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, 21 Apr 90 02:24:40 -0400 (EDT) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Sat, 21 Apr 90 02:24:01 -0400 (EDT) Subject: SPACE Digest V11 #297 SPACE Digest Volume 11 : Issue 297 Today's Topics: Re: Quick launches ( was: Intelsat Re: Drake Equation (was Re: Interstellar travel) PegBlimp (was Re: Pegasus launch from Valkyrie (or ...) Radar (was Re: Drake Equation Re: Drake Equation (was Re: Interstellar travel) Re: [HELP] Insult Re: Questions about the Voyagers Re: Pegasus launch techniques Re: SPACE Digest V11 #284 space digest Re: voyager images on cd ---------------------------------------------------------------------- Date: 20 Apr 90 17:00:27 GMT From: convex!ewright@uunet.uu.net (Edward V. Wright) Subject: Re: Quick launches ( was: Intelsat msjohnso@ensub.Wichita.NCR.COM (Mark Johnson) writes: >I have a vague recollection of reading an article on Minuteman I operational >tests in the 1960's. These were apparently conducted by drawing a missile >squadron out of a hat, and transporting the crewmen and one of their missiles >to Vandenburg for an operational test firing. Operational Readiness Test (ORT) firings of ballistic missiles are still conducted on a regular basis. That is one of the reasons the Titan II was retired -- because the Air Force had only about 50 of them, it couldn't afford to expend them in ORTs. By the time they were retired, no Titan II had been ORT fired in more than 20 years, leading to serious doubts about their operational readiness. Note that those Titans that are being converted into space boosters will undergo extensive refurbishment first. ------------------------------ Date: 20 Apr 90 06:22:14 GMT From: news-server.csri.toronto.edu!qucdn!gilla@rutgers.edu (Arnold G. Gill) Subject: Re: Drake Equation (was Re: Interstellar travel) In article <5209@cbnewsl.ATT.COM>, feg@moss.ATT.COM (Forrest Gehrke,2C-119,7239,ATTBL) says: > >Voyager level signals are what I would expect to be listening for >and those means required to make the search. I don't know of any >such search going on. There are dedicated SETI telescopes in the northern and southern hemispheres with million channel analyzers being operated by The Planetary Society. I can't remember what size dishes they use, but it is being done, and all by private funding. ------- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- | Arnold Gill | | | Queen's University at Kingston | If I hadn't wanted it heard, | | BITNET : gilla@qucdn | I wouldn't have said it. | | X-400 : Arnold.Gill@QueensU.CA | | | INTERNET : gilla@qucdn.queensu.ca | | -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- -=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=- ------------------------------ Date: 20 Apr 90 06:10:13 GMT From: bfmny0!tneff@uunet.uu.net (Tom Neff) Subject: PegBlimp (was Re: Pegasus launch from Valkyrie (or ...) I held off on this for a while because it sounded silly, but as I live with it it doesn't sound so silly anymore. What about launching Pegasus from a dirigible? OK, you don't get as many initial MPH as from a Buff, but the aircraft's speed is only a tiny fraction of what the rocket itself generates, so does it matter that much? (Specifically, could you make up for it in rocket performance given a dirigible launcher?) In exchange for slowing down, you get INFINITE time to hang around in the air and get ready for launch. And lots of space for a launch rack that's more freely optimized for its job, instead of fitting into a streamlined fuselage. There do exist big LTA designs considered buildable if you had a reason. The Soviets are supposedly going to start a big heavylifter for cargo work, according to a recent AvWeek. Just something to think about. -- "We must never forget that if the war in Vietnam \ $ Tom Neff is lost... the right of free speech will be X tneff@bfmny0.UU.NET extinguished throughout the world." -- RN 10/27/65 $ \ uunet!bfmny0!tneff ------------------------------ Date: 21 Apr 90 00:32:20 GMT From: zephyr.ens.tek.com!wrgate!mrloog!dant@uunet.uu.net (Dan Tilque) Subject: Radar (was Re: Drake Equation feg@moss.ATT.COM (Forrest Gehrke) writes: > >Hi Power pulsed microwave radars are the best source today for a >signal that might be detected at +LY distances. Unfortunately, >these do not operate continuously and when they are operating they >seldom stay on one path for very long. In any military >operation it's downright dangerous to do so for more than a few pulses. You're confusing wartime operation with peacetime operation. In peacetime, large military radars are fixed in location just like civilian radars and operate continuously. These are basically the ones that watch borders for violations as well as those used for routine training missions. However, since some of these are natural targets (NATO assumes that all it's radar sites in W. Germany will be lost in the first few minutes of war) there are backup systems which would operate like you say. Now the largest military radars (as I said in an earlier post) are large phased array systems which watch for ICBMs. The U.S. has five of them (or did that last I heard). Three of these, located in Alaska, Greenland and England, look for missiles launched from the Soviet Union. The other two are located on the U.S. east and west coasts and look for submarine launches missiles. These last two use over the horizon radar (using a troposcatter effect, I think) so much or most of their emissions probably do not escape to space. The Soviet Union has even more large phased array radars than the U.S. In order to detect ICBMs, these radars would have to have ranges of about 2 or 3 times that of regular radars. That means that (assuming similar receiver sensitivity) they would use 16 to 81 times the power of ordinary radar (which typically run about 2-5 MW). Source: U.S. Air Force training classes (unclassified) plus thinking about what they told us (not necessarily an encouraged activity). --- Dan Tilque -- dant@mrloog.WR.TEK.COM ------------------------------ Date: 20 Apr 90 20:09:17 GMT From: haven!aplcen!stda.jhuapl.edu!jwm@louie.udel.edu (Jim Meritt) Subject: Re: Drake Equation (was Re: Interstellar travel) In article <1990Apr19.092714.8548@metro.ucc.su.OZ.AU> bedding@extro.ucc.su.OZ.AU (Tim Bedding) writes: }From article <5209@cbnewsl.ATT.COM>, by feg@moss.ATT.COM (Forrest Gehrke,2C-119,7239,ATTBL): }> I don't expect any }> intelligence in this galaxy to initiate a supernova and then }> sentiently modulate it to get our radio astronomers' attention. }> }No, but if a supernova went off by chance, it would make sense to start }sending signals in the _opposite_ direction. Any ETs who studied the SN }closely might notice the signal (or may be smart enough to look for it). } }I vaguely remember someone suggesting this neat idea when SN1987a went }off. As far as I know, nobody has tried looking for radio signals in }the direction of it. Opposite direction relative to what? Why use radio waves? You have a very powerful emitter centrally located already. Why not just dump a mass into the central star of something that clearly does not belong there? A line for technium in the spectroscopic examination of a star should be a REAL indicator of a technological civilization nearby. Any ideas on how much of what could be used? "In these matters the only certainty is that nothing is certain" - Pliny the Elder These were the opinions of : jwm@aplcen.apl.jhu.edu - or - jwm@aplvax.uucp - or - meritt%aplvm.BITNET ------------------------------ Date: 20 Apr 90 06:18:56 GMT From: agate!shelby!helens!hanauma!joe@ucbvax.Berkeley.EDU (Joe Dellinger) Subject: Re: [HELP] Insult It's worse than you think. Texas passed all these "education reforms", that required that teachers and students be TESTED to see if they were learning the material. The tests were put together by committees "drawn from the finest teachers in Texas". Good idea, right? American education is in really bad shape, and these sorts of things will help, right? My sister was an Earth Science teacher in Texas. She obtained for me a copy of the Earth Science test that was given to HER students to see how well they knew Earth Science. Some of the questions: What planet has an atmosphere similar to Earth's? 1)Jupiter 2)Venus 3)Mercury 4)Mars correct answer: "Venus" The nearest galaxy to our own Milky Way Galaxy is located in Andromeda. What is it called? 1) Large Magellanic Cloud 2) Proxima Centauri 3) Andromeda Galaxy 4) Great Spiral correct answer: "Great Spiral" (The author of the question thought "Great Spiral" was the unique proper name, like "Milky Way". He also somehow got the idea that M31 was the closest galaxy, even though the LMC is a lot closer.) The nearest star to Earth besides our Sun is Proxima Centauri. How far away is it? 1) 8.978372 Parsecs 2) 4.333333 Light Years 3) 3782.483923 Billion Miles correct answer: 4.333333 Light Years (Wow, I didn't know they had measured the distance so accurately!) At what slope of the land can gullying not be contained? 1) 5 ft per 100 ft 2) 6 ft per 100 ft 3) 7 ft per 100 ft 4) 8 ft per 100 ft correct answer: 6 ft per 100 ft (Wow, I didn't realize it had nothing to do with soil type, climate, etc. I guess I'd better climb half dome again before its all covered with gullies.) Meteorologists model continents as what geometric shape? 1) Triangles 2) Squares 3) Trapezoids correct answer: triangles (I'm not kidding.) Etc. About 1/4 of the questions were OK. About 1/2 of them could be answered correctly if you had read ONLY the required textbooks. (Much of the information in those textbooks was years out of date, or "fuzzy" information was presented as being "hard". As a result, if you knew MORE than what was in the textbooks, the questions became impossible to answer "correctly"!) Stanford Earth Science professors I gave the test to _failed_! I sent back a critique of the test to the committee that made it; I went point by point and explained as politely as I was able WHY, for example, it was WRONG to list Proxima Centauri's distance as 4.333333 Light Years, just because the textbook they drew the question said it was "4 1/3 light years away". They wrote back, and said that they had a general policy of not accepting input from non high-school Earth Science teachers. Since I obviously spent so much time making my critique, they'd make a special exception for it, but really they thought the test must have been good since the FINEST high school Earth Science teachers in Texas had spent THOUSANDS of man hours writing it! So if a computer programmer can't even name the planets, it isn't necessarily his fault. And if he can't even name the planets, what's the big deal about some stupid robot having snapped a few pictures of Neptune? Without any background to appreciate Voyager with, how COULD he care? (Do you care about what values of C13 cause qSV waves in transversely isotropic media to triplicate?!) \ /\ /\ /\/\/\/\/\/\/\.-.-.-.-.......___________ \ / \ / \ /Dept of Geophysics, Stanford University \/\/\.-.-....___ \/ \/ \/Joe Dellinger joe@hanauma.stanford.edu apple!hanauma!joe\/\.-._ ************** Drive Friendly, Y'all! ****************************************** ------------------------------ Date: 18 Apr 90 22:34:20 GMT From: unmvax!nmtsun!nraoaoc@ucbvax.Berkeley.EDU (Daniel Briggs) Subject: Re: Questions about the Voyagers In article <1990Apr18.185031.25212@utzoo.uucp> henry@utzoo.uucp (Henry Spencer) writes: >Not a lot can be expected unless something unusual happens, notably having >one of the Voyagers pass out of the Sun's atmosphere and into the interstellar >wind. (There is some hope that this might happen before the Voyagers die, >but the location of the transition is very poorly known.) Even so, things >like plasma particle counts are exciting only to specialists. Oh come on Henry! This isn't some dry event to be measured only in particle counts. I'm not really a specialist in that field but I find the notion of the Voyagers reaching the heliopause to be TREMENDOUSLY EXCITING!! The heliopause is the transition between the solar wind and the interstellar medium (which is what I think you meant to say). We have some reason to expect that it may well be a fairly sharp transition. Put it into simple terms. This is THE EDGE OF THE SOLAR SYSTEM! How can you get any more fundamental than that? If the spacecraft lives that long we will be able to say (for instance) "On March 12, 1997 the Voyager II spacecraft passed the median point of the heliopause and became the first man made object to leave the solar system." I'd trade an asteroid encounter (but maybe not a Jovian one) for that anyday. This will be the first time we will have sent an object "OUT THERE". (To say nothing about the science data, which will be pretty interesting, too ;-) ----- This is a shared guest account, please send replies to dbriggs@nrao.edu (Internet) Dan Briggs / NRAO / P.O. Box O / Socorro, NM / 87801 (U.S. Snail) ------------------------------ Date: 20 Apr 90 16:25:36 GMT From: usc!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo!henry@ucsd.edu (Henry Spencer) Subject: Re: Pegasus launch techniques In article <9004182349.AA14764@aqua.whoi.edu> capnal@AQUA.WHOI.EDU (Alan Duester) writes: >However, those things carry a lot of typically overweight people, so it >might be able to move fast and high, 'specially if you're not worried >about fuel economies like the airlines supposedly are. Even figuring people at 200 lbs, a 40klb Pegasus is equivalent to 200+ people, the "+" being because Pegasus adds drag as well as mass. I don't think performance is going to be spectacularly better than normal airliner levels. -- With features like this, | Henry Spencer at U of Toronto Zoology who needs bugs? | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: Fri, 20 Apr 90 19:36:25 EDT From: ST701039@brownvm.brown.edu Subject: Re: SPACE Digest V11 #284 In response to the question whether or not there is a new orbiter in the Soviet space fleet, the answer is yes. I have actually seen pictures of the vehicles which showed it at that point to be almost completed. To the best of my know- ledge this shuttle will be manned (in contrast to Buran 1 which was unmanned). However, the article which I read also pointed out that this may be the last shuttle that the Soviets will build. The name of the new one was given as Bu- ran 2, even though that may just be lack of information. I'll look up more information. Uwe ------------------------------ Date: Fri, 20 Apr 90 14:23:00 +0300 From: Alexander Nezlin Subject: space digest X-Acknowledge-To: Hello, please remove me from the list of subscribers to the SPACE digest, or advise me how to do that. Thanks in advance, Alex Nezlin. e-mail : CONEZLIN @ WEIZMANN.BITNET ------------------------------ Date: 20 Apr 90 13:35:20 GMT From: usc!samsung!umich!terminator!UM.CC.UMich.EDU!Gavin_Eadie@ucsd.edu (Gavin Eadie) Subject: Re: voyager images on cd In article <1039@med.Stanford.EDU> rick@hanauma.stanford.edu (Richard Ottolini) writes: > >In fact the Neptune images are not yet released. Jupiter, Saturn and > >Uranus are available from NSSDC on CD-ROM. > > Miya from Ames said last summer that he thought JPL/policy was one year > delay from acquisition in order to give the principal investigators who > did the work first crack at the data. Correct! I'd expect to get the Neptune CD's toward the end of the calendar year by my guestimate. It is interesting that the CDs were released in the order Uranus, Saturn then Jupiter. I guess the technology became real after Uranus and then they worked back through the datasets. It is a lot of work to get this material together, properly cataloged and then set up for CD pressing and I'm impressed at the speed of the turnround. Gavin U of Michigan Information Services 535 West William Street, Ann Arbor, MI 48103 (313) 936-0816 ------------------------------ End of SPACE Digest V11 #297 *******************