigh.edu Student Konsultant Making the world safe for computing! Pages including this page: 1 ----- ------------------------------ Date: Mon, 19 Jul 1993 16:16:24 GMT From: Herman Rubin Subject: MOON CABLE Newsgroups: sci.space In article <22eeh8$gmt@news.u.washington.edu> labmas2@hardy.u.washington.edu (Lab Master) writes: >I've been following this "MOON CABLE/SKYHOOK" thread for a while, and I >have a question (maybe a stupid question, but here goes). >The main "expense" in putting something in orbit is energy, right? >Wouldn't running something up a skyhook take just as much energy as >launching it with a rocket? If so, what's the big advantage of a skyhook? It is not merely energy, but the application of the energy. Also, it is not the case that energy can necessarily be minimized by shooting into orbit. Right now, to get something into orbit, there is the problem of using several accelerations to get it there. The biggest problem is overcoming gravity, so that an acceleration of more than 1 g is needed to even get anywhere. How much energy, and even more so, how much power, is needed to operate an elevator? We do not have to use high acceleration even to get up, and then high acceleration to adjust to the orbital height. Using a beanstalk would be like using an elevator, and not using a rocket with the need to accelerate quickly. -- Herman Rubin, Dept. of Statistics, Purdue Univ., West Lafayette IN47907-1399 Phone: (317)494-6054 hrubin@snap.stat.purdue.edu (Internet, bitnet) {purdue,pur-ee}!snap.stat!hrubin(UUCP) ------------------------------ Date: Mon, 19 Jul 1993 16:36:14 GMT From: Steve Linton Subject: MOON CABLE Newsgroups: sci.space In article <22eeh8$gmt@news.u.washington.edu>, labmas2@hardy.u.washington.edu (Lab Master) writes: |> I've been following this "MOON CABLE/SKYHOOK" thread for a while, and I |> have a question (maybe a stupid question, but here goes). |> |> The main "expense" in putting something in orbit is energy, right? Wrong. The main expense is the manpower required to design build, manage and test the hardware that does the launching. After that comes the energy to accelerate the engines and fuel tanks and the as-yet-unburnt fuel. Lifting a 1kg mass into GEO is roughly the equivalent of lifting it 6000km against Earth's surface gravity. This is easily seen to require 6 x 10^7 J or roughly 2 kWh. Say 10p (UK) at current prices, less in bulk. Doing the same with current rockets takes roughly L10000 (UK). Also with a skyhook you get (most of) the energy back when you bring things down. |> Wouldn't running something up a skyhook take just as much energy as |> launching it with a rocket? If so, what's the big advantage of a skyhook? ------------------------------ Date: Mon, 19 Jul 93 14:27:25 GMT From: Gary huntress Subject: Satellite viewing Newsgroups: sci.space We had an almost perfect stargazing weekend here in New England. My wife loves to sit outside when it isn't buggy and watch for shooting stars. She has very keen vision and also likes to pick out the satellites as they go by (my eyes aren't quite as good but I can sometimes follow them if she points them out to me). Anyway, she saw two things on saturday that we couldn't quite explain. One was a satellite that went bright-dim-bright-dim-bright-dim as it went across the sky. All that I could figure was that it may have been tumbling. The second event was three satellites traveling in formation! Going roughly north to south, they were in a skewed triangular formation and they had approximately equal brightness. I could think of no reason to have a number of satellites operate as a group, so the only explanatio I could come up with was chance. Given the 6K or so pieces of space junk, the odds are that a few should be moving together, right? Any thoughts? Gary Huntress ghuntres@nyx.cs.du.edu huntress@npt.nuwc.navy.mil ------------------------------ Date: Mon, 19 Jul 1993 12:42:43 GMT From: "Allen W. Sherzer" Subject: Space Movie/PR.. Newsgroups: sci.space In article <1993Jul16.020741.1@aurora.alaska.edu> nsmca@aurora.alaska.edu writes: >Is there any movies that take place in space? Other than the classic SF >(Sci-Fi) type movies and such.. Plymouth. Had it been a series it would have been a soap opera about the first Lunar colony. >Maybe do Arthur Clarke books (I think it was Clarke) about RAMA, or other liek >good books.... >It would be a grewat publicity plou to get people interested in space research. It's a good idea but I think your thinking along the wrong track. We need a show where people see THEMSELVES and not others in space. People currently don't see space as something for them but rather as something for a few scientists and astronauts. Plymouth would have been exactly what was needed. It was about ordinary people just like us living on the Moon. The show would have been about them and not their situation. This would be a way to generate a lot of interest if the show was properly done. Top Gun was great for Navy recruting and I understand that LA Law caused a swell in applications for law schools all over. 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." | +----------------------16 DAYS TO FIRST FLIGHT OF DCX-----------------------+ ------------------------------ Date: Mon, 19 Jul 1993 16:41:48 GMT From: Martin Brown Subject: Space Movie/PR.. Newsgroups: sci.space In article <1993Jul19.124243.12612@iti.org> aws@iti.org (Allen W. Sherzer) writes: >In article <1993Jul16.020741.1@aurora.alaska.edu> nsmca@aurora.alaska.edu writes: > [stuff deleted] > >>It would be a grewat publicity plou to get people interested in space research. > >It's a good idea but I think your thinking along the wrong track. We need >a show where people see THEMSELVES and not others in space. People currently >don't see space as something for them but rather as something for a >few scientists and astronauts. > Currently, people have very little opportunity to even see ANY space info, even when your very interested. Let's see, when the shuttle goes up CNN and other news organizations show the obligatory 20 second blurb on the blast-off, 1 minute segments during the evening news each day during the flight, followed by 10 second segments showing the landing. Not much opportunity there. My cable company doesn't show NASA Select, and isn't interested in doing so, saying there is no available capacity for new channels, while they waste one channel on _cable radio_! sheesh. I called JPL one day to see if they offered an auditorium for public viewing of NASA Select... nada. Maybe CSPN could show NASA Select instead of the British House of Commons when ever the shuttle is up. If you want greater public support for the space program, the public needs to be exposed much much more to it. Sci.space and sci.space.shuttle are as close as I can get. -- - mjb - mjb@netcom.com ------------------------------ Date: Mon, 19 Jul 1993 09:07:35 GMT From: Hartmut Wilhelms Subject: Where is ESA's ERIN server? Newsgroups: sci.space In article 229cdfINN9e@mephisto.gatech.edu, Troy Goodson () writes: >I was reading the latest Earth Observation Quarterly (published by ESA) and it >had a special section describing materials available from what I think was >called ERIN. They gave the user name and password for guests to log on but >did not give the address of the server. Does anyone know what that address >might be? I assume you are meaning the ESA ESRIN branch located at Frascati near Rome. Try: esrin.esa.it (192.106.252.1) via telnet --- Hartmut Wilhelms __/|__ Atmos Science Programme Office /_/_/_/ German Remote Sensing Data Center |/ DLR wilhelms@dlrtcs.da.op.dlr.de ------------------------------ Date: Mon, 19 Jul 1993 21:33:43 +1200 (NZST) From: Bruce Hoult Subject: Why are meteor showers seasonal? Newsgroups: sci.space henry@zoo.toronto.edu (Henry Spencer) writes: > Around 0100 GMT on Aug 12 -- evening of the 11th in North America -- > will be a good time to be in a dark area and watching the sky. Drat. That's the middle of the afternoon. What should it be like six hours later, or eight hours earlier? ------------------------------ End of Space Digest Volume 16 : Issue 892 ------------------------------