Return-path: X-Andrew-Authenticated-as: 0;andrew.cmu.edu;Network-Mail Received: from andrew.cmu.edu via trymail for ota+space.digests@andrew.cmu.edu ID ; Sat, 9 Jul 88 23:24:03 -0400 (EDT) Received: by andrew.cmu.edu (5.54/3.15) id for ota+space.digests; Sat, 9 Jul 88 23:22:42 EDT Received: by angband.s1.gov id AA07907; Sat, 9 Jul 88 20:23:11 PDT id AA07907; Sat, 9 Jul 88 20:23:11 PDT Date: Sat, 9 Jul 88 20:23:11 PDT From: Ted Anderson Message-Id: <8807100323.AA07907@angband.s1.gov> To: Space@angband.s1.gov Reply-To: Space@angband.s1.gov Subject: SPACE Digest V8 #265 SPACE Digest Volume 8 : Issue 265 Today's Topics: Re: Some more launch loop stuff... Re: Some more launch loop stuff... Re: Bureaucracy vs. space Mir elements, epoch 25 May Re: Mir elements, epoch 25 May Re: Space Station Names Re: Space Suits RE: SPACE Digest V8 #240 Re: Naming the space station. Re: Nuclear bombs Tours of NASA Ames during Usenix Space Digest skin tight space suits Re: Some more launch loop stuff... ---------------------------------------------------------------------- Date: 1 Jun 88 02:49:17 GMT From: mnetor!utzoo!utgpu!water!watmath!looking!brad@uunet.uu.net (Brad Templeton) Subject: Re: Some more launch loop stuff... What ever happened to the good old fashioned 500 mile linear acellerator? At 3.5g for 3 minutes 20 seconds you hit orbital velocity. You have to correct to circular with a reaction rocket later of course, and you have to also get back the velocity you lose to air. But the point is we could build such a thing. 500 miles isn't that long, with mass production techniques. If it costs $20 million per mile to build, that's only $10 billion -- lots less than the space scuttle program. Share it with the Russians, Japanese, Canadians and ESA even if it costs $100 million per mile. Float it at sea and have it shoot up the Rockies or the Andes. Stretch it over the desert. Use it as a supercollider when it isn't busy launching. The launch loop would fail in a bad way. Geostationary towers can't stand because they would be hit by satellites. I think it's this or super fast scramjets, folks. -- Brad Templeton, Looking Glass Software Ltd. - Waterloo, Ontario 519/884-7473 ------------------------------ Date: 1 Jun 88 16:13:05 GMT From: mnetor!utzoo!henry@uunet.uu.net (Henry Spencer) Subject: Re: Some more launch loop stuff... > ... Also, the segments wouldn't wind up in Earth orbit. > They would go into solar orbit. Nothing like having a few thousand > one kilo chunks of iron flying about in an earth intersecting solar > orbit. :-( Not to worry, there are millions of one-kilo-sized nickel-iron meteorites out there already. The only reason space junk is a concern in Earth orbit is that near-Earth space, especially the most interesting regions, isn't very big. We can't totally disregard the issue elsewhere, but given the natural background level already present, it will be a while before it's a real concern. -- "For perfect safety... sit on a fence| Henry Spencer @ U of Toronto Zoology and watch the birds." --Wilbur Wright| {ihnp4,decvax,uunet!mnetor}!utzoo!henry ------------------------------ Date: 1 Jun 88 16:31:04 GMT From: mnetor!utzoo!henry@uunet.uu.net (Henry Spencer) Subject: Re: Bureaucracy vs. space > Agreed, but Henry's original posting was comparing shuttles with cargo > planes, not with expendables. True, but it doesn't affect my point, which is that the cargo environment for the shuttle is not severe enough to explain the massive difference in paperwork. > ... it is perfectly > reasonable for those regulations to be stricter than for expendables, > given that the shuttle is manned, reusable, and more delicate than an > expendable. Sure. But several orders of magnitude? The Hercules is also manned and reusable, if a bit more durable. By the way, I think you're overestimating the robustness of expendables; no space-launch system is made any heavier than it absolutely needs to be. If anything, the shuttle has to be more robust than expendables. > As for being manned, it doesn't matter how much risk the astronauts are > willing to take for the glory of NASA. Every manager or engineer on > the ground still is morally required to worry about their safety --- > much, much more than what he would be expected to worry in the case of > an unmanned vehicle. The same comment applies to airlines. They seem to find it possible to fly cargo and people at reasonable costs with reasonable paperwork... but then, they have incentive. They have to be useful, or they go broke. > As for reusability, in an expendable launch the only party who really > needs to worry about payload safety is the payload owner, since he is > the only one who stands to lose in case of an accident... Ho ho. Sorry, wrong. The launcher supplier has to worry about the effects of a failure on future business. This is *not* a trivial issue, especially with production volumes as low as they are today. (That is, he can't just say "well, we had a failure, but with 357 successes in the last three years, we can quite safely say that it was a fluke and our booster is still amply reliable". The airliner builders have a bit of an advantage here.) At the very least, the launch outfit has to have iron-clad proof that the failure was the satellite's fault, and that's not easy to get. The Soviets might have commercial Proton business by now if they hadn't had those failures. With volume so low and costs so high, it doesn't take many failures for customers to decide that your launcher is jinxed. Expendable builders get to worry a lot about payload safety. However, unlike NASA, they do have to be useful, so they have some incentive to keep things under control. -- "For perfect safety... sit on a fence| Henry Spencer @ U of Toronto Zoology and watch the birds." --Wilbur Wright| {ihnp4,decvax,uunet!mnetor}!utzoo!henry ------------------------------ Date: 1 Jun 88 20:07:00 GMT From: kenny@m.cs.uiuc.edu Subject: Mir elements, epoch 25 May Satellite: Mir Catalog id 16609 Element set 212 Epoch: 88144.82886303 Inclination: 51.6140 degrees RA of node: 192.4097 degrees Eccentricity: 0.0022899 Argument of perigee: 5.3494 degrees Mean anomaly: 355.2223 degrees Mean motion: 15.75455582 revs/day Mean motion acceleration: 0.00019094 * 2 revs/day/day Epoch Revolution: 12999 Semimajor axis: 6721.43 km Apogee height*: 358.66 km Perigee height*: 327.88 km Source: NASA Goddard via T.S.Kelso's `Celestial RCP/M' * Apogee and perigee altitudes are referred to the mean radius of the Earth (6378.15 km), and not to the local radius of the geoid. They are only approximate, and should not be used for orbit prediction. ------------------------------ Date: 1 Jun 88 20:16:00 GMT From: kenny@m.cs.uiuc.edu Subject: Re: Mir elements, epoch 25 May Sorry about the delay on this posting; I was in Denver for the National Space Society convention. During the convention, I observed Mir visually twice, on Saturday and Sunday evenings. Since it arrived exactly when predicted (+/- a few seconds, perhaps) I surmise that as of Sunday night, 10:20pm MDT, the Soviets had not yet reboosted and dumped Progress 36. One may expect that they will in short order, as they plan to launch a visiting Soyuz this week and will need to clear the rear docking port of Kvant to accomodate it (The side ports cannot be used until the first Star module with a remote manipulator system is on-orbit). Kevin Kenny UUCP: {ihnp4,pur-ee,convex}!uiucdcs!kenny Department of Computer Science ARPA: kenny@M.CS.UIUC.EDU University of Illinois 1304 W. Springfield Ave. Urbana, Illinois, 61801 Voice: (217) 333-6680 ------------------------------ Date: 24 May 88 04:12:15 GMT From: nfsun!ditka!formtek!darth!pitt!cisunx!bgarwood@uunet.uu.net (Robert Garwood) Subject: Re: Space Station Names In article <8552@ames.arc.nasa.gov> mike@ames.arc.nasa.gov.UUCP (Mike Smithwick) writes: >And now the question you've all been staying up late for: what the >heck are they going to name the Space Station?? How about just painting it white with the following in large black letters : "Space Station" Why pay more for a brand name when generic will do? Bob Garwood "I don't have a .signature file." ------------------------------ Date: 22 May 88 22:37:36 GMT From: kr0u+@andrew.cmu.edu (Kevin William Ryan) Subject: Re: Space Suits Someone mentioned the 'skin suit' style space suit, and asked for some references. Enjoy them courtesy of J.E. Pournelle, in Vol. 2, No. 3 of the now defunct _Destinies_. NASA Report CR-1892, Development of a Space Activity Suit, by James Annis and Paul Webb. Ask your congresscritter, and he should send you one - that's how I got my copy (since misplaced in one of my moves...). The suit is basically a multilayer (seven in this version) tight leotard. Pressure maintained is ~170 torr around the torso, tapering to ~100-120 torr at the extremities. Multiple layers are preferable for ease of construction (one layer is not required to support all that pressure), ease of tailoring, and of course redundancy. Pressure integrity is kept around the head by a bladder extending over the torso, providing constant volume while inhaling. Cooling is provided by sweat (quite efficient cooling, what with instant evaporation). Loss of several pints expected in average EVA. Heating was planned by electrical resistance heaters in on oversuit - said oversuit also to provide radiation and thermal protection. Dexterity in the test suits was far far superior to the existing semi-hard suits. (Interesting parts included 'rounders' where the human body had concavities and flats, such as the backs of the hands, in order to allow the suit to exert pressure.) Estimated cost for the seven layer suit, including silk underlayers for ease of donning was $2000 1974 dollars, compared to the rather extreme cost of period and present suits. Present shuttle suit costs ~$200K. Difficulties included _individual_ tailoring, including a need for a new suit if the owner changed weight by more than a few pounds, and the task of putting on seven layers of _tight_ leotards. Note also the low pressure in the suit, 170 torr compared to the present shuttle pressure of 760 torr, which may require compression - decompression cycles. Tailoring and donning problems were expected to be reduced with more experience, plus some work on user- friendly zipper pull handles. The overall design was thus a multilayer leotard, oxygen tank, battery and radio backpack, covered by a heavy silvered coverall with sweat vents. Very light, cheap, and providing (compared to any other design) incredible freedom of movement. Also a large safety margin - a tear would simple cause pain, swelling, and edema (sp? Swelling of the skin due to vapor pressure of under- lying fluids.). Not instantly fatal decompression and loss of suit enviornment unless the helmet or torso bladder are ruptured. An excellent design. NASA never picked up on it for reasons completely unknown to me. Perhaps somebody was instinctively repelled by the thought of expensive astronauts floating around in expensive skivvies?... kwr "Jest so ya know..." ------------------------------ Date: Thu, 02 Jun 88 00:04:24 -0900 Reply-To: Sender: From: Scott Dennis, Computer Support Subject: RE: SPACE Digest V8 #240 Well, then she was probably pretty lucky! Darn cars don't even see motocycles.. Well, I'm hittin' the hay. I'll see you in the morning at about 10, then! ------------------------------ Date: 26 May 88 17:39:43 GMT From: hall!pai!erc@umn-cs.arpa (Eric Johnson) Subject: Re: Naming the space station. In article <12487@shemp.CS.UCLA.EDU>, cc1@CS.UCLA.EDU writes: > How about "Fred"? > > --Net.Rabbit Count mine as another vote for Space Station Fred -- Eric F. Johnson | Phone +1 612-894-0313 | Are we Prime Automation,Inc | UUCP: ihnp4!umn-cs!hall!pai!erc | having 12201 Wood Lake Drive | UUCP: sun!tundra!pai!erc | fun Burnsville, MN 55337 USA | BIX: erc | yet? ------------------------------ Date: Thu, 2 Jun 1988 14:40-EDT From: Dale.Amon@h.gp.cs.cmu.edu Subject: Re: Nuclear bombs I'd also suggest those interested dig through back issues of Life, around 1959-61 for a picture of a hole in the ground in a Carolina farm field after it was accidentally dropped from a B-52 or B-57. Triggers made a good size crater and caused some local cleanup problems, but the last time I drove through the Carolina's they were quite well populated... ------------------------------ Date: Thu, 2 Jun 88 14:40:33 pdt From: Eugene N. Miya Subject: Tours of NASA Ames during Usenix I go on vacation and my mailbox, etc. fills. gezz.... Several of you have written to tell me you would like tours of the Ames Research Center while you are visiting SF during Usenix. Contrary to popular belief, my job isn't to read mail and news, I am supposed to be doing development and research. I wish I could really help a lot of you, but it's too short a notice for me to do anything with a large group of you. It's not clear to me that I will be going to Usenix for more than an a day (there's just not that much on the program to interest me). I've also been asked to convey a NASA Internal Unix User Group meeting, so this puts severe time contraints on me. If you guys had suggested this 6 months ago... Actually, Ames is pretty boring stuff, no mission controls, no high performance aircraft (well, a couple of Harriers, F-104s and T-38s). Tours are only given during daylight (working hours) on strict time schedules. FOREIGN NATIONALS TAKE 1 week to 1 month to clear in advance since this is a Government reservation, this includes English speaking nations (sorry Bob and others). So I have to turn you guys down in a blanket way, there's just too many of you on too short a notice. Now if you win a Field's or Nobel Prize, and you have time to stop by to give a talk, I'm sure they can make exceptions for you. Next conference, have the local arrangements communittee reach by 6 months in advance. Contact the Public Information Office (get the phone as a exercise for the reader [remember this one?]) if you still want to try, we are 40 minutes South of SF on 101 (terrible drive during rush hour) it's the Moffett Field exit (the first street exit after Stierlin [Silicon Graphics and E&S and Pyramid, and Bridge?] and Rengdorff [ SUN Microsystems]. Another gross generalization from --eugene miya, NASA Ames Research Center, eugene@aurora.arc.nasa.gov resident cynic at the Rock of Ages Home for Retired Hackers: "Mailers?! HA!", "If my mail does not reach you, please accept my apology." {uunet,hplabs,ncar,ihnp4,decwrl,allegra,tektronix}!ames!aurora!eugene "Send mail, avoid follow-ups. If enough, I'll summarize." ------------------------------ Date: Thu, 2 Jun 88 14:37 AST From: Subject: Space Digest Please send me Space Digest Volume 8, Issue 230. Thank you. gf ------------------------------ Date: 2 Jun 88 14:48:17 GMT From: mtunx!whuts!sw@rutgers.edu (WARMINK) Subject: skin tight space suits All this discussion about the skin-tight pressure suits reminds me of the suits worn (?) by the adventurous space men & women on the covers of those old science fiction magazines... -- ------------------------------------------------------------------------------ "Please continue the petty bickering, | Stuart Warmink, APT UK Ltd. it is most intriguing" Cmdr. Data | !whuts!sw, Whippany NJ USA -----------> My opinions are not necessarily those of APT UK Ltd. <----------- ------------------------------ Date: 2 Jun 88 14:58:16 GMT From: mtunx!whuts!sw@rutgers.edu (WARMINK) Subject: Re: Some more launch loop stuff... In article <1703@looking.UUCP>, brad@looking.UUCP (Brad Templeton) writes: > > What ever happened to the good old fashioned 500 mile linear acellerator? > At 3.5g for 3 minutes 20 seconds you hit orbital velocity. > You have to correct to circular with a reaction rocket later of course, > and you have to also get back the velocity you lose to air. Don't forget about air resistance - quite substantial at orbital velocity and near sea level, not to mention the frictional heating effects! -- ------------------------------------------------------------------------------ "Please continue the petty bickering, | Stuart Warmink, APT UK Ltd. it is most intriguing" Cmdr. Data | !whuts!sw, Whippany NJ USA -----------> My opinions are not necessarily those of APT UK Ltd. <----------- ------------------------------ End of SPACE Digest V8 #265 *******************