Date: Mon, 24 May 93 05:05:35 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #618 To: Space Digest Readers Precedence: bulk Space Digest Mon, 24 May 93 Volume 16 : Issue 618 Today's Topics: About the mercury program Adaptive Optics Boeing TSTO concept (sort-of long) (2 msgs) ELEVEN G-forces during atmospheric reentry??? (3 msgs) Hey Philly! Re: Why Government? (2 msgs) Hey Sherz! (For real!) Cost of LEO (3 msgs) Moon Base (2 msgs) Post Doctoral Position at NASA Soyuz and Shuttle Comparisons 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: Mon, 24 May 1993 00:40:13 GMT From: Leigh Palmer Subject: About the mercury program Newsgroups: sci.space In article <1993May22.161634.5931@ke4zv.uucp> Gary Coffman, gary@ke4zv.uucp writes: >I think it's wrong to blame the astronaut for this failure, at least not >totally. Instead the PI screwed up in mechanical design. A look at his >3 year old's Jack in the Box would have showed him how to make a box with >a hand crank that even the clumsiest little vandal couldn't easily break. A real apologist for the astronaut! Do you suppose he broke the handle in rehearsal? Is it possible he didn't rehearse? Would it have been wise for him to have rehearsed? Leigh ------------------------------ Date: Sun, 23 May 1993 18:48:27 GMT From: Frank Crary Subject: Adaptive Optics Newsgroups: sci.space,sci.astro In article Bob_Hearn@qm.claris.com (Robert Hearn) writes: >> Instead of using natural reference stars, could lasers be used >> by scattering the beam off of the sodium layer in the upper >> atmosphere, etc. , to act as an artifical reference star? >I thought that was how professional adaptive optics systems worked. >Could someone familiar with the techniques please post a general >description of them? They usually switch to a bright, near-by reference star (usually by moving the secondary mirror very slightly...), calculate the corrections necessary to resolve the reference as a point, then switch back to the dim object to be observed. For the near IR the reference star has to be re-observed and the corrections re-calculated at least every tenth of a second. As you move to shorter wavelengths more frequent cycling is required and therefore the reference star has to be closer to the observed object. At some point this falls apart, since you can't count on finding a sufficiently bright reference star within (say) ten or twenty arc seconds of whatever you want to observe. Artificial guide stars let you create a reference where ever you like. Unfortunately, for large telescopes, the artificial reference is relatively close to the telescope (i.e. not in the far-field) and the required calculations become more difficult... >There's actually an adaptive optics system available to amateurs: the >AO-2. It steals half the light going to the eyepiece with a beam- >splitter, and adjusts the angle of a lens or prism to keep the >brightness equal in all four quadrants, thus keeping the image of >a planet or bright star centered. Doesn't work for deep-sky objects, >though. Also, I get the impression that it doesn't really correct for >atmoshpheric turbulence, just telescope instability. It doesn't correct for blurring due to turbulance, but if you have really poor seeing, the large-scale turbulance can also move the image around. However, for the big, professional telescopes this isn't a very usefull technique: They generally have very good seeing... Frank Crary CU Boulder ------------------------------ Date: Sun, 23 May 1993 22:23:24 GMT From: Henry Spencer Subject: Boeing TSTO concept (sort-of long) Newsgroups: sci.space In article <1to6bu$bvf@access.digex.net> prb@access.digex.net (Pat) writes: >>... a better trick: inject liquid hydrogen (I think >>it was) into the bypass ducts of the regular 747 engines, and burn it... > >I guess that makes Nitrous injection look pale :-) How would this >differ from a conventional afterburner? ... The main difference is that the air stream in question has not gone through the engine core; this is its only exposure to fuel. The boundaries are admittedly rather fuzzy, since there are afterburning turbofans that use both the core flow and the duct flow in their afterburners (although they generally have rather low bypass ratios, hence are a different sort of animal). >If they seriously boost thrust, did they have to rre-design >the thrust pylons? I'd expect so, but I didn't see technical details. -- SVR4 resembles a high-speed collision | Henry Spencer @ U of Toronto Zoology between SVR3 and SunOS. - Dick Dunn | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Sun, 23 May 1993 22:25:57 GMT From: Henry Spencer Subject: Boeing TSTO concept (sort-of long) Newsgroups: sci.space In article <1to6kj$csu@access.digex.net> prb@access.digex.net (Pat) writes: >|The B-58 wasn't capable of Mach 3 even in a dash, and neither the SR-71 >|nor the X-15 was made of aluminum... > >How about the XB-70? The XB-70 forward fuselage was titanium, and the main body and wing were stainless-steel honeycomb (an excellent material, but fearfully expensive to make and use -- the two XB-70s cost their weight in gold). -- SVR4 resembles a high-speed collision | Henry Spencer @ U of Toronto Zoology between SVR3 and SunOS. - Dick Dunn | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 23 May 1993 20:01:28 GMT From: Claudio Oliveira Egalon Subject: ELEVEN G-forces during atmospheric reentry??? Newsgroups: sci.space A friend of mine has written that Gus Grinson, during his suborbital flight of the Mercury program, was subjected to acelerations from 0 to ELEVEN g's, within 32 seconds, when he was reentring the atmosphere!!! Although I can not recall the phisiological tolerance to g-forces 11 g's seems darn too high for me. Most likely it is well above the value that anyone can tolerate. So my questions are: 1) What is the g interval that a human being can tolerate and 2) What was the maximum acceleration that a Mercury astronaut was subjected to. C.O.Egalon@larc.nasa.gov Claudio Oliveira Egalon ------------------------------ Date: Sun, 23 May 1993 22:58:15 GMT From: Henry Spencer Subject: ELEVEN G-forces during atmospheric reentry??? Newsgroups: sci.space In article <1tol6oINN1et@rave.larc.nasa.gov> C.O.Egalon@larc.nasa.gov (Claudio Oliveira Egalon) writes: >A friend of mine has written that Gus Grinson, during his >suborbital flight of the Mercury program, was subjected to >acelerations from 0 to ELEVEN g's, within 32 seconds, when >he was reentring the atmosphere!!! Yup. The suborbital trajectories of the Mercury-Redstone flights involved rather higher decelerations than the orbital flights, because the capsule entered thicker atmosphere sooner. Ham took 14.7G, and both Shepard and Grissom took nearly 12. The Mercury seat design was tested to 20, in a centrifuge, by Carter Collins. (Although the Mercury, and later, orbital flights generally involved no more than 6-7G on reentry, some classes of mid-launch aborts could have involved rather higher decelerations.) >1) What is the g interval that a human being can tolerate and It depends on duration, direction, support, training, etc. Also on whether it is necessary for the human to continue functioning and/or stay conscious during the acceleration. "Bioastronautics Data Book" (NASA SP-3006) has a number of graphs showing various possibilities. Notably, if you're willing to pick a good case -- highly-motivated test pilots with major high-G experience, on their backs, well supported -- then two minutes at 14G is neither dangerous nor incapacitating. With extreme measures (water immersion), over 30G is tolerable for maybe fifteen seconds. And we're still talking about what people will *voluntarily tolerate*, as opposed to surviving in a life-threatening emergency... although in fact the numbers above are pushing close to the "probable injury" levels, so accelerations much beyond these are dangerous. (Impact accelerations -- endured for only a fraction of a second -- are a very different story, with much higher limits. The limit of survival for impact is circa 175-200G.) -- SVR4 resembles a high-speed collision | Henry Spencer @ U of Toronto Zoology between SVR3 and SunOS. - Dick Dunn | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: Mon, 24 May 1993 02:38:32 GMT From: Dave Michelson Subject: ELEVEN G-forces during atmospheric reentry??? Newsgroups: sci.space In article henry@zoo.toronto.edu (Henry Spencer) writes: >>A friend of mine has written that Gus Grinson, during his >>suborbital flight of the Mercury program, was subjected to >>acelerations from 0 to ELEVEN g's, within 32 seconds, when >>he was reentring the atmosphere!!! > >Yup. The suborbital trajectories of the Mercury-Redstone flights involved >rather higher decelerations than the orbital flights, because the capsule >entered thicker atmosphere sooner. Ham took 14.7G, and both Shepard and >Grissom took nearly 12. The Mercury seat design was tested to 20, in a >centrifuge, by Carter Collins. > >(Although the Mercury, and later, orbital flights generally involved no >more than 6-7G on reentry, some classes of mid-launch aborts could have >involved rather higher decelerations.) During the Soyuz 18-A abort in April 1975, Lazarev and Makarov pulled about 15 g's. Since the flight lasted 21 minutes and 27 seconds, the Soviets now hold the record for the longest suborbital mission flown. -- Dave Michelson -- davem@ee.ubc.ca -- University of British Columbia ------------------------------ Date: Sun, 23 May 1993 16:41:46 GMT From: "Phil G. Fraering" Subject: Hey Philly! Re: Why Government? Newsgroups: sci.space,talk.politics.space khayash@hsc.usc.edu (Ken Hayashida) writes: >pgf@srl01.cacs.usl.edu (Phil G. Fraering) writes: >I had originally posted: >>>BTW, I'm not republican (as someone seemed to infer). I'm a conservative >>>democrat. Don't misconstrue my arguments, I'm for space shuttle because >>>its the most sophisticated and best example of American technology in the >>>air-space field. >Philly wrote: >>Tell a lie often enough, and maybe someone will beleive it... >I hope you aren't calling me a liar, but then again you probably would >resort to name-calling instead of focusing on issues. This only >shows how weak your arguments are. Uh, no. Let me put it this way: the shuttle, as a system, is composed of subsystems: the propulsion system, thermal protection system, life support system (including power), guidance system... any major systems that I've missed? I will now jot down the sub-subsystems, prior to listing the "lineage" and technological development in each of them. Propulsion system: three subsystems here: solid rocket boosters, SSME's, and OMS/RMS system. Thermal protection system: tiles and thermal blankets Guidance systems: no subsystems here... life support: LiOH cartriges, food, toilet, fuel cells (for power and water). Okay, now the detailed criticism: 1. Propulsion: A. Solid Rocket Boosters: these aren't really advanced technology. They are a simple scale-up of the segmented boosters used on the Titan well before the Shuttle came along. The fact that they are segmented, along with their high vibration loads, would be proof that they shouldn't be used further in any advanced launch system. i. The Titan III was once considered for use as a manned booster, but the vibration caused by the SRB's was considered to be counterproductive to man-rating. (Hey, anyone have a source for this? I remember reading it somewhere...) ii. The nature of the segmented boosters is such that they are not only expensive to build and/or refurbish, but they remain of dubious safety. They have caused the only loss of life and orbiter to date (unless you want to count the Enterprise, but that's another story where I have heard conflicting stories from people I trust. Maybe someday I'll ask Mary Shafer about it). And NASA's safety inspection procedures haven't improved much since then, if you believe the story about the pliers. iii. Attempts to "fix" the SRB's with a new design are turning out to be of such expense that it is surviving on pure pork-barrel momentum. The ASRM (sort of a contradiction in terms) will allow, after some 12 years of operation, the STS system to finally carry its design payload, but only if in the case of an emergency landing you plan to rebuild the orbiter or write it off, because it's over the max recommended safe landing weight. B. Space Shuttle Main Engines: in _"What do *You* Care What Other People Think?"_ (book titles should be underlined, but said title already includes an underline and quotes, so it looks awkward) by Richard Feynmann, in the chapter "Fantastic Figures." A lot of the criticisms of the shuttle program in that book unfortunately still seem to be relevant. Like the pliers, which according to the signatures of three separate people, had been removed. Perhaps more relevant is the fact that of launcher designs currently being proposed, they are either not using the SSME or are using a derivative with greatly downgraded performance in the hope that it will be reliable. C. OMS/RCS system: It just works. But aside from slightly better electronics, there's nothing really different about this than the one on the Service Module... other than the different thruster configuration needed to accomodate the aerodynamics of the shuttle. While it's a good workhorse system, it isn't very advanced compared to the Hubble's attitude control system. Perhaps this is a good lesson: the "least advanced" system is giving Yeoman sevice... 2. Guidance systems: these were just upgraded; hardware considered by NASA as being "cleared" for space use are usually much less powerful or up-to-date than those in other fields, or many computers flying in space right now (I think the Hubble has more advanced computers; its guidance needs, though, are much more demanding). 3. Life support: A. The LiOH cartridges are I believe much the same (except for minor improvements) as those used in Apollo, and different from those planned for the station. (At one point they were going to use something really advanced for the station, but they backed down; maybe this'll change in the redesign process _or_ after they get a couple modules up and find out it doesn't take hundreds of millions of dollars to install a couple lab racks with recycling equipment). B. Food: I don't think this is much different from Skylab food. C. Toilet: same design as Skylab, except more costly and less reliable. D. Fuel cells: these don't really do much that the Apollo ones didn't, except for the need to provide power to control the aerodynamic surfaces on the way down. They have _no_ relevance to the future needs of space exploration because they're just an expendable short-time- period power source. If the shuttle had good solar cells, that would be a different story; but since it's meant to be a launcher and not a station, this is beginning to get ridiculous. I will now procede to the rest of Ken's article. >I had written: >>>shuttle is the best piece of hardware we've got. If shuttle haters get >>>their way, we'll be out of the manned space business for the rest of the >>>century. boy (smirk), that'd be a great legacy wouldn't that? >>>Back to the days of 1976-1979 when skylab fell and shuttle couldn't fly. >>>Carter administration II...hope not! >>We're out of the manned space exploration business now; have been since >>1973. Where the hell were you? >Gee, need I write more folks? I must've hit pretty close to home or >something... No, I'd just like to point out that the last lunar mission that the U.S. has launched, and the last manned space exploration mission, was launched on Dec. 7, 1972. (I guess I was wrong about 1973). Since then, we've just been screwing around in Low Earth Orbit. Maybe this is grounds for letting December 7 reclaim the title of "day of infamy" from November 7. You did cut close to the bone about manned exploration there, because it does cause me great pain that we haven't done anything for so long. > have a nice day philly. Try writing a long reply at 1200 baud in emacs that the original poster won't read and see how fun your day gets. But don't worry, dear, I'll try to have a nice day anyway. The least you could do to help is to read and re-read this post all the way through a couple times. It was tedious to write. And the next time you go home to visit your Ma, try making a side trip up to the Keck telescope and look at it for a while. And also look at the pricetag while you're at it. Can you think of any single shuttle mission that's provided as much science return as the Keck is likely to? (Yes, I'm comparing apples and oranges, but when oranges cost a hundred times as much as apples, you learn to make do with apples and the occasional pinch of lemon juice for vitamin C). I wrote that to impress on you the difficulty I've had trying to convince people much smarter than me about the validity of the space program itself. The Shuttle program has apparently convinced them that there's really nothing there. I'm sure you're a nice, interesting boy, but you don't know how absurd some of your arguments have sounded. Such as the one where the shuttle is a better system than others because it used _more_ manpower than other alternative systems. This is close to the inverse of the definition of efficiency in engineering (although I may have to bring Dan Stephenson in on this argument before I'm through). That's all I have to say for now, but if I have to say it again I may just repost this again. Unless you can really answer the points outlined above. Which you haven't yet. Later, Phil -- +-----------------------+---------------------------------------+ |Phil Fraering | "...drag them, kicking and screaming, | |pgf@srl03.cacs.usl.edu | into the Century of the Fruitbat." | +-----------------------+-Terry Pratchett, _Reaper Man_---------+ ------------------------------ Date: Sun, 23 May 1993 18:38:27 GMT From: "Phil G. Fraering" Subject: Hey Philly! Re: Why Government? Newsgroups: sci.space,talk.politics.space And I forgot to comment on the thermal protection system. Part of the pitfalls of the narrow window I'm looking through as I'm writing this. Anyway, most if not all currently proposed launch systems that have a return element don't rely on shuttle technology for their thermal protection. Although the HL-20 might use it... (I'd like to comment that although it seems to be a dead end, the tile system on the Shuttle has given the least problem of any of its components, even though Sixty Minutes was running reports that the tiles were all going to unzip upon re-entry or something like that). -- +-----------------------+---------------------------------------+ |Phil Fraering | "...drag them, kicking and screaming, | |pgf@srl03.cacs.usl.edu | into the Century of the Fruitbat." | +-----------------------+-Terry Pratchett, _Reaper Man_---------+ ------------------------------ Date: 23 May 1993 14:42:56 -0400 From: Pat Subject: Hey Sherz! (For real!) Cost of LEO Newsgroups: sci.space Ken, you are mixing your measures, for cargo. For the saturn, the point was to deliver the S-IV, the CSM/LM to stable orbit. Look at the skylab mission. THe S-V, delivered the WOrkshop to Stable High ORbit. Other proposed Apollo applications were to deliver Large quantities of stuff to orbit. In the SHuttle, you can only count, the Payload Cargo, and the MidDeck, flight compartment mass plus the RObot Arm, as delivered Payload. If you want count abou;t 10 % of the Orbiter weight as useful payload to orbit. THe return system, is not useful orbital payload. Now in Shuttle C, the entire Canister payload is working cargo, or in the SSF option C baseline, the worksop is cargo. For a return system, it's not. Think of it as a semi-trailer. the trailer is canister, the Cargo is weight, the tractor is necessary to get from A to B. If you intend to climb steep terrain, you need a much different tractor, but the useful payload is still just the cargo delivered. Look at a train, or a ship. If a ship has to cross a shallow harbor, it can only carry a reduced cargo. No matter if it's a ULCC, if it can only draft 27 feet, that's the useful cargo delivered. Look at a shuttle TDRSS mission, sevarl million pounds at the pad, go to putting appx 2 K lbs to GEO. that's the delivered useful cargo. Or in LEO terms, it's a TDRSS and a PAM? A Delta will meet that same cargo lift. pat ------------------------------ Date: 23 May 1993 14:54:06 -0400 From: Pat Subject: Hey Sherz! (For real!) Cost of LEO Newsgroups: sci.space >In article <1tn3f7$e4o@hsc.usc.edu> khayash@hsc.usc.edu (Ken Hayashida) writes: >>(although some still refuse to acknowledge >>the feats performed by the shuttle). Ken I know a guy who's so flexible he claims he can auto-fellate himself. Now while this is a truly amazing feat, I don't see how relevant it is. Many of the things you point out as Amazing are essentially technical side shows. The Main Event is still the Three ring circus. What we need is Rapid, Reliable, Economical Medium lift to LEO. And for all the money the SHuttle has eaten, we have lost capcbility. Where is the money for Basic High speed Research? Advanced Suit Technology? Closed Cyucle Life SUpport? Methane fuel production? Advanced Propulsion? Engineering Qualification programs? Relative to the money spent, the catalog of Space QUalified hardware is pathetic. Your'e a doctor. How would you feel if NIH and the Entire Bio-medical establishment with all the research and commercial dollars poured in, only delivered 1 new procedure a year, and one new drug, and that procedure costs more then the old procedure and is more dangerous, and the drug is more expensive, and you have to request an ampoule 6 months in advance? pat ------------------------------ Date: Sun, 23 May 1993 21:05:49 GMT From: Josh Hopkins Subject: Hey Sherz! (For real!) Cost of LEO Newsgroups: sci.space khayash@hsc.usc.edu (Ken Hayashida) writes: >My calculation was: >>>STS/shuttle mass to orbit: >>>Mass of the orbiter plus payload in the bay. >Allen sez: >>The mass of the orbiter is a pointless thing to consider. A launcher which >>lifted a million pounds to LEO but only one ounce of payload would win >>your contest but would be a pretty useless operational launcher. >... >>The only figures of merit are capability and cost. >I agree that capability and cost are important. but, I disagree with >your methodology. ... >If I really wanted to limit the discussion to payload, I could >have counted the Command Module as the ultimate payload of the Saturn V! >Clearly that is incorrect. so, the basis of my decision to include the >orbiter's mass in the mass to LEO calculation is based on inclusion of the >total mass injected into orbit by the launch system in question. What I believe you should be trying to measure is payload. This has nothing to do with the mass of the vehicle. A one million pound experimental SSTO with no payload would, under your accounting scheme, have a huge mass to orbit and a huge mass returned. It would not, however, be any use to anyone. In addition, to do an accurate calculation of the type you are considering is going to be very complex. Many ELVs leave an upper stage in orbit, often partially fueled. To calculated the total mass thrown into space you are going to need to track down lots of numbers. >The S-V vehicle put up the whole S-IV-B stage plus the LEM-CSM-escape tower. The escape tower was ejected a little more than three minutes after launch. It cannot be considered payload to orbit. >If all of those pieces are gonna get talleyed into the S-V mass to orbit >figure, why shouldn't the orbiter's mass be talleyed in to LEO calc? The question is slightly complicated by the fact that the S-IVB stage was fired to finish orbit insertion, but was also used to leave orbit. If you want payload capability, I would use the mass of Skylab. If you want actual mass inserted into orbit, you are going to have a very messy calculation on your hands, as you will need to take into account part of the mass of the S-IVB stage and different masses of the lunar vehicles. -- Josh Hopkins jbh55289@uxa.cso.uiuc.edu "This Universe never did make sense; I suspect it was built on government contract." -RAH ------------------------------ Date: Sun, 23 May 1993 21:25:24 GMT From: Nick Janow Subject: Moon Base Newsgroups: sci.space henry@zoo.toronto.edu (Henry Spencer) writes: > The main reason for going back to the Moon is to start a sustained program > of space exploration. Well, that supports the case for an aluminum-oxygen extraction plant on the moon. It supports further projects, and the officials who approved it would try to encourage use of it, to justify their decision. :) The R&D in automation/remote-operation would be applicable to civilian use on Earth too. It could greatly increase industrial productivity. -- Nick_Janow@mindlink.bc.ca ------------------------------ Date: Mon, 24 May 1993 00:00:36 GMT From: Nick Janow Subject: Moon Base Newsgroups: sci.space gary@ke4zv.uucp (Gary Coffman) writes: > I've been on the other side of this with Nick, but comets and Earth > crossing asteroids may offer much higher commercial rewards. And open space > offers commercial potential for communications, manufacturing, and perhaps > even power. What's Luna offer? Maybe He3, some light metals and oxygen > buried in yet another gravity well. Not very appealing. The moon offers easily available metal and oxygen ores and a gravitational field, and is nearby (short communication times and within manned reach). It would probably be cheaper and easier to develop a resource extraction facility there than to develop zero-g facilities for extracting water from near-Earth asteroids. The technology and facilities developed with a lunar base project would greatly reduce the cost of developing open-space projects. It would be a more gradual development; technology in small steps, rather than one risky leap. A mining company would probably choose a lower-grade ore body in a temperate, developed area rather than a higher-grade one in Antarctica, where they'd face new problems (redesigning equipment for extreme cold) and the hassle of time delays (no FedEx overnight delivery). For similar reasons, I do think that although asteroids will eventually be a cheaper source of resources than the moon, they would not be at this time. Lunar bases don't make economic or > scientific sense, and they aren't *necessary* stepping stones to the more > interesting targets. They aren't *necessary*, but they could make economic and scientific sense. Studying "dead bones" provides a lot of critical information for studying living animals. Without the study of fossilized remains, scientists might still be studying existing life forms from an incorrect perspective. Likewise, studying the "fossilized bones of the solar system" (the moon), might provide useful insights into processes on Io, Venus, etc. BTW, can you provide a list of "interesting" targets in a list that everyone can agree on? :) To put it simply, the moon project might be feasible to get money for. The asteroid one--needing more money and requiring more new technology--might not be. -- Nick_Janow@mindlink.bc.ca ------------------------------ Date: 23 May 1993 20:24:19 GMT From: Claudio Oliveira Egalon Subject: Post Doctoral Position at NASA Newsgroups: sci.space > on the possiblity of an overseas post-doc position at NASA > (or other US space related research centre). That is not the first or second time that such a question comes along... Shouldn't we write a FAQ about that??? The National Ressearch Council, NRC, has a Post-Doc fellowship that you can use at any NASA Center as well as many other companies and, I guess, even Universities. Try contacting the NASA Center that you are interested to work for they have all the information that you need to apply for this Post-Doc fellowship. Non-citizens are require to come to work under a "J" VISA, but if you already have a green-card (which is no longer "green" but "pink"), you do not have to worry about that... C.O.Egalon@larc.nasa.gov Claudio Oliveira Egalon ------------------------------ Date: 21 May 93 13:43:00 From: David.Anderman@ofa123.fidonet.org Subject: Soyuz and Shuttle Comparisons Newsgroups: sci.space In your message you stated that: The Soyuz-TM spacecraft is lifted into orbit by PROTON, which has some fairly impressive heavy-lift capabilities. The PROTON was used to loft the MIR main core module, which weighed 21 tons, the KVANT 1, KVANT 2, and KRISTAL modules into orbit. Here are the specs: First Stage Engine RD-253 Propellants Nitrogen Tetroxide/UDMH Thrust 167 tons Actually, the Soyuz TM is launched by a rocket called the Soyuz rocket. The Proton is about three times more powerful than the Soyuz rocket, and was originally used to launch a satellite called the Proton. BTW, the Rd-253 engines were uprated to 178 tons of thrust about 10 years ago..... --- Maximus 2.01wb ------------------------------ Date: 23 May 1993 23:04:02 GMT From: Timothy Banks Subject: Why Government? Re: Shuttle, "Centoxin" Newsgroups: sci.space,talk.politics.space In article <1tiqpo$o89@access.digex.net> prb@access.digex.net (Pat) writes: > >New Zealand, Australia, and the Philippines did not pay for >their defense either, but their economies are in the S***TEr. > Pat - go read a history book, will you? The above statement betrays terrible ignorance....and is insulting to the many who died. A little bit of current affairs might be nice too. -- Timothy Banks, Physics Department, Victoria University of Wellington, NZ. bankst@kauri|rata|matai.vuw.ac.nz, banks@beagle.phys.vuw.ac.nz. "He's dead, Jim!" "OK, you take the tricorder, I'll take the wallet!" ------------------------------ End of Space Digest Volume 16 : Issue 618 ------------------------------