Space Digest Fri, 13 Aug 93 Volume 17 : Issue 020 Today's Topics: Dean Drive [Was Re: Starlite, Super Material? engine failures and safety (3 msgs) funny space Mars Observer's First Photo Moon Rocks For Sale Name suggestion for MO. S.H. is a hypocrite The old yellow and magenta 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: 13 Aug 1993 07:38:06 GMT From: George William Herbert Subject: Dean Drive [Was Re: Starlite, Super Material? Newsgroups: sci.space In article , Henry Spencer wrote: >It is *almost* >certain that what he had was a gadget that could fool a scale but did not >produce actual thrust, but the Dean Drive was never put to the definitive >pendulum test [...] There have been recent efforts, if I recall, by serious and skeptical physicist-type science fiction authors who wanted to get their hands on the Dean hardware (not patent, hardware) and check this out. I don't think they got anywhere. It's a worthwhile thing to do; it'll either nail the coffin closed on a wierd idea and let us all consign the Dean Drive to the FAQ safety, or it will be one of the most wonderful and confusing discoveries of the century. But I think that locating Dean's hardware proved elusive. I wish them luck... -george william herbert Retro Aerospace ------------------------------ Date: Fri, 13 Aug 1993 03:37:48 GMT From: Henry Spencer Subject: engine failures and safety Newsgroups: sci.space In article h.hillbrath@genie.geis.com writes: >However, it is not at all clear that having a restart capability helps, it >seems that it could make things a lot worse. Another chance for the >engine to make like a bomb, after having already "dodged the bullet"... >...The only thing remotely similar is that on the >Centaur, there was an automatic sequence, even before the first of >the recent start failures, to try starting twice. The Centaur people may have been influenced by having an engine that appears to be exceptionally reluctant to fail catastrophically. I've been told that since a couple of incidents in early development -- which were traced to a test-stand interaction -- there have been zero cases of catastrophic failure of an RL10. (Does your database back this up?) -- "Every time I inspect the mechanism | Henry Spencer @ U of Toronto Zoology closely, more pieces fall off." | henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 13 Aug 93 04:09:58 GMT From: hvanderbilt on BIX Subject: engine failures and safety Newsgroups: sci.space For what it's worth, the airliner that lost all three engines due to a maintenance problem then barely limped back to land on one engine was an L-1011, flying out of Florida (Miami?) and headed out over the Atlantic. A mechanic had reinstalled oil sump drain plugs on all three engines without bothering with O-ring seals. This case was a factor in what I believe is a requirement that airlines doing two-engine overwater flights have separate mechanics working on each engine, lest a single mechanic pull the same bonehead mistake on both engines. ------------------------------ Date: 13 Aug 1993 04:05:42 -0400 From: Matthew DeLuca Subject: engine failures and safety Newsgroups: sci.space In article <24ap3p$60o@access.digex.net> prb@access.digex.net (Pat) writes: >Pre shuttle, all US manned spacecraft seemed to do a nice >un powered water ditch, with only the notable loss of one capsule. Argh, talk about misuse of the language. U.S. capsules did not ditch, they were designed to splash down in the ocean. Almost by definition, ditching is an unplanned act. >wings don't seem that vital for spacecraft. No, but they are certainly desirable. They make landing a lot easier and a true winged spacecraft (NASP) has wonderful engine-out abort modes. Loss of power on ascent for normal rockets is almost certainly a fatality, as is loss of power on descent for something like DC-X. -- Matthew DeLuca Georgia Institute of Technology "Never fight a land war in Asia." Office of Information Technology matthew@prism.gatech.edu - MacArthur ------------------------------ Date: 12 Aug 1993 23:11:21 -0400 From: Pat Subject: funny space Newsgroups: sci.space I would have asked the key question, why your lab did not have a ramp already? every computer lab i ever worked in has always had a ramped entrance door, double wide, to get the big gear in and out anyway. Now these ramps may not be OSHA/CABO compliant, but a case of beer left un-attended during inspection would probably solve the problem. -- I don't care if it's true. If it sounds good, I will publish it. Frank Bates Publisher Frank Magazine. ------------------------------ Date: Fri, 13 Aug 1993 04:13:57 GMT From: Frank Crary Subject: Mars Observer's First Photo Newsgroups: sci.space,sci.astro,alt.sci.planetary In article <24evbd$e9a@access.digex.net> prb@access.digex.net (Pat) writes: > the project scientists have one advantage over everyone else. >they get to choose teh onbjects imaged. I am sure somehow that if ones >PhD was in crustal dynamics, one would have very different >targets for observation then someone interested in surface chemistry. That's true only of imaging science, and not even all of that. The instruments I'm (remotely) connected with on Galileo are a good counter example: The extreme ultraviolet and plasma instruments. The plasma instrument just passively measures the plasma density distribution as a function of energy per charge in seven directions and the mass per charge in three, at the spacecraft's cruuent location. The spacecraft's trajectory isn't in the hands of the PLS investigators, although scientific needs were considered (we still miss the Io flux tube and have to live with the less decisive perturbations and wake...) Even the directional sensivity is tied to the spacecraft's orientation and out of the investigator's hands: Spacecraft opperational requirements dictate that. The extreme UV imaging is a simple slit imager (i.e. it has no resolution at all in one direction, it just gives the intensity summed over the "verticle" for a given "horizontal" position.) There isn't too much creative control over sweeping a slit back and forth... The magnetometer, plasma wave instrument, dust detector, energetic particle detector and for that matter, the entire entry probe are in the same situation: The investigator's reward is a first crack at the data, not control over what is observed. >I also doubt anyone not intimately associated with the program will be able >to make much progress with the raw data. I'm afraid you are mistaken. At a guess (judging from the names on relevant papers and the typical number of investigators per instrument) the people "intimately associated" don't even add up to a tenth of the people who could use the data to great advantage. For example, Jack Coronnary (sp?) at GSFC is the Jovian magnetic field modeling deity, but if I knew I'd get the Galileo magentometer data at the same time he did, even a lowly grad student like me might be able to publish a good, revised field model first. It's a field starved for data and getting it first is very important. >...I am sorry, these are >taxpayer funded projects, US Citizens should get equal access >to the raw data and the volume sets. That's an interesting assertion: The B-2 bomber is also a taxpayer funded project. As a taxpayer, should I get equal access to it's blueprints? The taxpayers wouldn't benefit much at all from that program if it's details were public and available to everyone. Similarly, getting good, meaningfull science out of a spacecraft requires getting the best investigators into the program. That means offering them a carrot such as first access to the data. Frank Crary CU Boulder ------------------------------ Date: Thu, 12 Aug 1993 23:42:31 -0400 From: Allan Bourdius Subject: Moon Rocks For Sale Newsgroups: sci.space,sci.astro >The Soviets had three successful unmanned lunar sampler missions that brought >back lunar material from the Moon: Luna 16 (1970), Luna 20 (1972) and >Luna 24 (1976). With Luna 15, they attempted to return the first lunar samples >ever just days before Apollo 11, but the Soviet spacecraft crashed on the Moon. >The Soviets have also land and operated two rovers on the Moon, which something >the US has never accomplished. What of the Lunar Rover Vehicles carried to the moon on Apollos 15, 16, and 17? Sounds like that's 3 to 2 in favor of the USA. They carried humans, by the way... Allan ------------------------------------- Allan Bourdius [Applied History/Industrial Management] PA Rho Chapter of Phi Kappa Theta #017-1051 1069 Morewood Avenue, Pittsburgh, PA 15213 (412) 268-5504 or ab3o+@andrew.cmu.edu "More geese than swans now live, more fools than wise." ------------------------------ Date: 12 Aug 1993 22:50:54 -0400 From: Pat Subject: Name suggestion for MO. Newsgroups: sci.space Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU How about the Mutch Observatory? pat -- I don't care if it's true. If it sounds good, I will publish it. Frank Bates Publisher Frank Magazine. ------------------------------ Date: Thu, 12 Aug 93 22:29:03 PST From: jhardin@splat.com (John Hardin at home) Subject: S.H. is a hypocrite fred j mccall 575-3539 sez: } (rant rant rant, concluding with:) } } You couldn't buy a clue if someone wrote the check for you and pinned } it to your shirt before they led you to the counter. } Fred: Your row with S.H. (H.S.? Suzie?) is becoming more annoying than the original postings. Just kill-file 'em and be done with it. FWIW, I tend to agree with you. S.H., if indeed a neophyte, would do everyone a favor by lurking for six months or so to pick up on netiquette and methodology (and who's who) before posting anything. However, I'm not convinced sci.space is a good place for such a learning experience. My word, the bad habits that would be picked up... :-) #lurk on -- ---------------------------------------------------------------- John Hardin jhardin@splat.com 76076.22@compuserve.com ------------------------------ Date: Fri, 13 Aug 93 05:05:54 GMT From: Bob Greschke Subject: The old yellow and magenta Newsgroups: sci.space Hi all! This may have been asked before but how much radiation exposure do astronauts receive during your typical mission? Are they subject to the same limits that radiation workers are (like do they have to hang up their pressure suits when they hit their legal limit)? Do they wear any dosimetry? Any special clothing (I can't imagine that space underware provides much of a 1/10 thickness)? I just used to be a submarine nuke and have always been curious about this. I've never heard much on the subject...should I be asking these questions?? (I'm not going to be audited, am I??) -- Bob Greschke | National Radio Astronomy Observatory / Internet: bgreschk@nrao.edu | VLBA Operations, POB O, Socorro, NM 87801 C(|--( ----------------------------+------------------------------------------ /| \ 12m, 140ft, GBT, VLA, VLBA...NRAO: For All Your Radio Astronomy Needs -@-@-@- ------------------------------ End of Space Digest Volume 17 : Issue 020 ------------------------------