Date: Sun, 2 May 93 05:26:05 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V16 #508 To: Space Digest Readers Precedence: bulk Space Digest Sun, 2 May 93 Volume 16 : Issue 508 Today's Topics: Deployable Space Dock.. Galileo Update - 04/29/93 Gamma Ray Bursters. WHere are they. Gamma Ray Bursters How energetic could they be? HST Servicing Mission Scheduled for 11 Days (2 msgs) Internet resources (2 msgs) JPL Info Summary/"Our Solar System at a Glance" [Part 2] Long term Human Missions Private Support of Exploration (Russian America) Satellite around Pluto Mission? Space Manuevering Tug (was HST servicing mission_) (2 msgs) Statement by NASA Administrator Daniel S. G Teflon Development. 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: Fri, 30 Apr 1993 08:00:50 GMT From: nsmca@acad3.alaska.edu Subject: Deployable Space Dock.. Newsgroups: sci.space Idea for repair of satellites: Warning I am getting creative again: Why not build a inflatable space dock. Basically deploy one side of the space dock (using a scissor shaped structure, saw it on beyond 2000), then maneuer the side to next to the satellite and then move the rest of the dock around the satellite and seal it.. The inflate the dock with a gas (is does not have to be oxygen, just neeeds to be non-flameble, non-damaging to the satellite and abel to maintain heat), thenheat the space dock (for the astronaut who will be working onthe satellite to be able to not have to wear the normal bulky space suit, but a much striped down own).. I know this might take a slot of work or not??? Or just to plain wierd, but ideas need to be thought of, for where is tomorrow, but in the imagination of the present.. == Michael Adams, nsmca@acad3.alaska.edu -- I'm not high, just jacked ------------------------------ Date: Fri, 30 Apr 1993 01:46:53 GMT From: The Arch-Deviant Subject: Galileo Update - 04/29/93 Newsgroups: sci.space,sci.astro,alt.sci.planetary In article <29APR199321594919@kelvin.jpl.nasa.gov>, baalke@kelvin.jpl.nasa.gov (Ron Baalke) writes: > 2. On April 23, a cruise science Memory Readout (MRO) was performed for the > Magnetometer (MAG) instrument. Analysis indicates the data was received > properly. Am I correct in assuming that the science instruments buffer their acquired data in onboard RAM, which is then downloaded upon receipt of the MRO command? Simon Brady You don't need a lot of fancy hardware for University of Otago Virtual Reality - just a walkman and an Dunedin, New Zealand attitude ------------------------------ Date: Thu, 29 Apr 1993 22:36:21 GMT From: "Ralph A.M.J. Wijers" Subject: Gamma Ray Bursters. WHere are they. Newsgroups: sci.astro,sci.space I feel compelled to complain: the statement that recent observations rule out merging neutron stars as sources of gamma-ray bursts is utterly false, even though it is popular enough to make it to BATSE press releases. The idea behind the statement is as follows: "if you smack two neutron stars together, or have a neutron star be gobbled up by a black hole, a lot of energy is released, enough for a gamma-ray burst at a cosmological distance. But, so the reasoning continues, this energy is released below a lot of matter, so the radiation becomes thermalized and you expect to see roughly a blackbody spectrum. The observed spectra are strongly non-thermal, so this model must be wrong." As so often, the fault lies with the imagination of the person who was trying to prove the model wrong rather than with the model. It may be that the initial energy release is not seen as a gamma-ray burst, but the 'fireball' of energy and matter that is created may spew out a relativistic flow. When this slams into the surrounding medium, a strong flux of non-thermal gamma rays results, which may carry off a substantial fraction of the initial total energy. All this is not my idea: it is in a series of papers by Martin Rees, Peter Meszaros (sorry for the missing accents:-) and co-workers. It is certainly not a complete model, but it may well be the best one around (summing over all proposed distance scales). An alternative proposal for what creates the initial fireball, by the way, is the so-called 'failed supernovae' scenario by Stan Woosley, in which a very massive star at the end of its life collapses to a black hole. If the stellar core was rotating, part of the infalling matter will be temporarily halted because it is supported by centrifugal force, and form a very dense neutron torus that accretes onto the black hole. This beast may spew out a jet along the rotation axis, which again constitutes relativistic flow. The rate of such events may be much higher than that of neutron star mergers, but the flux may be more strongly beamed, so that the net rate of bursts observed on Earth stays the same between the two scenarios, but the energy released per event can be a lot less in the failed supernova scenario. On another note: I do believe that the distance scale must ultimately be resolved via some classical astronomical method such as finding counterparts to the bursts at other wavelengths, or finding a definitive signature of some known class of objects in the distribution of positions and fluxes. Theorists have historically not been too successfull in finding the distance of any object by proving that there is only one possible way in which the object can work, and therefore it *must* be so-and-so. Ralph Wijers ------------------------------ Date: 29 Apr 1993 23:13:19 -0400 From: Pat Subject: Gamma Ray Bursters How energetic could they be? Newsgroups: sci.space,sci.astro In article <1rou8gINN7s4@gap.caltech.edu> palmer@cco.caltech.edu (David M. Palmer) writes: |prb@access.digex.com (Pat) writes: | |>In article <1993Apr26.200406.1@vax1.mankato.msus.edu> belgarath@vax1.mankato.msus.edu writes: |>|energetic for close by. for the coronal model, we found around 10^43 erg/sec. |>|And lastly, for the cosmological model an L=10^53. That's what you'd call |>|moderately energetic, I'd say. Any suggestions about what could put out that |>|much energy in one second? |>> -jeremy | |>big Capacitor :-) Real Big capacitor. | |It's been suggested. (Specifically, lightning strikes between clouds |in the interstellar medium.) | How big of a lightning rod, would you need for protection? and would you need jupiter as a ground plane. pat ------------------------------ Date: Fri, 30 Apr 1993 03:42:26 GMT From: Henry Spencer Subject: HST Servicing Mission Scheduled for 11 Days Newsgroups: sci.space,sci.space.shuttle,sci.astro In article <1993Apr29.201036.11256@den.mmc.com> zwork@starfighter.den.mmc.com (Michael Corvin) writes: >I expect that retrieving HST would involve 'damaging' it considerably in >order to return it to its cradle in the cargo bay. Most of the deployed >items (antennas and, especially, the solar arays) probably are not >retractable into their fully stowed position, even by hand... No, the thing is designed to be retrievable, in a pinch. Indeed, this dictated a rather odd design for the solar arrays, since they had to be retractable as well as extendable, and may thus have indirectly contributed to the array-flapping problems. The retrieval problems are exactly as stated: it would be costly, would involve extensive downtime (and the worry of someone finding a reason not to re-launch it), and would unnecessarily expose the telescope to a lot of mechanical stresses and possibilities for contamination. -- 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: 29 Apr 1993 22:43:40 -0400 From: Pat Subject: HST Servicing Mission Scheduled for 11 Days Newsgroups: sci.space,sci.space.shuttle,sci.astro In article <3t75nhg@rpi.edu> strider@clotho.acm.rpi.edu (Greg Moore) writes: | | As Herny pointed out, you have to develop the thruster. |Also, while much lighter, you still have to lift the mass of |the thruster to orbit, and then the thruster lifts its own |weight into a higher orbit. And you take up room in the payload >bay. > a yes, but the improvement in boost orbit to the HST is Significant, and that means you can then carry EDO packs and enough consumables so the SHuttle mission can go on long enough to also fix the array tilt motors, and god knows what else is going to wear out on the HST in the next 9 months. pat ------------------------------ Date: Fri, 30 Apr 1993 11:02:02 GMT From: Frederick Roeber Subject: Internet resources Newsgroups: sci.space In article , STK1203@VAX003.STOCKTON.EDU writes: > I am taking a course entitled "Exploring Science Using Internet". > For our final project, we are to find a compendium of Internet resources > dealing with a science-related topic. I chose Astronomy. Anyway, I was > wondering if anyone out there knew of any interesting resources on Internet > that provide information on Astronomy, space, NASA, or anything like that. Do you know of the world-wide-web? This is a global hypertext (well, hypermedia) network running on the internet. One of the nice things about it is that is understands and incorporates virtually all of the other systems being used, like WAIS, Gopher, FTP, Archie, etc. It is usually quite easy to add existing resources to the web. If you'd like to explore, I'd suggest getting the XMosaic program, written at the NCSA. It's an X-windows web browser, and is pretty slick. It can understand and cope with more than text: gif, jpeg, mpeg, audio, etc. There are other browsers, including a text-mode browser for people stuck on a text terminal, but I'm most familliar with mosaic. Under the page "The World-Wide Web Virtual Library: Subject Catalogue" (this is available under the Documents menu in mosaic, or by any browser via the URL http://info.cern.ch/hypertext/DataSources/bySubject/Overview.html ) there is a subject "Space Science." Currently this points to a page under construction, with only the NASA JPL FTP archive. I've volunteered to take over this page, and in fact I have a replacement with all sorts of information pointers (mostly gleaned from the sci.space FAQ). As soon as the overworked "Subject Catalogue" maintainer switches the "Space Science" pointer, it'll be visible. I'll post a short note when this happens. -- Frederick G. M. Roeber | CERN -- European Center for Nuclear Research e-mail: roeber@cern.ch or roeber@caltech.edu | work: +41 22 767 31 80 r-mail: CERN/PPE, 1211 Geneva 23, Switzerland | home: +33 50 20 82 99 -- "Sorry, baby, I can't take you to the pizza joint tonight, I've got to go back to the lab and split the atom." -- Ayn Rand, "What is Romanticism?" ------------------------------ Date: Thu, 29 Apr 1993 20:22:29 GMT From: Spiros Triantafyllopoulos Subject: Internet resources Newsgroups: sci.space In article STK1203@VAX003.STOCKTON.EDU writes: >I am taking a course entitled "Exploring Science Using Internet". >For our final project, we are to find a compendium of Internet resources >dealing with a science-related topic. I chose Astronomy. Anyway, I was >wondering if anyone out there knew of any interesting resources on Internet >that provide information on Astronomy, space, NASA, or anything like that. Robert McElwaine is the authoritative source of scientific data on Internet. He can be reached alt.fan.mc-elwaine... Spiros -- Spiros Triantafyllopoulos c23st@kocrsv01.delcoelect.com Software Technology, Delco Electronics (317) 451-0815 GM Hughes Electronics, Kokomo, IN 46904 "I post, therefore I ARMM" ------------------------------ Date: Fri, 30 Apr 1993 02:24:49 GMT From: JPL Public Information Subject: JPL Info Summary/"Our Solar System at a Glance" [Part 2] Newsgroups: sci.space westward at almost 1,200 kilometers (745 miles) per hour. Voyager 2 also noted a smaller dark spot and a fast-moving cloud dubbed the "Scooter," as well as high-altitude clouds over the main hydrogen and helium cloud deck. The highest wind speeds of any planet were observed, up to 2,400 kilometers (1,500 miles) per hour. Like the other giant planets, Neptune has a gaseous hydrogen and helium upper layer over a liquid interior. The planet's core contains a higher percentage of rock and metal than those of the other gas giants. Neptune's distinctive blue appearance, like Uranus' blue color, is due to atmospheric methane. Neptune's magnetic field is tilted relative to the planet's spin axis and is not centered at the core. This phenomenon is similar to Uranus' magnetic field and suggests that the fields of the two giants are being generated in an area above the cores, where the pressure is so great that liquid hydrogen assumes the electrical properties of a metal. Earth's magnetic field, on the other hand, is produced by its spinning metallic core and is only slightly tilted and offset relative to its center. Voyager 2 also shed light on the mystery of Neptune's rings. Observations from Earth indicated that there were arcs of material in orbit around the giant planet. It was not clear how Neptune could have arcs and how these could be kept from spreading out into even, unclumped rings. Voyager 2 detected these arcs, but they were, in fact, part of thin, complete rings. A number of small moons could explain the arcs, but such bodies were not spotted. Astronomers had identified the Neptunian moons Triton in 1846 and Nereid in 1949. Voyager 2 found six more. One of the new moons -- Proteus -- is actually larger than Nereid, but since Proteus orbits close to Neptune, it was lost in the planet's glare for observers on Earth. Triton circles Neptune in a retrograde orbit in under six days. Tidal forces on Triton are causing it to spiral slowly towards the planet. In 10 to 100 million years (a short time in astronomical terms), the moon will be so close that Neptunian gravity will tear it apart, forming a spectacular ring to accompany the planet's modest current rings. Triton's landscape is as strange and unexpected as those of Io and Miranda. The moon has more rock than its counterparts at Saturn and Uranus. Triton's mantle is probably composed of water-ice, but the moon's crust is a thin veneer of nitrogen and methane. The moon shows two dramatically different types of terrain: the so-called "cantaloupe" terrain and a receding ice cap. Dark streaks appear on the ice cap. These streaks are the fallout from geyser-like volcanic vents that shoot nitrogen gas and dark, fine-grained particles to heights of 2 to 8 kilometers (1 to 5 miles). Triton's thin atmosphere, only 1/70,000th as thick as Earth's, has winds that carry the dark particles and deposit them as streaks on the ice cap -- the coldest surface yet found in the solar system (-235 degrees Celsius, -391 degrees Fahrenheit). Triton might be more like Pluto than any other object spacecraft have so far visited. Pluto Pluto is the most distant of the planets, yet the eccentricity of its orbit periodically carries it inside Neptune's orbit, where it has been since 1979 and where it will remain until March 1999. Pluto's orbit is also highly inclined -- tilted 17 degrees to the orbital plane of the other planets. Discovered in 1930, Pluto appears to be little more than a celestial snowball. The planet's diameter is calculated to be approximately 2,300 kilometers (1,430 miles), only two-thirds the size of our Moon. Ground-based observations indicate that Pluto's surface is covered with methane ice and that there is a thin atmosphere that may freeze and fall to the surface as the planet moves away from the Sun. Observations also show that Pluto's spin axis is tipped by 122 degrees. The planet has one known satellite, Charon, discovered in 1978. Charon's surface composition is different from Pluto's: the moon appears to be covered with water-ice rather than methane ice. Its orbit is gravitationally locked with Pluto, so both bodies always keep the same hemisphere facing each other. Pluto's and Charon's rotational period and Charon's period of revolution are all 6.4 Earth days. Although no spacecraft have ever visited Pluto, NASA is currently exploring the possibility of such a mission. Comets The outermost members of the solar system occasionally pay a visit to the inner planets. As asteroids are the rocky and metallic remnants of the formation of the solar system, comets are the icy debris from that dim beginning and can survive only far from the Sun. Most comet nuclei reside in the Oort Cloud, a loose swarm of objects in a halo beyond the planets and reaching perhaps halfway to the nearest star. Comet nuclei orbit in this frozen abyss until they are gravitationally perturbed into new orbits that carry them close to the Sun. As a nucleus falls inside the orbits of the outer planets, the volatile elements of which it is made gradually warm; by the time the nucleus enters the region of the inner planets, these volatile elements are boiling. The nucleus itself is irregular and only a few miles across, and is made principally of water-ice with methane and ammonia -- materials very similar to those composing the moons of the giant planets. As these materials boil off of the nucleus, they form a coma or cloud-like "head" that can measure tens of thousands of kilometers across. The coma grows as the comet gets closer to the Sun. The stream of charged particles coming from the Sun pushes on this cloud, blowing it back like a flag in the wind and giving rise to the comet's "tails." Gases and ions are blown directly back from the nucleus, but dust particles are pushed more slowly. As the nucleus continues in its orbit, the dust particles are left behind in a curved arc. Both the gas and dust tails point away from the Sun; in effect, the comet chases its tails as it recedes from the Sun. The tails can reach 150 million kilometers (93 million miles) in length, but the total amount of material contained in this dramatic display would fit in an ordinary suitcase. Comets -- from the Latin cometa, meaning "long-haired" -- are essentially dramatic light shows. Some comets pass through the solar system only once, but others have their orbits gravitationally modified by a close encounter with one of the giant outer planets. These latter visitors can enter closed elliptical orbits and repeatedly return to the inner solar system. Halley's Comet is the most famous example of a relatively short period comet, returning on an average of once every 76 years and orbiting from beyond Neptune to within Venus' orbit. Confirmed sightings of the comet go back to 240 B.C. This regular visitor to our solar system is named for Sir Edmond Halley, because he plotted the comet's orbit and predicted its return, based on earlier sightings and Newtonian laws of motion. His name became part of astronomical lore when, in 1759, the comet returned on schedule. Unfortunately, Sir Edmond did not live to see it. A comet can be very prominent in the sky if it passes comparatively close to Earth. Unfortunately, on its most recent appearance, Halley's Comet passed no closer than 62.4 million kilometers (38.8 million miles) from our world. The comet was visible to the naked eye, especially for viewers in the southern hemisphere, but it was not spectacular. Comets have been so bright, on rare occasions, that they were visible during daytime. Historically, comet sightings have been interpreted as bad omens and have been artistically rendered as daggers in the sky. The Comet Rendezvous/Asteroid Flyby (CRAF) spacecraft will become the first traveler to fly close to a comet nucleus and remain in proximity to it as they both approach the Sun. CRAF will observe the nucleus as it becomes active in the growing sunlight and begins to have its lighter elements boil off and form a coma and tails. Several spacecraft have flown by comets at high speed; the first was NASA's International Cometary Explorer in 1985. An armada of five spacecraft (two Japanese, two Soviet and the Giotto spacecraft from the European Space Agency) flew by Halley's Comet in 1986. Conclusion Despite their efforts to peer across the vast distances of space through an obscuring atmosphere, scientists of the past had only one body they could study closely -- Earth. But since 1959, spaceflight through the solar system has lifted the veil on our neighbors in space. We have learned more about our solar system and its members than anyone had in the previous thousands of years. Our automated spacecraft have traveled to the Moon and to all the planets beyond our world except Pluto; they have observed moons as large as small planets, flown by comets and sampled the solar environment. Astronomy books now include detailed pictures of bodies that were only smudges in the largest telescopes for generations. We are lucky to be alive now to see these strange and beautiful places and objects. The knowledge gained from our journeys through the solar system has redefined traditional Earth sciences like geology and meteorology and spawned an entirely new discipline called comparative planetology. By studying the geology of planets, moons, asteroids and comets, and comparing differences and similarities, we are learning more about the origin and history of these bodies and the solar system as a whole. We are also gaining insight into Earth's complex weather systems. By seeing how weather is shaped on other worlds and by investigating the Sun's activity and its influence throughout the solar system, we can better understand climatic conditions and processes on Earth. We will continue to learn and benefit as our automated spacecraft explore our neighborhood in space. One current mission is mapping Venus; others are flying between worlds and will reach the Sun and Jupiter after complex trajectory adjustments. Future missions are planned for Mars, Saturn, a comet and the asteroid belt. We can also look forward to the time when humans will once again set foot on an alien world. Although astronauts have not been back to the Moon since December 1972, plans are being formulated for our return to the lunar landscape and for the human exploration of Mars and even the establishment of martian outposts. One day, taking a holiday may mean spending a week at a lunar base or a martian colony! - end - ------------------------------ Date: Fri, 30 Apr 1993 02:32:23 GMT From: Josh Hopkins Subject: Long term Human Missions Newsgroups: sci.space,sci.space.shuttle,sci.astro jgladu@bcm.tmc.edu (grungy) writes: >ward@pashosh.wisdom.weizmann.ac.il (Ward Paul) wrote: >> >1. Calculators >> >2. Teflon (So your eggs don't stick in the pan) >> >3. Pacemakers (Kept my grandfather alive from 1976 until 1988) >> >> I don't think touting contributions is a good idea. World War II produced >> many many beneficial spinoffs. Eg. Radar, jet aeroplanes, rocket technology. >> I don't think anyone would argue that World War II was, in and of itself, >> a good thing. >> >> If you want people to back the space program it must be a good thing in >> and of itself. >I disagree with what to tout, although I agree that the space program is >inherently a good thing. Most people today only care about "what will it >cost me?" and "what's in it for me?" and could care less about whether >something is simply worthwhile in and of itself. Our society has become >increasingly geared toward the short-term (which you could read as NOW!). >They couldn't care less about next week, much less next century. They want >something to show for the expenditure and they want it *now*. I think to some extent this is a case of stooping to their level. You assume that the general public "can't handle the truth" and then, based on this assumption, go for the fluff arguments. Then someone, who can understand a good argument, comes along and asks "why don't you just develop the spinoffs?" or "why can't we just get our spinoffs from some other program, like the military?" There are some good arguments for space development without relying on its side effects. I'm not ignoring the value of spinoffs. I simply think that the general public deserves more credit than you give them. >BTW: don't forget Velcro... And if you're going to use spinoffs you better make darn sure you are right. Teflon has been around since before NASA. As I understand it, Velcro was conceptualized by a french doctor who went walking in the woods and took the trouble to wonder how burrs stick to your clothes. Certainly velcro was available on hiking equipment by the early to mid sixties. I would need to see some good evidence before I believe that either of these would not be here today without NASA. -- Josh Hopkins jbh55289@uxa.cso.uiuc.edu "Find a way or make one." -attributed to Hannibal ------------------------------ Date: 30 Apr 93 08:23:41 GMT From: nsmca@acad3.alaska.edu Subject: Private Support of Exploration (Russian America) Newsgroups: sci.space Commericial support for exploration examples: Also much if Baranovs exploration and Utilization of Alaska (Russian America, also included parts of Washington state, Oregon, and N. California) was doen by private funds (yes some royal governmental funds at times..).. == Michael Adams, nsmca@acad3.alaska.edu -- I'm not high, just jacked ------------------------------ Date: Fri, 30 Apr 1993 08:43:11 GMT From: nsmca@acad3.alaska.edu Subject: Satellite around Pluto Mission? Newsgroups: sci.space Being wierd again, so be warned: Is there a plan to put a satellite around each planet in the solar system to keep watch? I help it better to ask questions before I spout an opinion. How about a mission (unmanned) to Pluto to stay in orbit and record things around and near and on Pluto.. I know it is a strange idea, but why not?? It could do some scanning of not only Pluto, but also of the solar system, objects near and aaroundpluto, as well as SETI and looking at the galaxy without having much of the solar system to worry about.. == Michael Adams, nsmca@acad3.alaska.edu -- I'm not high, just jacked ------------------------------ Date: 28 Apr 1993 21:21:21 -0400 From: Pat Subject: Space Manuevering Tug (was HST servicing mission_) Newsgroups: sci.space Given that what i described for the HST seemed to be the SMT, and given the mass amrgins on the discovery mission is tight enough that spacewalking has to be carefully constrained..... No EDO pallets, no spare Suits, no extra MMU's. WHy not do this? Quick Test Goldins philosophjy of faster cheaper, better. Build a real fast Space TUg, to handle the re-boost of the HST using clean Cryo fuels, and get it ready before the HST mission. If NASA could build Mercury in 13 months, they should be able to make an SMT in 9. How much would it need? Guidance package. Use a Voyager spare. Thruster gear, Use H2O2, or LOX/LH. Bus Use a Commsat. Grapple fixture. Use a stripped down Canadarm. Comms package. SPare X-band omni gear. pat ------------------------------ Date: Fri, 30 Apr 1993 07:41:19 GMT From: nsmca@ACAD3.ALASKA.EDU Subject: Space Manuevering Tug (was HST servicing mission_) Newsgroups: sci.space In article <1rnaih$jvj@access.digex.net>, prb@access.digex.net (Pat) writes: > > Given that what i described for the HST seemed to be the SMT, and given > the mass amrgins on the discovery mission is tight enough that spacewalking > has to be carefully constrained..... No EDO pallets, no spare Suits, > no extra MMU's. > > WHy not do this? > > Quick Test Goldins philosophjy of faster cheaper, better. > > Build a real fast Space TUg, to handle the re-boost of the HST using > clean Cryo fuels, and get it ready before the HST mission. > > If NASA could build Mercury in 13 months, they should be able to make > an SMT in 9. > > How much would it need? > > Guidance package. Use a Voyager spare. > > Thruster gear, Use H2O2, or LOX/LH. > > Bus Use a Commsat. > > Grapple fixture. Use a stripped down Canadarm. > > Comms package. SPare X-band omni gear. > > pat And then why not build a space dock.. Either inflated or not.. some place a crew can work on a item without having to wear much of the items they have to for spae.. such as most of he bulky suit.. More idea to come.. == Michael Adams, nsmca@acad3.alaska.edu -- I'm not high, just jacked ------------------------------ Date: 30 Apr 93 11:55:29 GMT From: devdjn@space.alcbel.be Subject: Statement by NASA Administrator Daniel S. G Newsgroups: sci.space If this man Clark is a NASA administrator then god save NASA. Of course the Shuttles record is unrivaled ! There is only one Shuttle. Furthermore, there is only likely to be one Shuttle now that Hermes and Boron are effectively cancelled. These officials should spend more of their time explaining to their European and Asian partners how we are expected to believe in them when their paymasters change their minds on major international projects everytime a new US administration takes office (considering the major impacts this has on the European and Asian (Japanese) industry). It is also appreciated how this affects American industry. I am of course talking about Space Stattion Freedom. --- Dennis Newport, email: devdjn@space.alcbel.be Alcatel Bell Telephone, Berkenrodelei 33, phone: (+32) 3/829.5488 2660 Hoboken, Belgium. ------------------------------ Date: Fri, 30 Apr 1993 07:01:55 GMT From: James Thomas Green Subject: Teflon Development. Newsgroups: sci.space,sci.space.shuttle,sci.astro,sci.materials hausner@qucis.queensu.ca (Alejo Hausner) Pontificated: > >Sorry to split hairs, but I just read in "The making of the atomic >bomb"(*) that teflon was developed during world war 2. A sealant was >needed for the tubing in which uranium hexafluoride passed as it was >gradually enriched by difussion. UF6 is very corrosive, and some very >inert yet flexible material was needed for the seals. > To split a split hair, I believe that teflon (-CF4- monomer) was "discovered" by accident when someone I don't remember found what he thought was a liquid (or gas?) had turned to a solid... It just happend to fit the bill for the above use... I'm crossposting to sci.materials so perhaps someone in the know might elaborate... /~~~(-: James T. Green :-)~~~~(-: jgreen@oboe.calpoly.edu :-)~~~\ | "I know you believe you understand what it is that you | | think I said. But I am not sure that you realize that | | what I said is not what I meant." | ------------------------------ End of Space Digest Volume 16 : Issue 508 ------------------------------