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, 19 Oct 1990 03:14:29 -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, 19 Oct 1990 03:13:31 -0400 (EDT) Subject: SPACE Digest V12 #468 SPACE Digest Volume 12 : Issue 468 Today's Topics: Re: Hubble Re: N-waste sea water dilution Re: Venus/Magellan, poles Re: Frame sequential TV in space Help needed in electric power for space applications Re: Launch cost per pound Re: Launch cost per pound Re: Man-rated SRBs (was Re: Junk the shuttle?) subscribe planetary north and names Re: Atmospheric nitrogen Re: Hubble 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: 18 Oct 90 22:11:00 GMT From: pyramid!lstowell@hplabs.hpl.hp.com (Lon Stowell) Subject: Re: Hubble It is unfortunate that NASA is totally unaware of the meaning of the words "Public Relations". I have seen prints of Hubble photos and am fairly impressed. If they ever fix the sucker will likely be overwhelmed. HOWEVER, I am extremely UNDERWHELMED that none of the photos have made it into mainstream media...specifically network TV. Is this because the networks refused to show the photo's or because no one thought to offer them? I still remember the NASA sponsored research back in the glory days of space...and the ABSOLUTELY TOTALLY INCOMPETENT p.r. types at NASA who refuse to make sure that the space race got full credit for the electronics revolution leading to modern reliable integrated circuits, medicine, etc. Who needed Proxmire with the NASA p.r. types on the job..... /| \'o.O' =(___)= U THPTH! ACKHH! ------------------------------ Date: 13 Oct 90 20:02:38 GMT From: sdd.hp.com!zaphod.mps.ohio-state.edu!caen!umich!sharkey!fmsrl7!teemc!fmeed1!cage@ucsd.edu (Russ Cage) Subject: Re: N-waste sea water dilution In article <1456@blenheim.nsc.com> alan@spitfire.nsc.com (Alan Hepburn) writes: >My point was that sufficient dilution would render the waste harmless. >The human race is not creating radioactivity; it is merely concentrating >that which is already here. By unconcentrating what we concentrate, we >are merely returning it to its natural form. Try again. You are correct that sufficient dilution would reduce the dose to harmlessness, but 1.) Such dilution is not possible. 2.) Our nuclear reactors produce waste which emits energy FASTER than the original ore. It is not creating energy, but it IS creating radioactivity in the short term. (In the long term, it depletes total radioactivity.) 3.) By trying to unconcentrate things in the manner you suggest, you make it a.) impossible to isolate any longer, and b.) susceptible to re-concentration through the food chain among other methods. -- Russ Cage Ford Powertrain Engineering Development Department Work: itivax.iti.org!cfctech!fmeed1!cage (Business only, NO CHATTY MAIL PLS) Home: russ@m-net.ann-arbor.mi.us (Everything else) I speak for the companies I own, not for the ones I don't. ------------------------------ Date: Thu, 18 Oct 90 14:09:00 PDT From: greer%utdssa.dnet%utadnx@utspan.span.nasa.gov X-Vmsmail-To: UTADNX::UTSPAN::AMES::"space+@andrew.cmu.edu" Subject: Re: Venus/Magellan, poles In SPACE Digest V12 #463, Jeffrey R Kell writes: >I read all the (various) definitions of "poles" and longitude direction, >spin, etc., but to ask a possibly silly question, HOW do you determine >where a longitude grid BEGINS? Find Greenwich, Venus? ( ;-) ) > >One of the (more) unbelievable parts of "Close Encounters" (and others) >was the use of our latitude/longitude co-ordinate system. While latitude >can be inferred (or at least argued over as of late) what basis (if any) >is there for longitude? Longitude and latitude are easy to define for a rotating sphere with at least one distinct and relatively permanent surface feature. However, in a brief foray to the library here, I was unable to find exact definitions of these for any body in the solar system except the Earth, of course, and the Moon. The prime meridian for the Moon is defined as the line on the Moon's surface that would always appear straight when viewed from the Earth if the Moon's libration were zero. In other words, it goes through the middle of the face pointing toward the Earth. For Mars, the the crater Airy is centered at exactly 0 degrees longitude, 0.5 degrees latitude, so I assume this is the definition of the prime meridian there. The prime meridian of Venus goes through Maxwell Montes, goes just east of a small but well defined mountain called Eisila near the equator, and also passes through Alpha Regio. Judging from the name, I would guess that some point in Alpha Regio defines zero degrees longitude for Venus. The prime meridian of Mercury doesn't seem to pass exactly through anything, so I couldn't even guess at its definition. I don't think it's possible to ascribe longitude to a gas giant. Even if you have something that lasts a long time like Jupiter's red spot, the cloud tops at different latitudes go around at different rates. All the mapped moons of the solar system have longitude defined, but just looking at the maps it usually isn't obvious why the prime meridian is where it is. Probably the U.S. Geological Survey has a pamphlet explaining this sort of thing. _____________ Dale M. Greer, whose opinions are not to be confused with those of the Center for Space Sciences, U.T. at Dallas, UTSPAN::UTADNX::UTDSSA::GREER "In no future war will the military be able to ignore poisonous gas. It is a higher form of killing." -- Fritz 'Father of Gas Warfare' Haber, 1919 ------------------------------ Date: 17 Oct 90 23:19:59 GMT From: Teknowledge.COM!unix!snmp.sri.com!larson@beaver.cs.washington.edu (Alan Larson) Subject: Re: Frame sequential TV in space In article <1398@ke4zv.UUCP> gary@ke4zv.UUCP (Gary Coffman) writes: -In article <1048@sun13.scri.fsu.edu> pepke@gw.scri.fsu.edu (Eric Pepke) writes: --I saw some TV pictures from the Shuttle on CNN last night, and when there --was much motion, the image left behind colored ghost images. This leads --me to believe that it is essentially a frame-sequential system. -- --If so, why is such a system used? I know that NTSC is notoriously phase --sensitive, but surely in this digital age we don't need to be limited by --that. Are the reasons historical? - -It's more likely that they are using old technology single tube cameras -that suffer from color lag under modest (ie: not full sun) lighting. -Newer cameras are not as bad about this, but NASA probably hasn't updated -the cameras due to the paperwork involved in rating anything for space -use on the shuttle. The newest cameras use chip pickups instead of tubes -and suffer practically no lag. Actually, it is frame (or field, I forget which) sequential color. It used to be that they would downlink the video and NASA select would precede it with warnings that the next transmission is "non-standard". Later, they would replay it in NTSC. About a year ago, they took a small (8mm, I think) camcorder up and used it for live and recorded NTSC. It apparently was quite successful. During STS-41, they used a second transponder on Satcom 2R, and often it had the sequential color images on it while the main NASA select channel had NTSC. The sequential color looks like a badly flickering monochrome image -- color bars on it really flicker! Alan ------------------------------ Date: 15 Oct 90 16:56:31 GMT From: eagle!news@ucbvax.Berkeley.EDU (David Liebal) Subject: Help needed in electric power for space applications I am about to start doctoral research in the above discipline area, and I am looking for sources for review purposes. I have heard that Rensellaer Polytechnic Institute is a leading academic center in this discipline, and most cited works I have been able to find to date are from RPI. Can anybody verify this, or point me in other directions? I will gladly summarize to the net if there is interest. Send e-mail. Dave ------------------------------ Date: 17 Oct 90 09:11:52 GMT From: ncrlnk!ncr-mpd!Mike.McManus@uunet.uu.net (Mike McManus) Subject: Re: Launch cost per pound In article <1117@helens.Stanford.EDU> joe@hanauma.stanford.edu (Joe Dellinger) writes: > I just thought I should point out that there's a major (and all too common) > economic misconception lurking below the surface here. A country can still > compete successfully in a service even if they are lousy at it! All that > matters is that they are less lousy at that than they are at other things, > and that they are willing to have a standard of living to match their overall > lousy productivity. I believe this is refered to as "The Law of Comparative Advantage". It's to your advantage to do what it is your least bad at, even if others are much better at it that you (summary of the idea, but not as nice as Joe's explanation and example!). -- Disclaimer: All spelling and/or grammar in this document are guaranteed to be correct; any exseptions is the is wurk uv intter-net deemuns,. Mike McManus Mike.McManus@FtCollins.NCR.COM, or NCR Microelectronics ncr-mpd!mikemc@ncr-sd.sandiego.ncr.com, or 2001 Danfield Ct. uunet!ncrlnk!ncr-mpd!garage!mikemc Ft. Collins, Colorado (303) 223-5100 Ext. 378 ------------------------------ Date: 18 Oct 90 15:43:06 GMT From: sdd.hp.com!samsung!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo!henry@ucsd.edu (Henry Spencer) Subject: Re: Launch cost per pound In article <1455.2719fd5e@iccgcc.decnet.ab.com> herrickd@iccgcc.decnet.ab.com writes: >I thought NASA was ordered by a president to leave those big shuttle >tanks in orbit for somebody to use. Did that disappear in the >Challenger problems ... No, actually I think it was post-Challenger. The order was to *make them available* for commercial use. Just leaving them in orbit is not a good idea; it costs payload (the old trajectory in which dropping the tank was actually more expensive is no longer used), the tanks are big enough and light enough to be brought down quickly by air drag, and they would be punctured quickly by debris. NASA is agreeable in principle to commercial use of the tanks, but details are still being negotiated. -- "...the i860 is a wonderful source | Henry Spencer at U of Toronto Zoology of thesis topics." --Preston Briggs | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 18 Oct 90 16:20:18 GMT From: sdd.hp.com!wuarchive!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo!henry@ucsd.edu (Henry Spencer) Subject: Re: Man-rated SRBs (was Re: Junk the shuttle?) In article <3338@orbit.cts.com> schaper@pnet51.orb.mn.org (S Schaper) writes: >How to the throttleable solids developed by a private US company using LOX for >the oxidizer measure up in this evaluation? These are not solids; they are hybrid rockets. (That is the correct term for rockets in which one component is liquid and the other is solid.) The Amroc hybrids are sort of halfway in between liquids and solids in a lot of ways, including the ones recently discussed. They still have the big combustion chamber and the inability to test the flight-ready engine. On the other hand, they can be throttled or shut down. And I don't think they have solids' sensitivity to things like cracks and bond failures, at least not to the same extent. -- "...the i860 is a wonderful source | Henry Spencer at U of Toronto Zoology of thesis topics." --Preston Briggs | henry@zoo.toronto.edu utzoo!henry ------------------------------ ReSent-Message-ID: Resent-Date: Thu, 18 Oct 90 13:09:30 EDT Resent-From: Harold Pritchett Resent-To: Space discussion group From: System Administrator Date: Thu, 18 Oct 90 12:35:26 GMT Subject: subscribe This message was originally submitted by root@CMS.SCP.AC.UK to the SPACE list at FINHUTC. If you simply forward it back to the list, it will be distributed with the paragraph you are now reading being automatically removed. If you edit the contributions you receive into a digest, you will need to remove this paragraph before mailing the result to the list. Finally, if you need more information from the author of this message, you should be able to do so by simply replying to this note. ------------------ Message requiring your approval (1 line) ------------------- please forward information on subscribing to this list. ------------------------------ Date: 17 Oct 90 14:26:22 GMT From: sdd.hp.com!wuarchive!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!watserv1!ria!uwovax!17001_1511@ucsd.edu Subject: planetary north and names Regarding two recent postings: The IAU north direction on planets and satellites is really only intended to be used for cartographic purposes, not to be imposed on geophysicists and the like. There is always going to be confusion with this whatever definition is adopted - planets on their sides like Uranus and Pluto, retrograde rotation, magnetic fields in opposite senses and so forth. Look at the Halley literature to see how confusing the situation is - if you use the counter- clockwise pole as north, it is (assuming we know how it rotates) the one which points south of the invariable plane.... so the big active region at the 'north' pole shoots a jet out in a southward direction on the sky. Clear? Of course not, but if you let the other pole be north and the rotation be retrograde you contradict most of the existing literature. I use carto- graphic coordinates with the IAU definition of north, but I would not try to impose it on anybody else. The only thing that really matters is that you let people know which north you are using so they can convert if necessary. Latin names on planets are useful when dealing with an international community of scientists. How can we use 'vernacular' names like 'Mariner valleys' in an international setting without being offensive? Look at medical terminology for all those squishy things inside us, or the latin names of genera and species of living things - latin is not really a dead language in science after all. Besides, it is just as easy to learn words like 'tessera' or 'tholus' as simple terms like 'graben' or 'caldera', without thinking of them as words in a foreign language. Incidentally, on a planetary subject, I have just received the new soviet atlas of Venus (ATLAS POVERKHNOSTY VENERY) from Sojuzkarta. It includes the entire set of Venera 15 and 16 radar images, contour and geological maps in a very attractive volume. The text portion is only in russian but a gazetteer at the end lives latin equivalents. A beautiful book and a valuable historical record of planetary exploration. Well worth having in any good library. Phil Stooke, Department of Geography, University of Western Ontario, London, Ontario, Canada N6A 5C2 ------------------------------ Date: 17 Oct 90 06:25:01 GMT From: crash!orbit!pnet51!schaper@nosc.mil (S Schaper) Subject: Re: Atmospheric nitrogen Chris Jones refers to studies showing increased judgement in an atmosphere with less nitrogen. so, how do we start piping the Argon into the White House and Congress? UUCP: {amdahl!bungia, uunet!rosevax, chinet, killer}!orbit!pnet51!schaper The necktie is a device of Mordor ARPA: crash!orbit!pnet51!schaper@nosc.mil INET: schaper@pnet51.cts.com ------------------------------ Date: 17 Oct 90 21:20:17 GMT From: haven!uvaarpa!murdoch!astsun7.astro.Virginia.EDU!gsh7w@louie.udel.edu (Greg Hennessy) Subject: Re: Hubble In article <4202@lib.tmc.edu> jmaynard@thesis1.hsch.utexas.edu (Jay Maynard) writes: #...or were led to think by biased, NASA-bashing news coverage. In fact, the #last word I heard was that the HST would meet - but not exceed - its design #specs with the existing optics. This is incorrect. HST will NOT meet its design specs, if for no other reason than the spherical abberation means basically a loss of about three magnitudes in brightness of the observable stars. While many neat and nifty things can be done with deconvolution and other image restoration techniques, you can never get back as what you would have had. The second generation instruments *MAY* be able to correct for the spherical abberation. That will depend on how well the wavefront is known at the time of the design of the instruments. Since some of the 2nd generation instruments are well along in the design phase, there is not much time to exactly characterise the wave front. #Of course, the media NASA-bashers didn't want _this_ to get out; it would #get in the way of their crusade. The fact that the HST's real capabilities #haven't gotten the coverage that the early troubles did is an eloquent #comment on just how the media manipulates the public. While NASA bashers certainly exist, part of the problem (in my opinion) is that the PI's of the instruments were not experts in the field of image reconstruction, and were unsure of its capabilities. When the first images were being shown, the optical astronomers were cursing the air blue, while the radio astronomers were saying, "Hey wait, that PSF doesn't look so bad....". Also it is human nature that bad news gets more headlines than good news. -- -Greg Hennessy, University of Virginia USPS Mail: Astronomy Department, Charlottesville, VA 22903-2475 USA Internet: gsh7w@virginia.edu UUCP: ...!uunet!virginia!gsh7w ------------------------------ End of SPACE Digest V12 #468 *******************