Return-path: X-Andrew-Authenticated-as: 7997;andrew.cmu.edu;Ted Anderson Received: from hogtown.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 ; Sun, 27 Jan 91 02:02:41 -0500 (EST) Message-ID: Precedence: junk Reply-To: space+@Andrew.CMU.EDU From: space-request+@Andrew.CMU.EDU To: space+@Andrew.CMU.EDU Date: Sun, 27 Jan 91 02:02:37 -0500 (EST) Subject: SPACE Digest V13 #078 SPACE Digest Volume 13 : Issue 78 Today's Topics: Time change made in Gamma Ray Observatory science briefing and spacecraft showing scheduled at KSC on Jan. 29 (Forwarded) Salyut 7 is still up! Re: space news from Dec 17 AW&ST Re: space news from Dec 17 AW&ST Re: Ultimate Weapon Re: Space Station Weights Administrivia: Submissions to the SPACE Digest/sci.space should be mailed to space+@andrew.cmu.edu. Other mail, esp. [un]subscription requests, should be sent to space-request+@andrew.cmu.edu, or, if urgent, to tm2b+@andrew.cmu.edu ---------------------------------------------------------------------- Date: 24 Jan 91 18:56:24 GMT From: trident.arc.nasa.gov!yee@ames.arc.nasa.gov (Peter E. Yee) Subject: Time change made in Gamma Ray Observatory science briefing and spacecraft showing scheduled at KSC on Jan. 29 (Forwarded) Mike Braukus NASA Headquarters Jan. 24, 1991 202/453-1549 Randee Exler Goddard Space Flight Center 301/286-6256 George Diller Kennedy Space Center 407/867-2468 KSC Release No. 12-91 TIME CHANGE MADE IN GAMMA RAY OBSERVATORY SCIENCE BRIEFING AND SPACECRAFT SHOWING SCHEDULED AT KSC ON JAN. 29 The Gamma Ray Observatory (GRO), which is scheduled to be launched aboard the Space Shuttle Atlantis in April, will be the subject of a science briefing and a showing of the observatory to be held at KSC on Tuesday, Jan. 29, at 10:30 a.m. EST. (Editors please note that this is one half hour later than previously announced.) The Gamma Ray Observatory follows the Hubble Space Telescope as the second in NASA's "Great Observatory" series of astrophysics observatories. GRO's four scientific instruments are designed to study gamma ray sources in the universe. GRO will be the heaviest NASA low earth-orbiting satellite ever deployed from the Space Shuttle, weighing nearly 35,000 pounds. Participating in the briefing will be: P. Thomas Breakfield, Director of Shuttle Payload Operations, Kennedy Space Center John R. Hraster, GRO Project Manager, Goddard Space Flight Center Dr. Donald A. Kniffen, GRO Project Scientist, Goddard Space Flight Center Also participating on the panel and present at the showing of the Gamma Ray Observatory will be the members of the STS-37 flight crew. The astronauts flying aboard Atlantis for this mission are Steven R. Nagel, Commander; Kenneth D. Cameron, Pilot; and Mission Specialists Jay Apt, Linda M. Godwin, and Jerry L. Ross. The briefing will be carried on NASA Select, Satcom F2R, Transponder 13. The V-2 circuits will also carry audio of the briefing and may be dialed directly by calling Area Code 407/867-1220...1240...1260. At the conclusion of the briefing to be held at the KSC News Center, media will be provided transportation to the Payload Hazardous Servicing Facility (PHSF) for the GRO/astronaut photo opportunity. Electronic flash is permitted. However, all lighting equipment must be self contained and battery powered. High pressure sodium (orange) is the available light used in the facility. Appropriate clean room attire will be furnished. In order to maintain payload cleanliness standards, leather or vinyl cases are not permitted within the clean room. Special plastic bags will be furnished to carry camera accessories. Flat, closed-toe shoes are required to be worn; no sandles or high heels. No flame producing devices or tobacco products may be taken into the facility. Media needing accreditation should contact the KSC News Center at 407/867-2468 to arrange for badging. Foreign press not possessing U.S. citizenship must arrange for their accreditation no later than 10 a.m. on Monday, Jan. 28, to allow 24 hours for processing. ------------------------------ Date: 19 Jan 91 04:41:30 GMT From: isis!scicom!wats@uunet.uu.net (Bruce Watson) Subject: Salyut 7 is still up! At about 22hr+change UTC something was sighted passing over Israel. At first it was thought to be a SCUD missile from Iraq. (Seems like something serious is going on over there). My first thought was that they might have been lucky enogugh to see Salyut 7's reentry; but no. CNN reported later that it was the reentry of the booster rocket from a Soviet spy satellite launch 12 hours earlier. The CNN correspondent said that it was going from east to west towards the Mediterranean sea. That is hardly likely. It was in either in a 65 or 81 degree inclination orbit, which at that latitude would take it from south to north or southwest to northeast. Question: why do these reporters get to see something that in 30+ years of observing I've never seen? ------------------------------ Date: Mon, 21 Jan 91 08:40:51 -0500 From: "Allen W. Sherzer" Subject: Re: space news from Dec 17 AW&ST Newsgroups: sci.space In article <6341@exodus.Eng.Sun.COM>: >I also don't think it would cost that much to man-rate one of the more >reliable, smaller launchers such as the Delta, It shouldn't cost anything more. >if NASA were willing to accept a little more risk of launcher failure. Actually, the operational record of the Delta, Titan, and Atlas is BETTER than the operational record of the Shuttle. Realistic Shuttle failure rate estimates show the Shuttle is no safer than an expendable. This calls into question the entire 'man rating' process. Why add all that expense when it doesn't add to safety? Allen -- +----------------------------------------------------------------------------+ |Allen W. Sherzer | America does best when it accepts a challenging mission. | | aws@iti.org | We invent well under pressure. Conversely, we stagnate | | | when caution prevails. -- Buzz Aldrin | ------------------------------ Date: 22 Jan 91 19:11:18 GMT From: sdd.hp.com!wuarchive!julius.cs.uiuc.edu!rpi!mvk@ucsd.edu (Michael V. Kent) Subject: Re: space news from Dec 17 AW&ST In article <9101211347.AA15852@iti.org> aws@ITI.ORG ("Allen W. Sherzer") writes: >In article you write: >>Getting NASA to accept the risk is not your problem. Your problem is getting >>Dan Rather and hence John Q. Public to accept the higher risk. The U. S. >>manned space program almost ceased to exist in 1986 due to 1 failure in 25 >>flights. > >That's not why it happened. For years NASA had been telling people that >the Shuttle was safe. In fact, it was so safe that they could send up >congresscritters and even a teacher. It turned out that not only wasn't >it nearly that safe but it was being run in a manner which made it even >less safe. > >Had NASA been up front with the risks and run a better operation the >Chalanger disaster PR fallout wouldn't have been that bad. After all, >Apollo 1 didn't come close to killing Apollo. Yes, NASA had great claims of the reliability, maintainability, and just plain ability of the space shuttle. But NASA didn't get to build the Space Shuttle they wanted. The Space Shuttle was given the minimum budget to "get the job done." As a result, it doesn't do all of the things NASA wanted a shuttle to do. The politics of the early 70's required bringing everyone under the sun into the Shuttle program to get it built. The politics of the early 80's required an accelerated launch schedule. The politics of the early 90's are affecting the Space Station in the same way. The reason for all of this is that we have a Congress, a public, and a press which has no idea of the complexity and risks of access to space. Apollo 1 didn't kill the Apollo program because the Apollo program was a political one, not a scientific one. We had the Russians to beat. Nothing -- not launch pad fires, nor rocket failures, nor bad weather -- was going to stand in our way of beating those damn Russians. That ambition -- for better or for worse -- is gone forever. Had Apollo 1 occurred today, the result would be very similar to the Challenger aftermath. Michael Kent mvk@itsgw.rpi.edu ------------------------------ Date: 24 Jan 91 02:57:57 GMT From: usc!zaphod.mps.ohio-state.edu!wuarchive!wuphys!ihr@apple.com (Ian H. Redmount) Subject: Re: Ultimate Weapon In article <15923@sdcc6.ucsd.edu> ewa@kingkong.ucsd.edu (Eric Anderson) writes: >In article <1991Jan22.221547.6521@jarvis.csri.toronto.edu> >wayne@csri.toronto.edu (Wayne Hayes) writes: >> >>To make the Earth into a black hole, you would have to >>squeeze it into a ball about the size of a grape. > >A black hole of such small mass is inherently unstable, and will >generally "evaporate" (by a somewhat complex process). The other >poster who mentioned a black hole over Siberia was referring to a >proposition that a black hole of much less mass than the Earth was >responsible for the blast. > It might be useful in this regard to keep some relevant magnitudes in mind. Firstly, to squeeze the earth into a black hole you would have to spin it down as well as compress it. If its angular momentum were conserved in the compression it would form a naked singularity, not a black hole. To form a black hole from a spinning body the ratio of its angular momentum to its mass squared (in units in which Newton's constant G and the speed of light c are both 1) must be less than unity. [See, e.g., ``Gravitation,'' by Misner, Thorne, and Wheeler (Freeman, San Francisco, 1973), p. 878.] For the earth this ratio is of order 500. If you did spin it down before compression, it would form a Schwarzschild black hole of circumference about 5.5cm---about the size of a grape, as stated. Such a black hole is classically stable. Its lifetime owing to quantum-mechanical ``Hawking evaporation'' [Hawking, Nature v. 248 (1974), p. 30] is of order T = (M/Mpl)^3 Tpl , where M is the black-hole mass, Mpl the Planck mass, and Tpl the Planck time. Since an earth-mass hole has M~6x10^(27)g while Mpl~2x10^(-5)g and Tpl~10^(-43)s, the hole's lifetime is of order 3x10^(54)s, or about 3x10^(36) times the present age of the Universe. That's not what is usually meant by the phrase ``inherently unstable'' (8-))! >>The largest black holes postulated, in >>the centre of some galaxies with masses of several million Suns, >>*may* just be big enough to swallow a solar system. > >A black hole doesn't have to be *nearly* as large as a solar system to >swallow it, it just needs sufficient "suck"... :-) > A typical ``supermassive black hole'' of 10^8 solar masses has a Schwarzschild radius of about 2AU, sufficient to mess up the solar system quite nicely. Of course a solar-mass hole, with a Schwarzschild radius of 3km, could do nearly as much damage, even in a distant encounter: At distances beyond a solar radius it would have the same tidal disruptive effects as a passing star (and no chance of ``seeing'' it). The largest black hole I ever heard conjectured was one of 10^15-10^16 solar masses. The Schwarzschild radius of such a hole would be of the order of a kiloparsec. The free-fall time from horizon to singularity in such a hole is of the order of 1000 years [Misner, Thorne, and Wheeler, op. cit., p. 836]: A civilization on a swallowed solar system could rise from prescientific beginnings to the discovery of general relativity in time to discern its fate! 8-) Ian H. Redmount ------------------------------ Date: Thu, 24 Jan 91 10:24:53 -0500 From: "Allen W. Sherzer" Subject: Re: Space Station Weights Newsgroups: sci.space Cc: In article <3213@polari.UUCP> Charles Radley writes: + |There is no point in reproducing all the material here. I was + |interested to note that many of the points I had expressed in + |sci.space are independently raised in the NASA Critique. ++ ...and are adequately dismissed in the LLNL reply. + You are being dogmatic. Some of the NASA answers I agreed with, and +some of the LLNL rebuttals were good too. So which answers NASA gave did you find compelling? +I was particularly +impressed by LLNL actually referencing NASA's own studies in some of +their rebut als, giving the NASA critique the apparance of being +unaware of its own research results. Appearance? What reason do you have to think NASA was AWARE of their own research? They never addressed it in their responce. +If congress appropriated more money it would be interesting to +continue the study. Congress HAS appropriated money to continue. +There simply is no money in the NASA budget to study it. And the budget +continues to shrink. I doubt NASA could impliment it in their current state anyway. Maybe in a few years. As to shrinking budgets, they will be less of a problem because they are spending far less money. ++ BTW, since you ++ saw the critique, can you tell me who wrote it and where they are ++ from? + No idea. Irrelevant anyway, I don't think so. It tells me that the persons who wrote the critique didn't want their names associated with it. +they got no money to continue any +evaluation, unless you can persuade somebody to do it after hours. They have enough money to start prototypeing this year. +But then it would not have the authority of NASA..... No, just the authority of LLNL and the DoE. ++So what. If the approach is good then the politics of the people ++ advocating it are not relevant! + Then why does LLNL waste valuable time with that stuff ? NASA's +charter is technical, not political. Because as Mr. Faering points out the the US alone nature reduces program cost and schedule. I'll admit that Dr. Wood is a very patriotic person (like most DoE people) but I don't see the relevance. +The vu-graphs show no weight or +cost allocations for science. LNNL replies that will be handled ad +hoc after the fact. Compared to the NASA 90 day SEI study, LLNL allocates the same percentage of its budget to science. Because of its compressed schedult we will see more science at any point in time with LLNL than NASA. Even compared to Freedom it would be better. Had this plan been funded when it first came out we would have a large station in orbit doing life science work with huge growth potential for other work one year BEFORE Freedom FEL. +Freedom was expensive & heavy because it included a large up +front science capability. No, Freedom is heavy and expensive because they didn't have a mission for it, let the contractors and centers run open loop, and ignored system integration issues for years. The Reston program office is ONLY NOW (six years into the program) getting a handle on the situation. Now that they know what's going on, NASA wants to move the program office and start all over again. +Crew transportation remains unaccounted for, the LLNL vu-graphs +presented no cost or weight data for that big ticket item. I'm sure there is a lot of stuff unaccounted for. We are only seeing the result of a small study effort. They could use a Soyuz in a pinch so an inexpensive solution exists. + Your space activist newsletter also mentions External Tank and +LLNL in the same paragraph. Why ? Because since we need to start over again we should put more thought into it this time. I like LLNL and think it can work but I may be wrong. It would be nice to have an inexpensive fallback in case I am wrong. +Which is better ? I have no idea. For a small fraction of the cost of Freedom we could prototype several alternatives. Whichever works can then be expanded on. I suspect we will find each alternative has good and bad points (I have always thought a ET could be made into a wonderful dry dock to repair/integrate satellites). +I called External Tank corp and they have minimal technical data, no mass +budgets. I was refering to the SSI External Tank Study. +ET seems oversold. Could well be. I have seen several alternative ideas from LLNL to ET to even stranger things. I'm sure they all won't work. +How can you advocate to our lawmakers that +we should fund such a system ? Because it might work. At least it's worth looking into. + Your efforts are on the verge of permanently grounding the +manned space program. Already PMC for Freedom is gone, which was +its principle purpose. There is no stronger supporter of manned space than I. What is harming manned space is not me but rather our aerospace full employment way of doing things. Consider Freedom. Congress said to NASA: for the next ten years you can have $1.5B growing to $2B; what can you build for that? NASA studied the problem and came back with something like CDSF or ISF at ten times the cost. There is a lot of space work which isn't happening because of this waste. +This is a perfect illustration that it is the CONGRESS, advised by +such as you, whose on-again off-again mood swings are bleeding the +program, yet all you do is blame NASA...... Congress is indeed a large part of the problem but until NASA realizes their share nothing will happen. But remember, sometimes Congress helps NASA out. Sources of Freedom said last July that they didn't want full funding for Freedom. They needed a cut so they could blame the redesign on it. Allen -- +----------------------------------------------------------------------------+ |Allen W. Sherzer | America does best when it accepts a challenging mission. | | aws@iti.org | We invent well under pressure. Conversely, we stagnate | | | when caution prevails. -- Buzz Aldrin | ------------------------------ End of SPACE Digest V13 #078 *******************