Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from beak.andrew.cmu.edu via trymail for +dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl@andrew.cmu.edu (->+dist+/afs/andrew.cmu.edu/usr11/tm2b/space/space.dl) (->ota+space.digests) ID ; Thu, 22 Mar 90 01:32:13 -0500 (EST) Message-ID: Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Thu, 22 Mar 90 01:31:42 -0500 (EST) Subject: SPACE Digest V11 #171 SPACE Digest Volume 11 : Issue 171 Today's Topics: More space station news... Viewing the Space Shuttle landing Re: Geostationary orbit Re: Commercial Titan/Intelsat Launch Failure Re: Shuttle Escapes Re: What was Challenger really up to? Re: Coilgun on a 747 - supplies to orbit at $20/lb? ---------------------------------------------------------------------- Date: 20 Mar 90 14:58:18 GMT From: zaphod.mps.ohio-state.edu!wuarchive!kuhub.cc.ukans.edu!honors@think.com Subject: More space station news... Thought my fellow netters would be interested in this report on the Incredible Shrinking Violet Space Station, ExpensiveDom... These stories came off the AP wire today (3/19/90): ***** Report: NASA Investigators Conclude Space Station Plans Flawed NEW YORK (AP) Q The planned space station Freedom cannot be built as designed because its thousands of parts would begin breaking down even before the station was fully assembled in space, according to a published report. The New York Times said in today's editions that the National Aeronautics and Space Administration still was not sure exactly how to remedy the design flaws in the $30 billion space station. The project is to be the centerpiece of plans to have astronauts explore the solar system. The problem was discovered by a team of NASA investigators early this year who calculated the likelihood of the station's thousands of parts failing in a given time period.They found that even before construction is three-quarters complete, it would be time for major maintenance and overhaul of the space station. Construction is expected to take five years. NASA's plans call for the station to serve as an orbiting outpost from which astronauts would conduct a variety of scientific studies and explore the solar system. So far, almost $4 billion has been spent on design studies and other preliminary work.If built according to plan, the space station would have more than 5,500 external parts that would need to be replaced if they failed, investigators concluded. Officials calculated the likelihood of failure, the time required to replace the parts, and determined that the station would need about 2,200 hours of maintenance each year by astronauts working in space suits. Space walks entail risks that range from radiation exposure to flying space debris. ***** NASA Says It's Working to Resolve Space Station Maintenance Problem By HARRY F. ROSENTHAL Associated Press Writer WASHINGTON (AP) Q NASA said today that its engineers have worried for years that astronauts will have to spend too much time in the harsh environment of open space to repair and maintain the space station that is set for construction in the mid-90s. Agency officials were preparing a response to a front-page article in the New York Times today that said the station can't be built as designed "because its vast array of parts would start to break down before the station was completed." The first elements of the $30 billion station are to be carried into orbit beginning early in 1995 and completion is scheduled for 1999. The Times said NASA investigators found that construction would be only 60 percent to 70 percent complete before preventive maintenance would have to begin. The Times said investigators concluded that, if built according to plan, the space station would have more than 5,500 external parts that would need to be replaced if they failed. That would require space walks, or what NASA calls EVAs, short for extra-vehicular activity. "In terms of the program addressing EVAs, that is not a new thing; it's not a new problem that has suddenly been discovered," said space station spokesman Mark Hess.The Times said such space walks would total 2,200 hours for maintenance, but Hess said that estimate includes a lot of time in which astronauts would not actually be outside of the relative safety of the station. Another spokesman, James McCulla, said EVA time "is a matter that space station designers have been working on for years." He said that working out methods to cut down the EVA time is an integral part of design review activities "and therefore will be an important matter to be worked on for days to come." ***** Interesting, no? Makes you long for the days when things could be done simply and easily at the space agency... Travis Butler Argue ideas, HONORS@kuhub.cc.ukans.edu not sources ------------------------------ Date: 20 Mar 90 21:12:31 GMT From: skipper!shafer@ames.arc.nasa.gov (Mary Shafer (OFV)) Subject: Viewing the Space Shuttle landing [Sorry--I'm a little late with this. At least they haven't launched yet. MFS] There are four ways to see the Shuttle landing at Edwards AFB, listed in order of restrictiveness of access. 1. The public viewing area on the lakebed. Take Hwy 14 to Avenue F and follow the signs. This area is opened about 2 days before the scheduled touchdown. The viewing area is an unimproved area so don't expect many amenities. I think that there are sanitary facilities and that food and drinks can be purchased. It's suggested that you bring food and water Nothing is required for access to this area. (I've never been to this area, so I can't speak from personal knowledge.) 2. The hillside viewing area. This is on the hillside, just above Ames-Dryden, and requires a special pass. This pass is good for one vehicle, with any number of passengers. You can't enter the Ames-Dryden complex but you can walk down the hill to the cafeteria and the giftshop, etc. More amenities, including radio transmissions from the Shuttle and JSC. Some of us believe that this area has the BEST view of the landing. These passes can be obtained by writing, as detailed below. Ames-Dryden employees can also obtain them. 3. Official guest. Access to the Ames-Dryden complex. You get to watch the landing from the ramp, which is right on the lakebed. (The Shuttle lands some distance away, depending on which runway it uses.) The crew speaks to the crowd just before they return to JSC. There are special aircraft displays (including the SR-71, F-15, F-18, X-29, etc.) in the hangars. The radio transmissions are broadcast. You can write, as detailed below, to obtain these badges and parking permits. Employees are allotted one car pass and four badges for family and friends. 4. Distinguished guest. As 3 above, with the viewing being done from the complex roof. This group includes the families and guests of the astronauts and notables (of a variety of types--Dick Rutan was at a recent landing) in the aerospace community, etc. These people are invited by NASA management and the list is fairly small. To obtain a hillside pass or official guest badges, write to: NASA Ames-Dryden Flight Research Facility Attn: Public Affairs Office P.O. Box 273 Edwards, CA 92523-5000 Do this early, because there is a limited amount of space. If you get these and then discover that you can't attend, please try to pass them on to someone else who can use them. Incidently, there is _no_ charge for any of these. Come see the Shuttle land--it's great. -- Mary Shafer shafer@skipper.dfrf.nasa.gov or ames!skipper.dfrf.nasa.gov!shafer NASA Ames Dryden Flight Research Facility, Edwards, CA Of course I don't speak for NASA ------------------------------ Date: 20 Mar 90 23:22:27 GMT From: zaphod.mps.ohio-state.edu!swrinde!cs.utexas.edu!news-server.csri.toronto.edu!helios.physics.utoronto.ca!physics.utoronto.ca!neufeld@tut.cis.ohio-state.edu (Christopher Neufeld) Subject: Re: Geostationary orbit In article <1990Mar20.205833.10254@brutus.cs.uiuc.edu> zweig@cs.uiuc.edu writes: >cjs@sppy00.UUCP (Christopher Schaller) writes: > >>Quick question! >>How high does a satellite have to be to atain geostationary orbit > >A satellite on the ground has a very nice geostationary orbit. > >>geosynchrous orbit? > >About 22,000 miles. > >> Chris. > >-Johnny For both geostationary and geosynchronous orbits, other than the trivial example given by Johnny, the height is about 36000 km. A geostationary orbit is an orbit over the equator, moving in the same direction as the Earth rotates, at 36000 km. An observer on the ground can look up and always see the orbiting body in the same position in the sky. A geosynchronous orbit is any orbit at 36000 km which does not move in the opposite direction to the Earth's rotation. For instance, if I moved straight up 36000 km, and then acquired the correct velocity due East, I would be in a geosynchronous orbit going between about 47 degrees North and South latitudes. Seen from the ground, I would appear to move in a figure-eight pattern, but one which is always in the same position in the sky. So, geostationary orbit is a 24 hour (or is it 23h56m4.09s?) orbit which follows the equator, while a geosynchronous orbit is a 24 hour orbit which does not necessarily follow the equator. -- Christopher Neufeld....Just a graduate student | "You are looking at, neufeld@helios.physics.utoronto.ca | ze virld's FIRST, cneufeld@pro-generic.cts.com Ad astra! | nuclear - magnet!" "Don't edit reality for the sake of simplicity" | Siegfried of KAOS ------------------------------ Date: 19 Mar 90 16:15:48 GMT From: idacrd!mac@princeton.edu (Robert McGwier) Subject: Re: Commercial Titan/Intelsat Launch Failure From article <1990Mar16.033349.25657@agate.berkeley.edu>, by gwh@headcrash.Berkeley.EDU (George William Herbert): > Yesterdays attempted launch of a commercial Titan III with an Intelsat VI > comsat aboard apparently failed. From sketchy reports, it looks like the > transfer stage did not seperate from the second stage, and the Intelsat VI > My ``Martin Marietta sources" have told me that the seperation computer control code was flawed. The hardware all tested fine on the ground when test software was run. The flight code that was accidentally loaded was designed for a TWO SATELLITE mission. The satellite that was on board was in the second satellite position if there had been two birds on board. The software was looking for a wire to be severed that would have signalled that the first satellite had been successfully ejected. Since there was none, the hardware lockouts could not then successfully be overridden and the software could not be changed from the ground for whatever reason. Probably no receivers and/or no time before the batteries in the final stage give out. Bob -- ____________________________________________________________________________ My opinions are my own no matter | Robert W. McGwier, N4HY who I work for! ;-) | CCR, AMSAT, etc. ---------------------------------------------------------------------------- ------------------------------ Date: 19 Mar 90 21:33:43 GMT From: cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo!henry@tut.cis.ohio-state.edu (Henry Spencer) Subject: Re: Shuttle Escapes In article <19.Mar.90.13:22:53.GMT.ZZASSGL@UK.AC.MCC.CMS> ZZASSGL@cms.manchester-computing-centre.ac.UK writes: >Just how difficult is it to get a reasonably well protected human from >low earth orbit to the ground alive and without a space craft? Is it possible >to lose velocity slow enough that heat shields are not required? In theory it can be done. With a specially-designed deceleration parachute, the deceleration can be done at extreme altitude and the heat loads are within the range that current spacesuits can handle. One would then need a more normal parachute for the final landing. (Actually, I expect one would need a fairly hefty parachute, since suit plus backpack plus etc. add quite a bit of weight.) Nobody has actually flown hardware to test this, mind you, let alone tried it in person. -- MSDOS, abbrev: Maybe SomeDay | Henry Spencer at U of Toronto Zoology an Operating System. | uunet!attcan!utzoo!henry henry@zoo.toronto.edu ------------------------------ Date: 20 Mar 90 00:55:59 GMT From: johnsonr@boulder.colorado.edu (Richard Johnson) Subject: Re: What was Challenger really up to? GILLA@QUCDN.QueensU.CA (Arnold G. Gill) writes: > > I heard the following story from a friend... > > The real cause of the Challenger accident was not O-ring failure as we > are all meant to believe, but rather due to an accidental discharge of the > military laser being carried (illegally) up into orbit, which blasted through > the shuttle and exploded the fuel tanks. That story sounds a lot like the fantasies my friends and I used to come up with when we were 10 years old. You requested serios refutations, but it's difficult to make any such statements about something so sophomoric. All I can do is point out that the so-called evidence is incomplete. It took a long while to find the crew cabin because its hard to find things under even shallow water (otherwise we'd have discovered all shipwrecks of interest by now). I'd also like to know *which* crew member was the supposed laser expert. Simply stating there was "[a] laser expert on board" will only convince those 10 year olds who want to believe something fishy was going on. The bit about erased portions of the cockpit recorder tape is also incomplete. What was supposedly erased, and from *where* in the transcript? I don't thing the much-maligned Christic Institute would even bother with this one. | Richard Johnson johnsonr@spot.colorado.edu | | CSC doesn't necessarily share my opinions, but is welcome to. | | Power Tower.>.Dual Keel.>.Phase One.>.Allison/bertha/Colleen.>.?... | | Space Station Freedom is Dead. Long Live Space Station Freedom! | ------------------------------ Date: 20 Mar 90 04:42:45 GMT From: ogicse!caesar.cs.montana.edu!samsung!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!srcsip!jhereg!wd0gol!newave!john@ucsd.edu (John A. Weeks III) Subject: Re: Coilgun on a 747 - supplies to orbit at $20/lb? In article <1990Mar19.130932.26183@eplrx7.uucp> leipold@eplrx7.UUCP (Walt Leipold) writes: > If you're really launching significant masses (> 20 kg/min?), you could > probably keep the 747 in the air using "mass driver" propulsion. (Now, > all we've gotta do is find a power source for that sucker...) Cold fusion, of course. Something about the size of a wine bottle should do it. Take two just in case... 8-) -john- -- =============================================================================== John A. Weeks III (612) 942-6969 john@newave.mn.org NeWave Communications ...uunet!rosevax!bungia!wd0gol!newave!john =============================================================================== ------------------------------ End of SPACE Digest V11 #171 *******************