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 ; Sat, 17 Mar 90 01:31:16 -0500 (EST) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Sat, 17 Mar 90 01:30:41 -0500 (EST) Subject: SPACE Digest V11 #157 SPACE Digest Volume 11 : Issue 157 Today's Topics: Lunar Comm. Correction Re: What was Challenger really up to? Re: What was Challenger really up to? Re: Artificial Gravity rephrased Re: What was Challenger really up to? re:Ulysses at Jupiter Payload Status for 03/16/90 (Forwarded) RE: SPACE Digest V11 #145 Re: Sandia Railgun Re: SPACE Digest V11 #153 ---------------------------------------------------------------------- Date: Fri, 16 Mar 90 09:38 CST From: GOTT@wishep.physics.wisc.edu Subject: Lunar Comm. Correction Ooops. Paul Dickson points out that I didn't consider the fact that the tower can "see" twice the distance from the tower to the horizon, i.e. if X is 50km, the tower can "see" 50km in one direction AND 50 km 180 degrees away for a total of 100km. Please see revised figures below. The formula used to calculate the surface distance from an observer to the horizon is: X = R * ATAN [SQRT {h/R*((h/r)+2)}] where R is the objects radius h is the observers height X is the surface distance from the tower to the horizon (note: this equation was donated by yaron@astro.as.utexas.edu) According to the CRC 65th edition the radius of the moon is 1738.3 km plus or minus 1.1 km. For the purposes of the following calculations I chose R to be 1738.5km. h (in meters) X (km) 2*X (km) Number of towers needed to cover 1000km ------------- ------- -------- --------------------------------------- 100 18.6 37.2 27 200 26.4 52.8 19 400 37.3 64.6 16 500 41.7 74.6 14 1000 60.0 83.4 12 2000 83.4 120.0 9 I propose a total of 12 towers: Two 1000m tall ones, one at each base, and ten 500m tall relays between the two bases. Everything else still holds. George K. Ott University of WI - Madison High Energy Physics Department gott@wishep.physics.wisc.edu ------------------------------ Date: 16 Mar 90 22:31:51 GMT From: vsi1!v7fs1!mvp@apple.com (Mike Van Pelt) Subject: Re: What was Challenger really up to? In article <90075.021619GILLA@QUCDN.BITNET> GILLA@QUCDN.QueensU.CA (Arnold G. Gill) writes: > I heard the following story from a friend, and have absolutely no idea >about the truth/fantasy involved, since it is all completely new to me. It >goes like this. > > The real cause of the Challenger accident was not O-ring failure as we >are all meant to believe, but rather due to an accidental discharge of the >military laser being carried (illegally) up into orbit, which blasted through A laser wouldn't be illegal even if it were there. It would be unlikely in the extreme to be powered up and able to discharge during the ascent. (What would its power source be? Solar cells? Folded and stowed in the dark cargo bay. Nuclear reactor? Couldn't be running during the ascent, or it would irradiate the crew.) >the shuttle and exploded the fuel tanks. Proof of this is supposed to come >from the fact that there was a military laser expert on board the shuttle, who Who on the Challenger flight was supposed to be a military laser expert? I don't know of any of the crew who fits that description. >would have no purpose on the mission if no laser was included in the manifesto. Even if someone was on the flight who knew lasers, he wouldn't be so much of a specialist that he wouldn't be able to fill other roles in the mission. >Also, much of the cockpit recorder tape was never released and was actually >erased, as it contained comments pertaining to the military cargo that was >being launched. In addition, the fact that the cabin of the Challenger was >not located for a month, even though it was in the shallowest water around. >This was done to make sure that everybody on board was actually dead. The >O-rings were eventually blamed as part of the coverup. O-ring erosion was a known problem, and the parts of the SRB that were found had a large hole in it consistent with an O-ring failure. There's also the famous picture of the exhaust plume coming from the side of the SRB, and the puff of black smoke at launch. > If you ask me, this is a pretty wild story - something that the Christics >seem capable of. Nevertheless, I would be interested in all refutations of >the above line - but please, only serious refutations, nothing along the line >of "That is too idiotic/impossible to be true". I don't know enough to do it >myself. It sure does sound like the the kind of gonzo paranoia the Christics are justly infamous for. At the top of the list of refutations would be, why would a civilian teacher be on board if they were doing all this super-secret hush-hush stuff? Why not send it up on just another one of those secret DOD missions, and "leak" a story about a KH12 or Lacrosse satellite to AW&ST? -- Conspiracy theories: Bet you can't believe just one! -- "There is something about the underhanded use | Mike Van Pelt of power that makes it seem so shrewd, even | Headland Technology/Video 7 when it is abysmally stupid." -- Thomas Sowell | ...ames!vsi1!v7fs1!mvp ------------------------------ Date: 16 Mar 90 22:13:05 GMT From: zaphod.mps.ohio-state.edu!swrinde!cs.utexas.edu!news-server.csri.toronto.edu!helios.physics.utoronto.ca!ists!yunexus!utzoo!henry@think.com (Henry Spencer) Subject: Re: What was Challenger really up to? In article <90075.021619GILLA@QUCDN.BITNET> "Arnold G. Gill" writes: > I heard the following story from a friend, and have absolutely no idea >about the truth/fantasy involved... > The real cause of the Challenger accident was not O-ring failure as we >are all meant to believe, but rather due to an accidental discharge of the >military laser being carried (illegally) up into orbit... It is impossible to completely disprove this sort of paranoid fantasy, because the fantasizers can always claim that all the evidence you cite has been faked by the sinister conspiracy. That aside, it seems enormously unlikely. The biggest argument against it is, why bother disguising a military launch as a civilian one? It would have been much simpler to just make the thing a classified military launch with a plausible "leaked" cover story about it being a spy satellite. The US is nowhere near being able to put a laser of useful power output into orbit, and the one or two projects that are aiming at putting them up for military research are not particularly secret. >... there was a military laser expert on board the shuttle... I don't know who this would be, and it would prove nothing unless he also *wasn't* an expert on anything else. The Challenger crew all had good, solid, aboveboard reasons to be aboard. Then too, it seems very strange that they would pick a hush-hush disguised military launch for the Teacher In Space project. >Also, much of the cockpit recorder tape was never released and was actually >erased, as it contained comments pertaining to the military cargo that was >being launched... See above comments on impossibility of disproving paranoid fantasies. >In addition, the fact that the cabin of the Challenger was >not located for a month, even though it was in the shallowest water around. >This was done to make sure that everybody on board was actually dead... Thus making sure to give other members of the conspiracy maximum motive to spill the beans, before they were classified as expendable security risks too? Falling from 80,000 feet is normally considered 100% fatal without a one-month delay. Even if you were really paranoid about it, one or two days would have sufficed. >O-rings were eventually blamed as part of the coverup. Then it fooled Feynman, who was not easy to fool. By far the simplest explanation of the known facts about Challenger is that it happened pretty much as advertised. More complicated explanations are to be preferred only if they explain at least one fact that the simple one does not. "Never attribute to malice what can be adequately explained by stupidity." -- MSDOS, abbrev: Maybe SomeDay | Henry Spencer at U of Toronto Zoology an Operating System. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: 15 Mar 90 21:28:14 GMT From: amdahl!key!perry@csvax.caltech.edu (Perry The Cynic) Subject: Re: Artificial Gravity rephrased In article <86264@philabs.Philips.Com> rfc@briar.philips.com.UUCP (Robert Casey) writes: > If I was in that spaceship that was in _2001_, in the spinning section, seems > that I could throw a baseball in such a way as to cancel the spin speed. Then > the baseball would seem to take a circular path thru the spinning section at > the height from the floor where I threw it. Then I better duck at one > rotation! :-) Seen from outside the spinning section of the ship, the > baseball would be staying put in one spot. So, the artifical gravity wouldn't > grab the ball. Make sense? Sure. Let's look at the "natural gravity" counter-experiment: you stand on an idealized, spherical earth, and horizontally throw a baseball at circular orbit speed. Gee, the earth's gravity doesn't grab the ball! You even need to duck eventually. :-) What's really happening of course, in both experiments, is that you make use of the local geometry to impose pseudo-forces on your ball. And yes, atmospheric drag will get the ball, in either experiment. But that's just a minor detail :-) -- perry -- -------------------------------------------------------------------------- Perry The Cynic (Peter Kiehtreiber) perry@arkon.key.com ** What good signature isn't taken yet? ** {amdahl,sgi,pacbell}!key!perry ------------------------------ Date: 16 Mar 90 19:30:41 GMT From: zaphod.mps.ohio-state.edu!usc!elroy.jpl.nasa.gov!uniblab!stevo@think.com (Steve Groom) Subject: Re: What was Challenger really up to? In article <90075.021619GILLA@QUCDN.BITNET> GILLA@QUCDN.QueensU.CA (Arnold G. Gill) writes: >... but rather due to an accidental discharge of the >military laser being carried (illegally) up into orbit, which blasted through >the shuttle and exploded the fuel tanks. >...Nevertheless, I would be interested in all refutations of >the above line - but please, only serious refutations, nothing along the line >of "That is too idiotic/impossible to be true". I don't know enough to do it >myself. How about direct observation? The NASA gound cameras *saw* the flame coming from the leaking joint and burn through the booster support strut and into the external tank. If that was a laser, it didn't blast the tank, it blasted a hole in an O-ring in one of the right SRB's lower joints. (A fun theory though. Kinda like the wildly improbable yet still possible stuff they taught us to dream up in "Critical Thinking" in college. :-) ) -- Steve Groom, Jet Propulsion Laboratory, Pasadena, CA stevo@elroy.jpl.nasa.gov {ames,usc}!elroy!stevo ------------------------------ Date: Fri, 16 Mar 90 08:35:34 PST From: hairston%utdssa.dnet%utadnx@utspan.span.nasa.gov X-Vmsmail-To: UTADNX::UTSPAN::AMES::"space+@andrew.cmu.edu" Subject: re:Ulysses at Jupiter S Schaper writes: > I would like to add my vote for (since it has undoubtedly been already >proposed), that Ulysses would run its' instrumentation as it flys by Jupiter. ESA beat you to the punch. They've been planning to do that at least since 1986. Back then I was finishing my thesis on Jupiter's magnetosphere and asked the same question. My contact in the ESA (one of the research scientists on the Ulysses project) said yes, they would have all the instruments running during the Jupiter encounter. The reason this is interesting to those of us studying magnetospheres is because Ulysses will be the only probe that gets to the high latitudes in the Jovian magnetosphere. The Pioneers, Voyagers, and Galileo did (will) not get too far from the equatorial plane of Jupiter so we don't know first hand what the field is like outside of the +/- 15 degrees latitude range. In order to fly the solar polar mission, Ulysses will approach Jupiter from slightly above the ecliptic plane and then make a loop around the backside of Jupiter that will fling it southward below the ecliptic plane. So it will be able to sample the magnetosphere at latitudes of up to 70-80 degrees, and as any space physicist can tell you, most of the fun stuff goes on up near the poles. Now the bad news: >This would give us some intermediate data on changes there, such as the >missing cloud belt, the changes in the Red Spot, and vulcanism on Io, if it >has a camera, that is, to compare with Gallileo when it gets there. Sorry, this is strictly a particle and fields mission and according to the documents I have, there are no imaging experiments on board. Actually, there are some x-ray and gamma ray experiments, but those probably won't be very useful at Jupiter. Marc Hairston--Center for Space Science--University of Texas at Dallas SPAN address UTSPAN::UTADNX::UTD750::HAIRSTON It is against the regulations of the University of Texas System to hold opinions, so these must be facts. ------------------------------ Date: 16 Mar 90 19:45:42 GMT From: trident.arc.nasa.gov!yee@ames.arc.nasa.gov (Peter E. Yee) Subject: Payload Status for 03/16/90 (Forwarded) Daily Status/KSC Payload Management and Operations 03-16-90 -STS-31R HST (at VPF) - HST final closeouts ops and PDT testing along with west cell VPHD alignment were worked yesterday and will continue today. -STS-32R SYNCOM/LDEF (at SAEF-2) - LDEF deintegration continues. -STS-35 ASTRO-1/BBXRT (at O&C) - Yesterday preps for payload transfer to the canister were completed. The actual transfer will occur today. -STS-40 SLS-1 (at 0&C) - The systems test and ECS systems test were worked yesterday and will continue today. Also, experiment train disconnects from level IV and preps for transfer to level III/II will be active. -STS-42 IML (at O&C) - Staging activities on racks 3, 4, 7, 9, 10, and 12 were worked yesterday. Racks 3, 5, 7, and 12 staging activities are scheduled for today. -STS-45 Atlas-1 (at O&C) - Yesterday installation of the pallet joint kit on frame 4 was active. This work will continue today along with panel 15 CPSS installation. -HST M&R (at O&C) - Jiffy junction and ORUC cable system installations will be active today. ------------------------------ Date: Fri, 16 Mar 90 9:20 GMT From: "P D JONES, CRU" Subject: RE: SPACE Digest V11 #145 Could you please not send any more messages to this account. The previous holder, Mike Salmon, no longer works here. Thanks. ------------------------------ Date: 16 Mar 90 14:56:13 GMT From: wuarchive!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!watserv1!watdragon!watyew!jdnicoll@decwrl.dec.com (Brian or James) Subject: Re: Sandia Railgun Any idea what the desired tonnage to orbit per day is for the Hawaii coilgun? I don't think Hawaii is well tied into the US electric grid :) so the power source will be on Hawaii (Unless Hawaii refers to the entire chain in this context). Does the proposal mention where the power will be coming from? The US has some impressive mobile generators (The output of a nuclear powered aircraft carrier is comparable to some commercial generators, although probably harder to plug into), and I can't imagine the problem is a major one, but I have this mental image of the island browning out during launches (There was a very big lighting array for a rock show that browned out Paris the first [and only] time they turned all of its lights on at the same time. The local authorities were not amused). JDN ------------------------------ Date: Fri, 16 Mar 90 10:48:32 -0600 From: sedspace@walt.cc.utexas.edu (abrams) Subject: Re: SPACE Digest V11 #153 Francois, I, too, strongly support Strasbourg as a site for the permanent campus. I very strongly support a non-North American site and France is one of the few places that I know has the resources to support such a facility. I also heard that Todd was recently in Frnace visiting Marcel Pouliquen that might relate to this... Steve ------------------------------ End of SPACE Digest V11 #157 *******************