Date: Sun, 9 Aug 92 05:01:59 From: Space Digest maintainer Reply-To: Space-request@isu.isunet.edu Subject: Space Digest V15 #089 To: Space Digest Readers Precedence: bulk Space Digest Sun, 9 Aug 92 Volume 15 : Issue 089 Today's Topics: Comments, Misc Energiya's role in Space Station assem (3 msgs) Energiya's role in Space Station assembly Hubble used for spying? + other neat info More second-hand info on TSS Primary Cosmonaut Training Russian Comment on Soyuz vs Shuttle Seeding Mars with life SPS fouling astronomy 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: 9 Aug 92 05:53:36 GMT From: George Hastings Subject: Comments, Misc Newsgroups: sci.space There is NO WAY you could fit four in a SOYUZ-TM. I've run RENDEZVOUS/DOCKING SIMS in them, and three in flight suits is TIGHT! With ascent/descent pressure suits on, you have to wear a device sort of like a "knee-bra" to draw your knees up close to your chest to fit. The three crew are placed in a slightly radial seat pattern, with feet closer to each other than shoulders, and the control panels are practically in your face. There is no stroke area beneath the seats, as in the Apollo capsule. A fourth person in the SOYUZ-TM would make it impossible to use the controls, and would seriously injure or crush everybody aboard on landing, if it were possible to get that far! -- ------------------------------ Date: 9 Aug 92 01:24:19 GMT From: Gerald Cecil Subject: Energiya's role in Space Station assem Newsgroups: sci.space In article 3096@iti.org, aws@iti.org (Allen W. Sherzer) writes: >In article <5446@ucsbcsl.ucsb.edu> 3001crad@ucsbuxa.ucsb.edu (Charles Frank Radley) writes: >>SSF is in 28.5 deg orbit because congress limited the number of >>Shuttle flights, and NASA wants to squeeze as much mass as it can >>into each Shuttle. > >But if you use Energia, mass isn't a problem anymore. The internal NASA >report on using Energia has it up with four Energia and Shuttle flights; >that leaves plenty for whatever you want. Any chance of getting a summary of that internal report on the Net? In article 1544@idacrd.UUCP, purtill@idacrd.UUCP (Mark Purtill) writes: >gary@ke4zv.uucp (Gary Coffman) writes: >>Another point is that Energia has only flown a handful of times (two? >three?), and as I recall one of those flights was not exactly a >success (the payload ended up in the Pacific Ocean, although >apparently this was not directly related to Energia, but rather to the >secondary booster or something like that. The full Energiya stack has flown twice. On the first flight the core (2nd) stage was not fully fueled. The 3rd (kick) stage failed, and the unspecified payload burned up. The ascent profile indicated that performance of the first 2 stages was nominal. The first stage (liquid stap-ons) boosters have been used independently several times for satellite launches (another advantage of Energiya components over the Shuttle), before and after the 1st Energiya launch. They appear to be as reliable as other liquid boosters. CIS engineers were apparently satisfied enough with Energiya's 1st flight performance that they orbited the Buran Space Shuttle on the 2nd flight, a unique piece of hardware. The 3rd flight was to have been another shuttle flight this year, but has been delayed indefinitely because the CIS Shuttle program has no funds. In an earlier posting I misquoted the payload of a fully fueled Energiya: it is 153 metric tons to LEO (not 103) with 4 strap-ons and 238 metric tons with 6. (GEO figures are increased accordingly.) Compare this with the 30 or so of the Shuttle. Only the 4 strap-on variant has flown. I've calculated some simple dog-leg trajectories for Energiya to get down to 28.5 degs. Useful mass can be delivered only if the cryogenic (2nd) core stage can be restarted (I don't know if this is possible), and even then there are MAJOR payload losses because you have to travel 3300 km down toward the equator before the trajectory can deflect into the SSF plane. This requires several km/s tangential velocity at a large apogee. A 45 deg inclination for SSF requires 940 km down range, much better. The core is fired at launch in conjunction with the strap-ons. The strap-ons burn out at ~40 km altitude (& can supposedly be reused), so they have no role in the dog-leg. You need to run the core stage for roughly 90 seconds after staging to get enough delta_V to ballistically coast to the correct latitude. The core normally runs for about 400 seconds, including ~160 seconds concurrently with the strap-ons. There are conflicting reports on the reusability of the core, however only a couple of Energiya launches are needed to orbit SSF at a 45 deg inclination. >>In article <1992Aug4.140921.19282@aio.jsc.nasa.gov> pettengi@ial1.jsc.nasa.gov (James B. Pettengill) writes: >>International relations have a way of changing rapidly. I agree, let's dump ESA now. I also worry that California will secede, taking most of our space capability with it. >>Even if the CIS remains friendly, they can't yet be considered a >>reliable business partner. Dealing with them now would be like letting >>Frank Lorenzo run your airline. The odds of bankruptcy are too high. I'd say that the odds of ending up with a Space Station would be IMPROVED by launching it on a heavy lift vehicle; Energiya is the ONLY EXISTING HLV. Presumably NASA has realized that the Shuttle CANNOT POSSIBLY deliver all the Station components without loss of a vehicle. There have certainly been enough independent studies of that. The best way to cement relations is to COOPERATE on mutually beneficial projects. Energiya use in Space Station assembly would certainly NOT be commercial, because there is nothing that makes ANY commercial sense about the Space Station, and certainly nothing worth worrying about re technology transfer. The CIS nations have favored nation trade status and can buy anything they want (or can afford). --- Gerald Cecil 919-962-7169 Dept. Physics & Astronomy U of North Carolina, Chapel Hill, NC 27599-3255 USA -- Intelligence is believing only half of what you read; brilliance is knowing which half. ** Be terse: each line on the Net costs $10 ** ------------------------------ Date: 9 Aug 92 02:47:00 GMT From: seds%cspara.decnet@Fedex.Msfc.Nasa.Gov Subject: Energiya's role in Space Station assem Newsgroups: sci.space In article <1992Aug8.210850.3096@iti.org>, aws@iti.org (Allen W. Sherzer) writes... >In article <5446@ucsbcsl.ucsb.edu> 3001crad@ucsbuxa.ucsb.edu (Charles Frank Radley) writes: > >>SSF is in 28.5 deg orbit because congress limited the number of >>Shuttle flights, and NASA wants to squeeze as much mass as it can >>into each Shuttle. > >But if you use Energia, mass isn't a problem anymore. The internal NASA >report on using Energia has it up with four Energia and Shuttle flights; >that leaves plenty for whatever you want. > >In addition, since you needn't worry nearly so much about mass, the cost and >risk of the entire program goes down quite a bit. > Considering the operational record of Energia and its Cyclone Boosters I would have grave misgivings about putting a fourth of the space station on Energia. Much better would it be to put it on the Saturn which was a zero failure system. Also has anyone even looked at the dynamics of the vibration environment? Bet you would have to do a lot of beefing up to get station elements on Energia from a structural standpoint. So there is a trade off in program risk here Allan not a reduction. That risk at this time would seem to be rather large. Also Allen the numbers that I quoted the other day on structural qualification levels (payloads)on the Shuttle (+/- 10 G in Z, +/- 6 G in X and Y) are to qualify at a 1.1 factor for a very benign shuttle system. Remember that the max thrust generated only gives you three g but the qualification levels here are there to deal with the low frequency vibrations that are greater than the RMS g values. For other launchers without throttable engines or with large thrust chambers, the qualification g factors are much higher. This is also true of cargos on the return with any technology other than the shuttle's aeroassisted reentry. Dennis, University of Alabama in Huntsville ------------------------------ Date: Sun, 9 Aug 1992 04:05:41 GMT From: Henry Spencer Subject: Energiya's role in Space Station assem Newsgroups: sci.space In article <8AUG199221471635@judy.uh.edu> seds%cspara.decnet@Fedex.Msfc.Nasa.Gov writes: >Considering the operational record of Energia and its Cyclone Boosters I would >have grave misgivings about putting a fourth of the space station on Energia. Energia (two stages) and its strap-ons (one stage) have a flawless record as far as I know. The one Energia failure was a payload engine failure. Unless I've missed one, all the Tsyklon failures have been upper stages. >Much better would it be to put it on the Saturn which was a zero failure >system... High though my opinion of the Saturn V is, anyone who calls the first Energia launch a failure would have to work real hard to call the second Saturn V launch a success. -- There is nothing wrong with making | Henry Spencer @ U of Toronto Zoology mistakes, but... make *new* ones. -D.Sim| henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 9 Aug 92 02:25:57 GMT From: Gerald Cecil Subject: Energiya's role in Space Station assembly Newsgroups: sci.space Ooops, mistyped. You have to run the Energiya 2nd stage for 210 secs after 1st stage burnout to get to 435 km apogee (SSF's orbit) and ~900 km range for the dog-leg. This elliptical transfer orbit has an apogee tangential velocity of 3.3 km/s. The full burn duration of the Energiya core is 470 sec, with ~15 sec on the pad and 156 sec concurrent with the strap-ons. 6 strap-on LEO mass is 230 metric tons. -- Gerald Cecil 919-962-7169 Dept. Physics & Astronomy U of North Carolina, Chapel Hill, NC 27599-3255 USA -- Intelligence is believing only half of what you read; brilliance is knowing which half. ** Be terse: each line cost the Net $10 ** ------------------------------ Date: 9 Aug 92 03:45:00 GMT From: Chuck Forsberg WA7KGX Subject: Hubble used for spying? + other neat info Newsgroups: sci.space,sci.astro In article <18201.2a7feff4@levels.unisa.edu.au> steven@sal.levels.unisa.edu.au writes: >was also a mention of the backup mirror made by Kodak (which was not flawed). >It is currently sealed inside a big box and no-one is allowed to look inside How many more things have to go wrong with Hubble before it becomes preferable to make a second unit around the good mirror, and replace the current satellite as a unit? -- Chuck Forsberg WA7KGX ...!tektronix!reed!omen!caf Author of YMODEM, ZMODEM, Professional-YAM, ZCOMM, and DSZ Omen Technology Inc "The High Reliability Software" 17505-V NW Sauvie IS RD Portland OR 97231 503-621-3406 ------------------------------ Date: Sun, 9 Aug 1992 04:01:20 GMT From: Henry Spencer Subject: More second-hand info on TSS Newsgroups: sci.space In article mcdonald@aries.scs.uiuc.edu (J. D. McDonald) writes: >>The reason the solutions are over-engineered, at colossal cost, is all >>the people who cry "incompetents!" when something being tried for the >>very first time doesn't work. The natural response is to put more money >>and effort into trying to avoid failures. This cripples projects even >>when ample funding is available. Worse, it doesn't really help much. > >But how hard would it be to carry several spooling systems, and try >them all? Not hard at all... except that Congress will then ask why you want to spend its hard-stolen money on developing more than one. After all, if you know how to build one that will work, you only need one, and if you don't know how, you shouldn't be wasting money trying. The idea that things have to be debugged is not one they really understand. (For that matter, NASA management doesn't grasp it very well either.) Besides, unless you have several different concepts (not just several different implementations) and aren't sure which will work best, it *is* wasteful to develop more than one. You do that only if you're in a big hurry and can't afford to spend time debugging. The right thing to do is to fly the thing multiple times and/or equip and train the crew as development engineers (not just switch-flipping technicians). -- There is nothing wrong with making | Henry Spencer @ U of Toronto Zoology mistakes, but... make *new* ones. -D.Sim| henry@zoo.toronto.edu utzoo!henry ------------------------------ Date: 9 Aug 92 06:29:34 GMT From: George Hastings Subject: Primary Cosmonaut Training Newsgroups: sci.space American Primary Cosmonaut Training I pulled on the T-shaped handle with the fingers of my right hand, a quick tug and release. I heard the short high-pitched hoot of control gas escaping from the four corners of the Ikarus "flying chair", and grinned as the Russian manned maneuvering unit began to back me away from the airlock of MIR. A light touch sideways on the other hand controller activated the yaw thrusters, and the view of MIR slewed to the right as the Ikarus began to rotate me toward the left. The main core of the space station drifted past my face plate, and the Kvant module came into view. When I had turned far enough to see the Kristal module directly in front of me, I flicked a toggle switch under my fingers, and the automatic stabilizers kicked in. They canceled out any movements I had initiated, holding me in place about a hundred meters from the MIR, pointing in the direction I wanted to move next. In automatic mode, I pushed forward on the controller, and the space station loomed larger in my field of view as I approached. Releasing the pressure on the hand controller, I came to a halt, floating in the blackness within easy reach of the hand holds on the space station exterior. I could hear the voice of the commander speaking in Russian, and the translator's voice in my earphones relayed his congratulations on the successful completion of my first flight in the cosmonaut mobility unit. Suddenly the unit lurched back sharply, the space station began to recede, and a bright white light split the darkness at the edges of my vision as the chair was pulled out of the black box surrounding the simulator. It was time for the next trainee to have an opportunity for a familiarization run on the computer driven equipment. If I had been preparing for an actual EVA assignment on a MIR flight, I would have spend hundreds and hundreds of hours with this sophisticated simulator, but I had only a week to sample of all the major areas of training experienced by guest cosmonauts preparing to travel to the Russian MIR Space Station There were an even dozen of us here as guests, the first American civilians ever to be admitted to primary spaceflight training at the Yuri A. Gagarin Cosmonaut Training Center in Zhvuzhdny Gorodok (Star City). Two were professional cameramen, here video taping for a television documentary. Four were people with a keen interest in the Russian space program. The other six were all teachers, applicants in a competition to select an American guest cosmonaut flight to the MIR Space Station as Educator In Space. Aerospace Ambassadors, a private American organization, has a signed contract with Russian space officials to act as the coordinating agency for the solicitation of science experiments to be transported on a paying basis to MIR. When enough experiments have been booked to pay for the flight, one American educator will ride as a guest cosmonaut on a Soyuz flight to the MIR Space Station. Our week in Star City was an intense, compressed introduction to the nine to twelve months of training the selected Educator In Space will experience. We attended lectures and briefings by top Russian scientists, engineers, and cosmonauts. Inside the full size training model of the huge MIR space station, became familiar with the general configuration of the orbital complex and its life support systems. We were given flight physicals. We experienced the physiological effects of high altitude in the hypobaric chamber, where the air pressure was reduced to reach the equivalent of 5,000 meters. We rode the centrifuge, where we experienced the forces felt during liftoff in the Soyuz-TM spacecraft. The normal forces felt during a Soyuz-TM flight are only about 3 G's, the same experienced during a space shuttle flight. The maximum centrifuge load of up to six G's would only be endured in the event of an emergency ballistic reentry. Rendezvous and docking training inside the Soyuz-TM simulator is not for the claustrophobic. The spacecraft is designed for maximum efficiency, and that means minimum weight and volume. The three cosmonauts in a Soyuz-TM lie on their backs in acceleration couches just big enough to cradle body, head, and upper arms. The footrests placed close together create a radial arrangement for the seats. With my feet in place, my knees were bent almost up to my chest. We all gained a new respect for extravehicular operations when we donned the "Orland" EVA space suits used outside MIR. When you hear that the suit is entered through a door in the back of the integrated life support system, it sounds easy. It isn't! Blood pressure, respiration, and heart rate monitoring telemetry were attached to my body. The hooded cooling garment that I put on next had woven into it tubes about the diameter of my little finger. Chilled liquid circulated through the tubes removes excess body heat from head, arms, torso, and upper legs. Cloth mesh headgear equipped with earphones and microphones, worn under the liquid cooling garment hood allowed me to communicate from inside the space suit. Sitting on the edge of the space suit door, it is easy to slip your feet into the legs. Left arm into the sleeve. I ducked my head and hunched my right shoulder at the same time to squeeze through the narrow opening. As I struggledd to get both hands into the attached gloves, I thrust my face close to the front of the helmet. Breathing hard , I could feel the carbon dioxide level building up. Groping down blindly across my body with my left hand, I found the handle on the end of a cable. Tugging on it hard, I strained to lift it over the edge of a hook on the front of the suit, and I could feel the door in the back of the suit being pulled closed. I grabbed a lever at the side of the suit, and shoved it down, sealing the door. I heaved a sigh of relief as fresh air began to blow into the helmet and the liquid cooling garment began to work. As the suit came up to full working pressure, I found it easy to move the rotating shoulder and wrist joints on the suit, but bending elbows and fingers was hard work. Cosmonauts must be in excellent physical condition to work in EVA suits outside the MIR! The highlight of the was weightlessness training on board the Ilushin-76 MDK aircraft. Ten of us sat expectantly on the four inch padding covering the floor of the square twenty meter long fuselage of the plane while it climbed to high altitude. As the pilot nosed the plane into a slight dive to pick up speed, I felt as though I was in a fast dropping elevator. The plane pulled up sharply, engines at full power, and I sank into the cushioned floor covering as the G forces built up. At maximum speed and rate of climb, the pilot eased back on the throttle and pushed forward gently on the controls. As the aircraft nosed over, the floor floated out from under me, and I was floating weightless, feet and body off the floor, hanging on to the handrail on the wall. There was no sense of falling, just freedom and elation. As I looked around I saw one cameraman floating in the middle of the room, feet flailing around, but eye pressed firmly to the view finder, determined to catch on tape this extraordinary event. His partner, hanging on to a railing, pulled him to the floor just as we pulled out of the dive twenty five seconds later, and assisted him with the large video camera that now weighed three times as much as it should. As the IL-76 MDK flew through each parabolic arc I was weightless for about thirty seconds. Each time, I was given a different skill to practice by the cosmonaut working with me. I practiced moving hand over hand along railings on the wall. I pushed off the floor gently, and floated to the ceiling, staying there until pushing myself back to the floor. I pushed off the wall with the lightest muscle movement, and flew across the room. I stuck my feet under floor straps and moved around a 100 kilogram package that was weightless, but still had a 100 kilos of mass. By the time we had completed ten flight arcs, I had been weightless for about five minutes. The five trainees that were busy by this time filling plastic bags with this morning's breakfast were glad that this part of the training was over, but the remaining five were ready to fly another ten arcs. We're hoping to be included in the full length guest cosmonaut training program in the not too distant future, so that one of us can feel the freedom of movement in weightlessness and the reward of space science experimentation aboard the MIR space station. BIO: George Hastings was an aerospace education specialist for NASA's Educational Programs Office for more than ten years. He currently helps run spaceflight simulations in the Signet Challenger Center in Richmond, Virginia and teaches astronomy and space science classes for the Richmond Mathematics and Science Center. George Hastings GHASTINGS@vdoe386.vak12ed.edu Mathematics & Science Center CompuServe 72407,22 2401 Hartman Street Richmond, VA 23223 -- ------------------------------ Date: 9 Aug 92 02:58:00 GMT From: seds%cspara.decnet@Fedex.Msfc.Nasa.Gov Subject: Russian Comment on Soyuz vs Shuttle Newsgroups: sci.space In article <1992Aug8.211604.3508@iti.org>, aws@iti.org (Allen W. Sherzer) writes... >In article Wales.Larrison@ofa123.fidonet.org writes: > >> According to the trade press, cosmonaut Anatoly Artsebarsky >>stated at a press conference in Chicago last Tuesday, regarding the >>Buran: > >> "We need it (Buran) to bring back (to Earth) materials and >>experiments from the station... When using the Soyuz spaceship, we >>have to abandon some experiments and materials due to its limited >>(return) capability." > >But at what cost? The Shuttle is killing the entire program. We can't >design a replacement because Shuttle operations costs are so high that >is uses all the money which might go to a replacement. We won't go >anywhere so long as we have this millstone around our necks. > >I think what he ment was that they needed the ability to return larger >payloads. That doesn't mean it MUST be Buran. > > Allen > No Allen it is a shortsighted Legislative branch whose only aim is more bread and circuses in order to get reelected that is the problem. We would be on Mars today just from the legal fees from the disaster of the Environmental Superfund legal battles. Only when the space advocacy community comes up with a coherent, workable plan to bring wealth from the solar system to the earth will we get a real space program. To date we have been busy happily cutting each others throats to pursue our pet theologies of manned vs unmanned exploration. The space program needs both. It MUST bring benifit to the people of the earth in a meaningful way beyond the ephemeral justification of knowledge. A man out of work and living on the street does not give a hoot in hell for all of your knowledge put together unless it will help him or her get a job. The space advocacy community as a whole is responsible for the lack of a reasoned, beneficial policy of space exploration. We will continue in this mire until we come together, quit whining about this or that program, and put forward a program that is equivalent in scope and benefits to the westward expansion of America in the last century. My apologies to the international readers of this but this analogy holds true. Dennis, University of Alabama in Huntsville Followups to Talk.Politics.Space ------------------------------ Date: 9 Aug 92 07:02:05 GMT From: Nick Janow Subject: Seeding Mars with life Newsgroups: sci.space tolman%asylum.cs.utah.edu@cs.utah.edu (Kenneth Tolman) writes: > What do you think [of seeding Mars with Terran microorganisms]? I have no problem with it, but I hope it would not be done until we have thoroughly searched Mars for Martian life, and have studied the existing unique features of Mars (superoxidized soil, how that soil interacts with dew, how the hydrological cycle works without life, etc). We can learn a great deal about how our hydrological cycle functions (and how microorganisms affect it) by studying a similar planet without microorganisms. So yes, seeding mars with Terran life might be a good idea someday, it is a bad idea today. It would be such a waste of unique and valuable information. -- Nick_Janow@mindlink.bc.ca ------------------------------ Date: 9 Aug 92 03:44:50 GMT From: "Frederick A. Ringwald" Subject: SPS fouling astronomy Newsgroups: sci.space In article <1992Aug07.172531.129551@cs.cmu.edu> 18084TM@msu.edu (Tom) writes: > >(My biggest problem with SPS still is: do you really think you can make > >a living at it? Seems to me that ground-based Solar would be amazingly > >cheaper and less trouble. Wind is making surprisingly good progress, > >too. And these contraptions are made of native materials, too: from > >Earth.) > > About the resource-value. Earth can't provide as much solar energy as is > available in space, as you know. And even if you could get decent > solar power despite clouds, etc., you still have competing uses of the > land invloved. [...] > From muscles, to wood, to coal, to > oil, we've seen living standards increase with energy use. SPS can > continue that trend. France is reaching the limits of fission, fusion > is still ellusive, if not illusive, and I don't know of anything that can > provide more total energy than SPS. Let's see some numbers. Until we do, SPS remains speculation. Having more power available in space may not offset the orders-of-magnitude increase in cost, and cost per unit; somehow, it doesn't seem likely. Ground-based Solar is becoming competitive now - and as little as a halving of costs would make it very competitive. Also, what about maintenance costs? Also, have you forgotten that the rectenna array will occupy a great deal of land, as will the fenced-off safety area around it? You know you are going to have problems convincing people that beaming all that energy through the atmosphere is safe - I'm not so sure, myself. What about interference with telecommunications? Also, if you do like astronomy, the static that will come with gigawatts of beamed power, even if far off-band, could easily mean the extinction of radio astronomy (see the 1991 November Physics Today, p. 41, for more on this). Do increased living standards really require increased energy use? Compare Europe and Japan with the U.S. Most energy is used for heating or motion: the most modern conveniences, such as consumer electronics, don't use much energy. Besides, how much more waste heat can the biosphere tolerate? If this isn't a problem, what makes SPS superior to geothermal power? Don't say feasibility and expect me to believe it readily, as sticking two pipes into the ground seems a lot simpler than constructing some gigantic contraption in an alien environment it takes heroic efforts to conduct even the simplest of operations in, where it costs half a billion dollars just to get to. (Sure, you folks say the cost will come down - that's what you said last time, too!) ------------------------------ Date: P From: P To: bb-sci-space@CRABAPPLE.SRV.CS.CMU.EDU Path: crabapple.srv.cs.cmu.edu!cantaloupe.srv.cs.cmu.edu!das-news.harvard.edu!ogicse!uwm.edu!zaphod.mps.ohio-state.edu!cis.ohio-state.edu!ucbvax!CMR.NCSL.NIST.GOV!roberts From: John Roberts Newsgroups: sci.space Subject: Re: Meteor soaks Daytona Message-Id: <9208090131.AA29437@cmr.ncsl.nist.gov> Date: 9 Aug 92 01:31:28 GMT Article-I.D.: cmr.9208090131.AA29437 Sender: daemon@ucbvax.BERKELEY.EDU Organization: National Institute of Standards and Technology formerly National Bureau of Standards Lines: 34 Source-Info: Sender is really news@CRABAPPLE.SRV.CS.CMU.EDU Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU -From: sailor@cellar.org (Rick Emerson) -Subject: Re: Meteor Soaks Datona FL -Date: 6 Aug 92 12:49:15 GMT -Organization: The Cellar BBS and public access system -> From article <1502@tnc.UUCP>, by m0102@tnc.UUCP (FRANK NEY): -> > -----I quote----- -> > A giant wave that drenched Datona FL and caused a lot of damage -> > in July turns out to have probably been caused by a 1 meter -> > meteor! -Yes. A very definative report from a guy in a boat who saw a flash around -the same time the wave hit. I guess that wraps up that issue. -If a 1M rock dropped in at speeds roughly on the order of kilometers per -second, there'd be a darn sight more than a splash. There was an article on medium-size meteorites in Scientific American, but I've completely lost the reference to look it up. (Maybe one in Astronomy in the last year or two as well.) Among the solid meteorites, even the fairly good-sized ones generally stop glowing and coast for a while, reaching a terminal velocity of as little as a few hundred miles per hour before they hit. A one-meter meteorite might be large enough that it would retain considerable impact velocity. A "flash" might be associated with something other than a solid meteorite. At least in California, the seismometers can be used to determine the depth of the epicenter of an earthquake. Can this be done in Florida? John Roberts roberts@cmr.ncsl.nist.gov ------------------------------ End of Space Digest Volume 15 : Issue 089 ------------------------------