Date: Wed, 26 May 93 05:00:15 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #626 To: Space Digest Readers Precedence: bulk Space Digest Wed, 26 May 93 Volume 16 : Issue 626 Today's Topics: a question Detecting planets in other system Fred shoots from the hip Hey Sherz! (For real!) Cost of LEO (3 msgs) Hubble Servicing Mission Study Completed Moon Base Neil's words - an analysis (was Re: Neil's first words) One giant leap Question about B&W markings on US launchers Soyuz and Shuttle Comparisons (2 msgs) Stephen Hawking speaking in Seattle, WA Visible Astronomy (was Space Marketing) Why Government? Re: Shuttle, "Centoxin" 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: Tue, 25 May 93 14:42 GMT From: GRZEGORZ KRUK Subject: a question Does anybody know if Russian satelites emit EM waves in the range of frequency below 40kHz. What are their bands except radio and satTV ? Please reply to GKRUK@mee.tcd.ie Thanks in advance -Grzegorz ------------------------------ Date: 25 May 93 11:01:50 GMT From: clements@vax.ox.ac.uk Subject: Detecting planets in other system Newsgroups: sci.space In article <1993May25.025458.2349@cc.ic.ac.uk>, atae@spva.ph.ic.ac.uk (Ata Etemadi) writes: (Hi Ata!) > Anyone considered using Kilometric radiation ? I know we're being bathed in > it but it shouldn't be too difficult to filter out the near-Earth stuff using > two sensors (since its coming from close by). Planets with magnetic fields would > likely be emitting coherent radiation at these wavelengths making the job a > little easier. What you need is an underwater detector to filter out some of the > noise, since Kilometric radiation penetrates water a long way down. This would be > a darn good use for all those nuclear submarines out there. BTW I think the > military use this wavelength of radiation for communicating with their subs. > > best regards I can see a few problems with this suggestion... (1) Isn't there a plasma frequency effect in the interplanetary medium that blocks off kilometric radioation from outside the solar system? I remember A.C. Clarke talking all about this in Imperial Earth, but I don't remember any scientific analysis of this... (2) If planets with magnetic fields emit strong polarised radioation at theese wavelengths, won't magnetic stars do it even more? Since you'd have hardly any angular resolution at these wavelengths, how would you twell whether it was a planet or a star? > Ata <(|)>. -- ================================================================================ Dave Clements, Oxford University Astrophysics Department ================================================================================ clements @ uk.ac.ox.vax | Umberto Eco is the *real* Comte de dlc @ uk.ac.ox.astro | Saint Germain... ================================================================================ ------------------------------ Date: Tue, 25 May 93 12:26:23 EDT From: Tom <18084TM@msu.edu> Subject: Fred shoots from the hip Fred, paraprasing Tom's suggestion that He and Pat cool out a bit: >[much blithering deleted] T: >>You needn't reply. Unless you've changed you mind, any more on this won't >>mean much. F: >Quite true, Tommy, but then none of it has meant anything except for >your inane attempts to stroke your own ego, anyway. Is there an echo here? Wasn't this the reason I suggested you and Pat should take your flames to private mail? When did *your* flames turn into a vehicle for *my* ego? -Tommy Mac ------------------------------------------------------------------------- Tom McWilliams 517-355-2178 wk \ They communicated with the communists, 18084tm@ibm.cl.msu.edu 336-9591 hm \ and pacified the pacifists. -TimBuk3 ------------------------------------------------------------------------- ------------------------------ Date: Tue, 25 May 1993 10:05:43 GMT From: "Allen W. Sherzer" Subject: Hey Sherz! (For real!) Cost of LEO Newsgroups: sci.space In article <1ts2nl$910@hsc.usc.edu> khayash@hsc.usc.edu (Ken Hayashida) writes: >Pat, you and others convienently forget recovery of several multimillion >dollar satillites, I would think you wouldn't want to bring those up. >repair of solar max, don't remember what else went up on that flight so it may have been valid. >hubble space telescope ops, It would be cheaper to build and fly another. >Leasesat, This one never flew. Shuttle proved too unreliable to attract paying customers. >palapa, and westar, We spent about $400M to rescue $150M worth of hardware. Not what I would call successful. >most of all having intelsat snub shuttle for No, the Reagan Administration changed the policy to encourage commercial launchers. You got a problem with that? BTW, since it was us taxpayers who where picking up most of the tab, you should be glad. >deployment of their satillite and then coming back to the US gov't to >request a mission to rescue their spacecraft. (I'd say this is a pretty >stellar record of space operations.) Again, this was done at a huge loss which we taxpayers got to pick up the tab on. >Mass returned is important, You haven't shown a single instance of cost effective mass return. It therefore cannot be considered important. Will mass return someday be importatn? Sure; but not with Shuttle since it is too expensive. >while not all of these missions involved >mass returned from orbit, several did. Other missions included options >to return the vehicles to earth for later launch. At huge cost to the taxpayers. 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." | +----------------------22 DAYS TO FIRST FLIGHT OF DCX-----------------------+ ------------------------------ Date: 25 May 1993 10:30:28 -0400 From: Matthew DeLuca Subject: Hey Sherz! (For real!) Cost of LEO Newsgroups: sci.space In article henry@zoo.toronto.edu (Henry Spencer) writes: >Why do you assume these things require the shuttle? The most elaborate >in-space repair/salvage operations yet done -- Salyut 7 and Skylab -- >did not use the shuttle. For shame. Docking with a controlled space station with autonomous life support capabilities and tinkering with it is in no way comparable to working on a free-flying satellite that is in no way cooperating with you. 99.99% of the hardware up there that we could conceivably want to service can be done far more easily and effectively from the shuttle. (And before anyone points out that it is far cheaper in most cases to launch a replacement than to fund a shuttle flight to fix it: yes, but that's not the point here. We're talking about what can be done *assuming* you are going to fix the thing in the first place.) -- Matthew DeLuca Georgia Institute of Technology, Atlanta Georgia, 30332 uucp: ...!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!matthew Internet: matthew@phantom.gatech.edu ------------------------------ Date: Tue, 25 May 1993 15:24:33 GMT From: "Allen W. Sherzer" Subject: Hey Sherz! (For real!) Cost of LEO Newsgroups: sci.space In article <1ts3c5$93q@hsc.usc.edu> khayash@hsc.usc.edu (Ken Hayashida) writes: >>Why should he retract it if it is true? >Because I'm gonna show that when you look at the mass the Saturn V delivered >to orbit and the mass that the shuttle system has delivered to orbit, that >the shuttle will surpass the Saturn V's record. Even if true you won't find anybody but yourself who think it is the least bit relevant. Let's go back to the mover analogy: You want to move some stuff somewhere. Two movers submit bids which are identical except for cost. Mover A offers to do it for $3,000 and Mover B offers to do it for $9,000. When you ask about the huge cost difference, Mover B assures you he is actually giving the better deal since his truck weighs a lot more so your actually moving more mass per $$ than the cheaper mover. I, myself, would pick mover A and tell B that I don't care about his total mass but his payload. You, on the other hand, seem to be saying that you would pick B since he moves more mass. Is this in fact true? If so, why? >I am a doctor who is criticizing some of your *lack* of objectivity. Why is holding Shuttle to the same performance spect other launchers are held to a 'lack of objectivity'? >Hence your desire to delete the mass of the orbiter from the calculation >of the total mass delivered to orbit by the STS. Your insistance on including dead weight in your calculations makes you look like the person lacking objectivity. You want Shuttle to win and will work backwards to justify it. The rest of us took requirements and worked forward to conclude that Shuttle just wasn't cutting it. >I'm not aware that Pat is an engineer. I apparently am more realistic >than you are about spaceflight. Since you haven't posted a single fact or figure it is hard to see that as a valid statement. >I think some of you excessive shuttle >critics are overly enthusiastic about delta clipper. Why? >DC is not (to my knowledge) useful in the station program Using DC for station resuply will shave over $50 billion from Freedom's life cycle costs. Are you saying that isn't useful? >or in >medical applications. I think only shuttle can fulfill the requirements >for medical studies on orbit. Nonsense. What experiments couldn't be done with a suitable payload pallet? >It doesn't take a B.S. in engineering to do budgeting calculations Agreed. But we have seen NO budget calculations from you. I don't think you have posted a single number at all. >buddy. Perhaps, you should stop being critical of the orbiter and >prepare for your own cost-overruns in the DC-program. Well so far, there haven't been any. They seemed to have learned a lot on how to do procurement and are using these lessons to do the work on time and on budget. DC-X costs $70 million to build. It would have cost NASA four to ten times that much. Maybe it won't pan out. If so, you can be assured I will blow the whissle when it happens and drop it like a rock. My goal isn't DC, my goal is low cost access to orbit. Your goal seems to be Shuttle and nothing more. >I'm very skeptical of the projections made by the DC-program. Why? And don't say 'because Shuttle overran'. That is meaningless and proves that no project will ever work. What specific aspect of the DC effort do you think will fail and why? >They appear >overly simplistic and don't address several issues which have already >been raised by others on this net. Like what? >I seem to recall one post which went unanswered dealing with the >landing mode of the vehicle. I.E. how does a pilot or computer >land the thing? I would suggest you watch it next month. That should end that problem. If you want something sooner, look up a device called the "Lunar Module". You might also go to your airport and look at helicopters. 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." | +----------------------22 DAYS TO FIRST FLIGHT OF DCX-----------------------+ ------------------------------ Date: 25 May 1993 15:36 UT From: Ron Baalke Subject: Hubble Servicing Mission Study Completed Newsgroups: sci.space,sci.astro,sci.space.shuttle Mark Hess/Jim Cast Headquarters, Washington, D.C. May 25, 1993 (Phone: 202/358-1778) RELEASE: 93-96 HUBBLE SERVICING MISSION STUDY COMPLETED A task force established by NASA Administrator Daniel S. Goldin to review plans for the Hubble Space Telescope servicing mission concluded that, Rthe mission is achievable." This conclusion was driven by the fact that the spacecraft and most of its subsystems were designed for on-orbit maintenance. The Task Force on the Hubble Space Telescope Servicing Mission, chartered in late January, reviewed all aspects of the first servicing mission which is currently scheduled for December 1993. Dr. Joseph F. Shea was Chairman of the task force. RWe were asked to arrive at a judgement as to the likelihood of success of the repair and servicing mission,S said Shea. RIn our opinion, we think the mission is achievable." The task force pointed out, however, that the mission is complex and will require more EVA (spacewalk) time than any mission to date. Given this complexity, the task force recommended that a second HST servicing mission be planned 6 to 12 months after the STS-61 flight to handle tasks that might not be completed during the first mission or respond to failures that occur in the intervening months. Shea said planning and management changes, which have taken place over the past few months, will improve the likelihood of success. "We support the appointment of a Mission Director, and believe that such a position, with authority and resources, is necessary if the mission is to be carried out with confidence," Shea said. The task force report also concluded that a full end-to-end simulation of the EVA in the Neutral Buoyancy Simulator at the Marshall Space Flight Center, Huntsville, Ala., which is currently in the planning stage, is "essential to a successful mission." "There are some areas, like schedule, where we still have some concerns," Shea said. "We think the timelines for the EVAs are very tight and some of the hardware is not fully assembled. But we were very pleased to see that NASA extended the mission duration and the number of EVAs for the flight." -end- NOTE TO EDITORS: Copies of the report are available from the NASA Headquarters newsroom by calling 202/358-1600. ___ _____ ___ /_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov | | | | __ \ /| | | | Jet Propulsion Lab | ___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Never laugh at anyone's /___| | | | ___/ | |/__ /| Pasadena, CA 91109 | dreams. |_____|/ |_|/ |_____|/ | ------------------------------ Date: Tue, 25 May 1993 14:59:13 GMT From: "Allen W. Sherzer" Subject: Moon Base Newsgroups: sci.space In article <1993May24.182004.25681@ucsu.Colorado.EDU> fcrary@ucsu.Colorado.EDU (Frank Crary) writes: >>>Ah, but they are. The first mining facilities MUST be on the moon >>>because that's the only place where they will get a realistic test >>>where it doesn't take years to fix bugs. >True, if mining is the only goal of deep space missions. But if the >purpose of a Mars mission isn't mining, they the debuging a mining >operation isn't too usefull. Agreed. If all you want is a few flag and footprint Mars flights there is no reason to go to the moon. If you want to see longer term or permanent efforts on Mars, Lunar mining facilities will be a necessay step or it will simply cost too much. >Also, you are assuming the problems >encountered on the Moon would be similar to those encountered >elsewhere. I don't se why that would be the case. Not 100% but the closest we will come without going to Mars. I think a 'test flight' to the moon would be a good idea to flight qualify the Mars hardware. 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." | +----------------------22 DAYS TO FIRST FLIGHT OF DCX-----------------------+ ------------------------------ Date: Tue, 25 May 1993 16:07:29 GMT From: Roger Noe Subject: Neil's words - an analysis (was Re: Neil's first words) Newsgroups: sci.space In article DOCOTTLE@ukcc.uky.edu ("Darryl O. Cottle") writes: >One poster stated that the "a" WAS said but too softly for the radio >equipment to pick it up. It was spoken, although hurriedly, and is easy to miss because of radio interference. I can hear it. >If my memory serves Neil himself was the FIRST one to say that he had >not said what he had intended to say. You have a reference for that? I've heard Armstrong speak on this subject (albeit many years ago) and what I recall him saying is that he did say "for a man", as intended. >Now to the question of whether or not Neil said "for a man." I'm >not a speech pathologist To my midwestern ear, Neil's "for a man" is clear as day. Perhaps to others, it's more like "fera man". I can understand why those not accustomed to the many varieties of midwestern speech patterns continue to mishear these words. >To say the word "a" >in the middle, however, requires a shift of the jaw, tongue, and >lips all three. Not true, not at all. Keep in mind this is a schwa, an unstressed vowel with a sound like "uh". Also, the o vowel in "for" is schwa'd (phoneticists have a real term for this, I don't recall what it is) so that it's almost the very same vowel as the "a". If you want to speak like Neil, you run these two together with a little r in between. >reproduce my interpretation of what I heard. > >"That's one small step" "for man" "a giant leap for >mankind." This doesn't help your argument to get another word wrong in the "quote". That's "ONE giant leap" and there's a smaller pause between "one" and "giant". -- Roger Noe noe@cs.uiuc.edu Department of Computer Science 40:06:39 N. 88:13:41 W. University of Illinois (217) 244-6173 Urbana, IL 61801 USA ------------------------------ Date: Tue, 25 May 93 09:24:45 EDT From: "Darryl O. Cottle" Subject: One giant leap Yeah yeah I know. One giant leap. | | "Hey diddle didle "Anyone who says that they've never | The cat and the fiddle made a mistake has probably never | The cow jumped over the moon" done anything." | . . . Hey! That might work! Me | Far side here I come. (If its plagiarized its unconscious.) | The lurker +- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- -+ | (snail mail) |"I don't know what I'm doin'!| (voice) | |*Darryl O. (Doc) Cottle | If I ever DO figure it out,| 606-257-7577 | | Agricultural Economics | I'll prob'ly go HIDE!!" | or | |*431 Ag Engineering Bldg 2| "Brother" Dave Gardner | 606-231-6675 | | University of Kentucky |-----------------------------|--------------| |*Lexington, KY 40546-0276 | "Where were you born?" | | - - - - - <> - - - - - - | "Oh, are you one of them astrology dudes? | |* = short form of address | I'm a Cancer with a bad moon risin'!" | |--------------------------| Cheech Marin (Born in East L.A.) | | (electronic) +--------------------------------------------+ | docottle@ukcc.bitnet or else try docottle@ukcc.uky.edu | +- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- -+ ------------------------------ Date: Tue, 25 May 93 10:49:09 GMT From: Mike Parsons Subject: Question about B&W markings on US launchers Newsgroups: sci.space Forgive me if this is answered somewhere deep in the FAQ but: Why do several US launchers (especially early ones like Redstone, Titan and Saturn) have strong black and white stripe markings? Are they for recognition from a distance or something more involved like thermal control? As far as I'm aware, Russian and European launchers do not have, and have never had, such markings. Why not? --Mike. -- -- Mike Parsons, YCV, ESA ESTEC (European Space Research and Technology Centre) + Mail: P.O. Box 299, 2200 AG Noordwijk, The Netherlands \--[=]--/ Email: mike@yc.estec.esa.nl ------------------------------ Date: 25 May 93 07:22:27 EDT From: Chris Jones Subject: Soyuz and Shuttle Comparisons Newsgroups: sci.space In article , jbh55289@uxa (Josh Hopkins) writes: >clj@ksr.com (Chris Jones) writes: > >>In article <1993May24.024539.12481@ee.ubc.ca>, davem@ee (Dave Michelson) writes: >>>Note that the Soyuz-derived Zond *was* launched by a Proton (SL-12). This >>>may be the source of the confusion. > >>I thought it was the SL-13, but I don't have a reference here. Can anyone >>support or correct the following: > >>Proton 3 stage SL-12 D1 >>Proton 4 stage SL-13 D1e > >My data shows the Proton 4 stage version being launched first, in 1967, to earn >the SL-12 designation. The 3 stage D-1 was launched a year later and designated >the SL-13. Right, when I got home and looked it up, I saw Dave had it right and I had it backwards. Also, one source gave the "Sheffield designations" as D, D1, and D1e for the 2, 3, and 4 stage versions, while another used D1, D1h, and D1e. Sigh. (And the 3 stage version now flying is supposedly called the D1h' (that's a "prime") since the third stage was upgraded sometime in the '80s.) -- Chris Jones clj@ksr.com ------------------------------ Date: 25 May 93 07:50:48 EDT From: Chris Jones Subject: Soyuz and Shuttle Comparisons Newsgroups: sci.space In article <1993May24.174620.19060@ucsu.Colorado.EDU>, fcrary@ucsu (Frank Crary) writes: >In article <26956@ksr.com> clj@ksr.com (Chris Jones) writes: >>> The Soyuz is launched on the Soyuz (the >>>Soviet press named launch vehicles after the first spacecraft >>>they launched...) aka SL-4 aka "Type A-3" launch vehicle. > >>The Soyuz was not the first vehicle launched by this booster. The two Voskhod >>flights used this launcher, as did their (and Soyuuzes) unmanned precursors >>flown under the Kosmos banner. I don't know what was the first use. > >I think the Voskhods used the SL-2, but I suspect the Soviet press >criteria wasn't very exact: They probably used the first launch >they reported (Kosmos imssions usually aren't) not the real >first launch... As I pointed out in the part of my reply you omitted, the designations SL-4, A2 (NOT A3 -- no such beast as far as I can tell), and Soyuz refer to the same launcher. Yes, Voskhods were launched with this booster (I've seen a launch picture of Voskhod 1). I believe a skirt adapter had to be added to the upper stage since Voskhod, which essentially was a modified Vostok, had a conical aft section which had been designed to nestle inside the toroidal fuel tank on the Vostok (A1, SL-3) upper stage while the Soyuz upper stage was designed to interface with the Soyuz spacecraft, whose aft section is basically flat. The Voskhods were too heavy to use the Vostok launcher. They were also lighter than the yet-to-fly Soyuz spacecraft, so some trick with only partially fuelling the launcher was used, but they still ended up in higher orbits than had been used by Vostok. The low orbits of Vostok were a safety feature; they were designed to ensure orbital decay within 10 days in the event of a retrorocket failure, and all flights had 10 days of consumables aboard. In order to protect against retrorocket failure on Voskhod one of the changes made was to add a backup solid fuel retrorocket on the forward end of the craft. In fact, this system was used on Voskhod 2 when the primary liquid fuelled retrorocket failed. The first flight of the Soyuz launcher was almost certainly a Kosmos, and these satellites were typically announced, especially back in the early sixties, though not much real information was released. And to confuse things even more, the Molniya launcher (A2e, SL-6), which is essentially the Soyuz booster with an added 4th stage, is said to have first reached orbit in 1961 (though it must not have been realized at that time by whoever was in charge of handing out the SL designations, since 6 > 4). Lastly, the SL-2 is simply the the original Sputnik (A) launcher, consisting of the first two stages of the Vostok, Soyuz, and Molniya boosters. It's not clear what, if any, the differences are between the SL-1 and SL-2. I suspect that it was assumed at the time that a new launcher must have been used for Sputniks 2 and 3 since they were so much more massive than Sputnik 1. -- Chris Jones clj@ksr.com ------------------------------ Date: 25 May 93 15:46:43 GMT From: Lab Master Subject: Stephen Hawking speaking in Seattle, WA Newsgroups: sci.space Yesterday I bought two tickets to listen (?see?) Stephen Hawking speak in Seattle, WA on July 1. I was wondering if anyone has heard (seen) him speak recently (read: 1993), and hopefully you can tell me what I can (should) expect to hear. Let me see... it's at the Opera House, its co-sponsored by MicroSoft and Seattle University (a smallish (2500 students) private college), tickets started at US$22 and went to $50-something (I got two at $33--24 rows back, off to one side). Anything else? Email responses only, please. I will summarize if there is enough interest. Thanks. -Lab Master ------------------------------ Date: Tue, 25 May 1993 15:36:37 GMT From: Steve Willner Subject: Visible Astronomy (was Space Marketing) Newsgroups: sci.astro,sci.space Others have responded to most of the misconceptions, but I'll add a few comments. In article <1993May17.054859.21583@ucsu.Colorado.EDU>, fcrary@ucsu.Colorado.EDU (Frank Crary) writes: > Exactly what fraction of current research is done on the big, > visable light telescopes? From what I've seen, 10% or less > (down from amlost 100% 25 years ago.) That sounds like "dying" > to me... As others have pointed out, visible astronomy accounts for well over 50% of published papers. Moreover, every field of astronomy is growing rapidly. The 1967 Astrophysical Journal occupies 10 inches of shelf space and has 6.25 by 9.25 inch pages. The 1992 Journal, unbound and with a couple of issues missing, is 33 inches of 8.5 by 11 pages. That's an increase of over a factor of 5. My impression is that other journals have both grown faster and are more heavily weighted to visible observations. Both the fraction and the growth rate would go up if you include near infrared observations, which are usually made with the same telescopes. > That would be true, if adaptive optics worked well in the visable. Others more knowledgeable than I have addressed this topic, but it's my understanding that adaptive optics cannot give diffraction limited resolution over a wide field. Space observations will be a win for this kind of observation, once HST is repaired. > As for better locations, the Antarctic is one of the best and > I'd have trouble imagining an ad in a completely polar orbit... The Antarctic has some desirable properties, but calling it "one of the best" is premature, if not wrong. It is cloudy a lot, working conditions are severe, and travel is difficult. (Even if you observe remotely, getting spare parts is a problem.) Has the seeing ever been measured? > The next best I can think of is on the KAO (an airplane), > considering the scedueling they put into each flight, avoiding > an object in a known orbit should be travial. First of all, the airflow pattern limits the KAO seeing to roughly 5 arcsec, unless there has been a big improvement in the last couple of years. Second, it is only a 0.9-m telescope. (SOFIA will be around 3 m.) Third, it makes fewer than 80 flights per year with a maximum of 6.5 hours of observing time. (SOFIA might make 120 flights if fully funded.) Fourth, flight scheduling is already difficult. The aircraft heading is entirely determined by the object being observed, and the pilots get upset if you pick objects that don't get you back to the base before running out of fuel. Plus you have to avoid restricted areas, allow for winds, and keep the objects within the elevation limits of 35 to 75 degrees. Adding another constraint would not be trivial. Then in <1993May17.062435.24721@ucsu.Colorado.EDU>: > And also great limits: Adaptive optics don't work in the visable, and > don't work well in anything I'd call the near infrared. They are > very impressive below, say, 25 THz but that's hardly "visable" light. That's 12 microns, for those who prefer wavelengths. In fact, most of the work is devoted to visible wavelengths with some applications in the 1 to 3 micron range. Adaptive optics are unnecessary at longer wavelengths because 8 to 10 meter telescopes at good sites are diffraction-limited at 10 microns even without adaptive optics. It is true that adaptive optics systems are not widely available as facility instruments. Then in <1993May17.061128.23196@ucsu.Colorado.EDU>: > To be as bright as the full moon, in a 300-km orbit, it would > have to be about 1-km across. Roughly correct. > A balloon cuts down on launch weight immensely, but it > also gives you a very low-density object. Atmospheric > drag would pull it out of orbit in a matter of days. One would expect balloons to be in a higher orbit. There's enough slop in the "1 km" figure to allow that. (The effective albedo of the full Moon is 0.11. This is higher than the Bond albedo since the surface is highly backscattering.) -- Steve Willner Phone 617-495-7123 Bitnet: willner@cfa Cambridge, MA 02138 USA Internet: willner@cfa.harvard.edu member, League for Programming Freedom; contact lpf@uunet.uu.net ------------------------------ Date: 25 May 93 07:38:37 GMT From: Joseph Askew Subject: Why Government? Re: Shuttle, "Centoxin" Newsgroups: sci.space,talk.politics.space In article <1tqukk$dd9@access.digex.net> prb@access.digex.net (Pat) writes: >In article <1tovt2$bhl@st-james.comp.vuw.ac.nz> bankst@kauri.vuw.ac.nz (Timothy Banks) writes: >>In article <1tiqpo$o89@access.digex.net> prb@access.digex.net (Pat) writes: >Before my mailbox fully overflows with outraged aussies and kiwis, >I guess i should clarify my remarks. Lucky for you I read this first coz I was about to seriously flood your mailbox. The next time someone tries that I think I might post the name and address of every dead Australian soldier I can get my hands on. I think that would teach something close to manners perhaps :-) >I was referring to the >Post WW2 era. Specifically, the 50's - 90's. The Australians >regiments fought amazingly well in Both world wars, as did Indian >and African regiments. I notice you left the Kiwis out - too right too. O.K. I'm kidding. (BTW It is usually polite to Capitalise 'Aussie', which many people do not like foreigners using as they usually use inappropriately, as well as Kiwi.) Anyway just to put the record straight, 6.8% of the Australian population fought in WW2 with no conscription. All were volunteers. 64.8% of them became casualties. This is the highest number for any nation in the war and the percentage fighting is higher than the US or the Soviet Union or I believe the UK. In fact the only other country that is in the race is New Zealand who might tip us out marginally. >Australia and NZ both also contributed >during the Korean and Vietnam wars, but the fact is neither country >was supporting Serious deep water Navy capabilities, nor a >Nuclear weapons program, nor serious extra territorial military >programs. That is because we never had to. We paid for our own defense and them some. We sent soldiers to die in Vietnam and Korea and Malaya. None of these were our wars in the sense that they threatened us or that we took part for any other purpose but loyalty. The US has paid for all these things you mention but they have also reaped the benefits. They have nuclear power not us. They have a space program we don't. They can screw countries they don't like even if it is in defiance of international law we can't or at least don't. The US can and has defined other countries policies including ours much to the worlds benefit (at least usually.) The US has benefited most from this. At least until Japan came along they did. You get what you pay for. Who would say that the US has been cheated these last 50 years? Besides our spending would be much lower if it were not for our alliance with the US. >WW1 and 2 are over. My remarks are aimed at the current. Not in Luxemborg they are not. Joseph Askew -- Joseph Askew, Gauche and Proud In the autumn stillness, see the Pleiades, jaskew@spam.maths.adelaide.edu Remote in thorny deserts, fell the grief. Disclaimer? Sue, see if I care North of our tents, the sky must end somwhere, Actually, I rather like Brenda Beyond the pale, the River murmurs on. ------------------------------ End of Space Digest Volume 16 : Issue 626 ------------------------------