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- Date: Fri, 8 Jan 93 05:09:42
- From: Space Digest maintainer <digests@isu.isunet.edu>
- Reply-To: Space-request@isu.isunet.edu
- Subject: Space Digest V16 #019
- To: Space Digest Readers
- Precedence: bulk
-
-
- Space Digest Fri, 8 Jan 93 Volume 16 : Issue 019
-
- Today's Topics:
- *** BUSSARD RAMSCOOP *** (3 msgs)
- DC-1 and the $23M NASA Toilet (2 msgs)
- Justification for the Space Program
- killing the shuttle
- Los Angeles space events
- Marketing SSTO
- Moon Dust For Sale
- Question:How Long Until Privately Funded Space Colonization (2 msgs)
- Questions about SETI
- RTG's on the Lunar Module (2 msgs)
- Shuttle a research tool (was: Re: Let's be more specific) (2 msgs)
- Who can launch antisats? (was Re: DoD launcher use)
-
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- ----------------------------------------------------------------------
-
- Date: Thursday, 7 Jan 1993 12:03:40 PST
- From: Jon J Thaler <DOCTORJ@SLACVM.SLAC.STANFORD.EDU>
- Subject: *** BUSSARD RAMSCOOP ***
- Newsgroups: sci.space
-
- henry@zoo.toronto.edu (Henry Spencer) says:
-
- > Kilogram quantities of antimatter are quite adequate for early interstellar
- > probes, given modest vehicles. I don't have numbers for the antimatter-
- > fuelled ramjet on hand, but it *has* been studied and it looks plausible.
-
- A reality check:
- This is about 13 orders of magnitude larger than the total number of
- antiprotons ever created and stored (about 10**14)
-
- ------------------------------
-
- Date: 7 Jan 93 23:09:42 GMT
- From: Henry Spencer <henry@zoo.toronto.edu>
- Subject: *** BUSSARD RAMSCOOP ***
- Newsgroups: sci.space
-
- In article <93007.120340DOCTORJ@SLACVM.SLAC.STANFORD.EDU> Jon J Thaler <DOCTORJ@SLACVM.SLAC.STANFORD.EDU> writes:
- >> Kilogram quantities of antimatter are quite adequate for early interstellar
- >> probes, given modest vehicles... it looks plausible.
- >
- >A reality check:
- >This is about 13 orders of magnitude larger than the total number of
- >antiprotons ever created and stored (about 10**14)
-
- Reality check right back at you: plot human antimatter production capacity
- versus time. Interesting graph, no? Sure, it's limited right now... but
- it's growing fast.
-
- If we mounted a major effort, we could probably be test-firing antimatter
- rocket engines within ten years. There are *NO* fundamental barriers that
- anyone has been able to find. It's purely a matter of scaling up and
- optimizing the hardware -- the existing accelerators are optimized for
- production of Nobel prizes, not bulk antimatter -- and solving assorted
- straightforward engineering problems of handling and storage. The idea
- has been investigated in depth; no show-stoppers have appeared.
-
- A production setup the size of the Hanford works could make enough
- antimatter to open up the solar system. Interstellar propulsion is
- harder. Kilogram quantities are probably going to have to be made in
- space, not so much for handling reasons (although those aren't trivial)
- as because of the sheer amounts of *energy* needed. It would be a huge
- project, but there's no fundamental problem; we could start designing
- hardware tomorrow if it were urgent enough.
- --
- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology
- -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry
-
- ------------------------------
-
- Date: Thu, 7 Jan 93 17:33:56 -0800
- From: ganderson@nebula.decnet.lockheed.com
- Subject: *** BUSSARD RAMSCOOP ***
-
- Henry Spencer's ramscope talk sparked a question in my small mind. How can
- we talk about the performance of antimatter propulsion without knowing
- the mass fuel ratio? How much hardware does it take to contain a "tank" of
- antimatter (magnetic fields, etc.)? Does anyone have the input required
- for insertion into the rocket equation???
-
- Also, I have seen a graph of anti-mmatter production in the world that
- shows is rising on an exponential curve. (antimater is produced by all
- the big collider folks). Now, suspending my engineering training and
- thinking like a normal liberal economist, the exponential curve showed us
- producing a kilogram of antimatter by the year 2050 or so. That's not
- to long from now....
-
- How do they contain the antimatter before injection into the collider? If
- I remember correctly they have it going around in a racetrack in a holding
- facility, no???
-
- Grant Anderson
- Ganderson@jedi.decnet.lockheed.com
-
- ------------------------------
-
- Date: 7 Jan 93 22:49:08 GMT
- From: Henry Spencer <henry@zoo.toronto.edu>
- Subject: DC-1 and the $23M NASA Toilet
- Newsgroups: sci.space
-
- In article <schumach.726431013@convex.convex.com> schumach@convex.com (Richard A. Schumacher) writes:
- >>Unnecessarily, if so, since the solutions developed for Skylab actually
- >>worked pretty well. (Notably, the Skylab toilet worked.) For rather
- >>longer than a week, too.
- >
- >Uhhh... why didn't NASA just reuse the Skylab toilet on Shuttle?
-
- Good question. I haven't seen a detailed explanation.
-
- I think the excuse was that the Skylab toilet wasn't suited to use by
- women, because it assumed anatomy that could urinate and defecate
- separately. This has always struck me as the sort of problem a good
- engineer could solve easily in any of several ways.
-
- >One gets the impression that the number of competent people
- >at NASA fell below critical mass quite some time ago...
-
- A better way to put it, I think, is that contractor profits and "new
- technology" now get priority over building something that works. It's
- a fairly predictable result of no longer having a plan or a deadline.
- --
- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology
- -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry
-
- ------------------------------
-
- Date: 7 Jan 1993 22:37:08 GMT
- From: "Michael F. Santangelo" <mike@starburst.umd.edu>
- Subject: DC-1 and the $23M NASA Toilet
- Newsgroups: sci.space
-
- matthew@phantom.gatech.edu (Matthew DeLuca) writes:
-
- >In article <schumach.726431013@convex.convex.com> schumach@convex.com (Richard A. Schumacher) writes:
-
- >>Uhhh... why didn't NASA just reuse the Skylab toilet on Shuttle?
-
- >Probably because nobody wanted to go to Australia and pick up all the pieces.
-
- >:-)
-
- Oh, that was cruel. :-)
-
- But, let me ask (since I don't know the specifics): how well did the
- Skylab toilet work and what does the new $23M Shuttle toilet do that
- the Skylab didn't do?
-
- There is also a reference to the Gemini program in this thread, what did
- they do?
-
- Thanks.
- --
- -+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- Michael F. Santangelo + Internet: mike@cbl.umd.edu [work]
- Computer & Network Systems Head + mike@kavishar.umd.edu [home]
- Univ MD: CEES / CBL (Solomons Island) + BITNET: MIKE@UMUC [fwd to mike@cbl]
-
- ------------------------------
-
- From: Paul Dietz <dietz@cs.rochester.edu>
- Subject: Justification for the Space Program
- Newsgroups: sci.space,talk.politics.space
-
- Date: 7 Jan 93 20:51:56 GMT
- Article-I.D.: cs.1993Jan7.205156.13655
- References: <C0163t.Mq4@news.cso.uiuc.edu> <1992Dec29.181813.11510@unocal.com> <jfelder-070193115431@latvia.lerc.nasa.gov>
- Distribution: usa, world
- Organization: University of Rochester
- Lines: 99
- Sender: news@CRABAPPLE.SRV.CS.CMU.EDU
- Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU
-
- In article <jfelder-070193115431@latvia.lerc.nasa.gov> jfelder@lerc.nasa.gov (James L. Felder) writes:
-
- >O.K., I just started following this group today, and already I see one of
- >my favorite topics up for vorciferous debate, so I'll just wade in here. I
- ...
- >Premise 1. We live on a finite planet with finite resources.
- >
- >Premise 2. Our technological society is highly dependent on resources that
- >are being used up faster than they can be replaced.
- >
- >Premise 3. Economists seem to insist that we must continue to grow to
- >increase our standard of living, and the public and politicians seemed to
- >have bought into this premise. For proof one only has to look at the last
- >election to see cries that we are "loosing the American Dream" because we
- >are not better off than our parents held up as worthy compaign issues. The
- >strong implication is that an ever increasing, I would hazard
- >materialistic, standard of living is something we must all strive for.
- >
- >Premise 4. We will not stumble across some unlimited sources of energy
- >(fusion) or materials (say a way to mine the earths core) here on earth.
- >
- >Conclusions. Energy and materials will become increasingly hard to obtain,
- >and that eventually the net energy and material production will decline
- >below what is required to maintain some existing standard of living.Unless
- >we find a way to circumvent the limited resources of our planet, we as a
- >technologically advanced society will cease to exist. People will continue
- >to exist, but society will not be as we know it. I do not know the time
- >frame, nor care to hazard a guess, but the end seems to me to be
- >unavoidable.
-
-
-
- There are a number of problems with this argument...
-
- "We live on a planet with finite resources"
-
- Finite does not mean limited. First, the amount present may be so
- large as to be effectively unlimited. Fertile nuclear materials
- (U-238 and Th-232) fall into this class. Second, aside from
- nuclear uses, elements are not consumed in use, they merely become
- less concentrated. The free energy required to extract materials
- goes as the log of the dilution (higher in practice, but practice
- changes).
-
- "Resources are being used up faster than they are being replaced"
-
- That a resource is limited and not renewable matters only if its
- is very hard to replace with some substitute. Fossil fuels are
- an example -- there is no reason why we should not be able
- to survive indefinitely without them, if some other source of
- energy is available.
-
- [paraphrased] "Growth is necessary to avoid social calamity"
-
- Then we are in big trouble, since growth in resource use cannot
- continue forever. For example, if energy use grows 1%/year,
- then in 10,000 years we are consuming the entire power output
- of the observable universe.
-
- In the short term, however, there is no reason why resource use
- on earth cannot be increased. There is no reason why we could
- not supply several times the current population with several times
- the current US per capita energy consumption indefinitely.
-
- "No inexhaustible energy source on earth"
-
- At least two are already in the engineering stages (solar and fission
- breeder).
-
- "Too Expensive!" you may say. Well, now, yes, but manufacturing
- productivity increases about 3%/year. It gets cheaper to make things.
- Moreover, if we had to make a lot of solar collectors or nuclear
- reactors, economies of scale would drive costs down still further.
- And it's a lot easier to start down a learning curve when you can
- build smallish things on the ground rather than enormous things in space.
- Realize that the current world output of PV modules would take
- more than a century to make enough to cover one 10 GW powersat.
- Space colonization schemes are implicitly assuming big productivity
- increases.
-
- "If we don't go now, resources will be too expensive"
-
- This "window of opportunity" argument falls apart under close
- examination. Resource prices have typically fallen over time, even as
- richer deposits have been exhausted. Moreover, a space program uses
- relatively little in the way of natural resources. What it does use a
- lot of is labor, talent and knowledge.
-
- Look at the price of a shuttle orbiter. It costs more than its own
- weight in gold. The cost of the elements and energy that do go into
- its manufacture is a piddling small fraction of its total cost. The
- same is true of an airliner. The raw aluminum in a 747, for example,
- would cost perhaps a quarter of a million dollars.
-
- Increased raw material prices would only make a space program *more*
- feasible, by increasing the potential profit.
-
- Paul F. Dietz
- dietz@cs.rochester.edu
-
- ------------------------------
-
- Date: 7 Jan 93 22:54:02 GMT
- From: Henry Spencer <henry@zoo.toronto.edu>
- Subject: killing the shuttle
- Newsgroups: sci.space
-
- In article <ewright.726434023@convex.convex.com> ewright@convex.com (Edward V. Wright) writes:
- >>Unlike Allen, I am completely convinced that killing Shuttle now will
- >>not cause any money to be reprogrammed to his pet schemes.
- >
- >So am I. I am also completely convinced it would wipe out
- >a major political base opposed to alternative launchers.
-
- You don't get rid of civil servants and politically-powerful contractors
- that easily. If you wipe out the Imperial Deathstar, they'll only start
- building another one.
- --
- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology
- -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry
-
- ------------------------------
-
- Date: 06 Jan 93 19:49:56
- From: David.Anderman@ofa123.fidonet.org
- Subject: Los Angeles space events
- Newsgroups: sci.space
-
- OASIS, a chapter of the National Space Society
- Schedule of Events
- Winter, 1993
- Call 310/364-2290 for updates
- -
- January 9 (Saturday) 7pm: Reception for special guest: space
- artist and raconteur Christopher Butler will present a review
- of: "1992 - the Year in Space". Also invited: special mystery
- guest. Location: 3136 E. Yorba Linda Blvd., #G14, Cedar Glen
- Apts., Fullerton.
- -
- January 30 (Saturday) 7pm: "Galileo at Earth: Even Better the
- Second Time Around", presented by Robert Gounley, Engineer,
- Project Galileo. To be held at the Von Karmann Auditorium, Jet
- Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena.
- -
- February 12-13: CalSEDS '93: The CSDC Annual Conference. To be
- held at the Pasadena Hilton Hotel.
- -
- February 20 (Saturday) 7pm: Chapter meeting with invited JPL
- project engineer. To be held at 293 E. Ohio Street, #1,
- Pasadena.
- -
- March 13 (Saturday), 7pm: Chapter meeting. Special guest to be
- announced. To be held at 3525 Sawtelle Blvd., #210, (Western)
- Los Angeles.
-
- --- Maximus 2.01wb
-
- ------------------------------
-
- Date: Thu, 7 Jan 1993 21:07:53 GMT
- From: "Edward V. Wright" <ewright@convex.com>
- Subject: Marketing SSTO
- Newsgroups: sci.space
-
- In <C0H7s7.L14@techbook.com> szabo@techbook.com (Nick Szabo) writes:
-
- >Cleary, we do not want to do SSTO like we did STS. I suggest
- >SSTO strategy should be very different, almost the opposite
- >of the strategy used for STS. STS combined astronaut and
- >satellite launching; there should be two very different SSTO
- >vehicles for these very different markets.
-
- Different vehicles, yes. But different vehicles may mean
- two versions of the same design, like the passenger and
- cargo versions of the 747.
-
- >Shuttle was designed and built by a commitee from NASA and the DoD
- >for the vague, sweeping purpose of lowering launch costs;
-
- No, it had a host of vague, sweeping purposes. :-) Lowering
- launch costs was only one of them. And, in the end, not
- even the most important.
-
-
- >SSTO should be designed not to lower launch costs for everybody, but
- >to provide large service improvements to specific markets, for example
- >reducing the cost and increasing the reliability of delivering
- >satellites to orbit.
-
- The problem is, we don't know what the markets are. Rather, we
- know what markets exist for payloads at $10,000 per pound, but
- we don't know what the markets will be at $100 per pound. If
- you tie your design too closely to current satellites, you may
- end up with a white elephant. Better to design for a general
- class of payloads.
-
- >Shuttle was a single design centrally planned; SSTO should
- >come in several competing varieties.
-
- Agreed. Although the first SSTO will be a single design,
- by definition, if it's successor it will invite competition,
- some of which may be better than the original. Personally,
- I think it unlikely (though not impossible) that Delta Clipper
- will become the DC-3 of space. More likely the Ford Trimotor.
-
-
- >STS was an entire "system" that needed new launch pads
-
- So were the first jetliners, which required every airport
- in the US to be rebuilt. (SSTO won't require anything on
- that scale, however.)
-
- >a satellite-launching SSTO should be designed around current
- >comsat/upper stage pairs;
-
- A risky strategy. Not only are new markets likely to
- develop when the costs drop, but old markets can evaporate
- if current satellites/stages are changed or cancelled. A
- better model is the military or civilian cargo plane. It's
- not designed to carry a certain type of truck (although a
- need like that might determine its maximum payload). It's
- designed to carry any payload, generally, that meets certain
- weight and volume limitations. If a cargo requires special
- accomodations -- such as refrigeration -- those are handled
- by additional equipment, rather than the vehicle itself.
-
-
- >Alas, currently the program is headed in direction of the
- >swamp which bogged down the Shuttle, with strong lobbying
- >for NASA to take over the project as a new Clinton start-up.
-
- I haven't heard about this and hope it isn't true.
-
- >This is great politically -- I came up with this idea well
- >before the election, when it first looked like the Democrats
- >had a fighting chance -- but it could be a disaster functionally,
-
- If you substitute "would" for "could," you'd be right on.
-
- >Astronauts either have better
- >things to do, or nothing at all, in which case ferget 'em.
-
- Even worse, if an astronaut gets killed, you have to shut
- down everything for two years while you find Someone To
- Blame. Whatever you do, don't call the crewmembers astronauts!
-
-
- >Which market should SSTO go for? Clearly if there are several
- >SSTOs for several different purposes, there is no one answer.
- >So far, the replacement of STS has been a major goal. However,
- >the astronaut market has a serious drawback.
-
- Not astronaut market, damn it, passenger. Passenger. If the
- passengers happen to NASA employees, so what? NASA employees
- fly on business all the time. That doesn't make them "aeronauts."
-
- >For example, two competing astronaut SSTOs could provide commercial
- >astronaut services to a wide variety of government space agencies,
- >including many countries that currently have no access to spaceflight
- >other than via government agencies of Russia or the U.S.
-
- Why limit it to government space agencies? If Hughes has
- a satellite it wants to repair or salvage, who knows more
- about the design, Hughes or NASA? And if John Denver wants
- to go into space, sell him a window ticket for a premium
- and put the guy from NASA in the back. ;-)
-
-
- >Given the vast market potential of large cost/lb. reductions,
- >we should concentrate far more on making SSTO launch
- >cost reduction a technical reality, and far less on add-ons
- >such as satellite repair, astronaut capsules, etc. The goal is to
- >_reduce_ costs, not to drive up costs by adding on side paraphanalia.
-
- If you're trying to convince a very skepical, conservative
- investor, sure. But realistically, if that's the only focus
- of your business plan, you've missed the big picture, because
- that's not the way markets work. Airplanes made it possible
- to build Las Vegas in the dessert. You have to allow for
- things like Las Vegas in space. (Although it's a bad idea
- for the airplane manufacturer to try to build its own Las
- Vegas. That was one of NASA's mistakes.) And if you're
- trying to build public support, you need to talk about flashy
- things like Las Vegas, rather than mundane stuff like air mail.
-
- ------------------------------
-
- Date: Thu, 7 Jan 1993 20:00:16 GMT
- From: fred j mccall 575-3539 <mccall@mksol.dseg.ti.com>
- Subject: Moon Dust For Sale
- Newsgroups: sci.space,sci.astro,alt.sci.planetary
-
- In <1993Jan7.172032.2895@magnus.acs.ohio-state.edu> bmartino@magnus.acs.ohio-state.edu (Bob Martino) writes:
-
- > A truly simple calculation.
-
- > (A) Determine the mass of all moon rocks recovered. (use a
- > REAL unit like kilograms, please)
- > (B) Determine the total cost of the Apollo program. (Probably
- > should include the cost of Gemini also)
- > (C) Divide (A) into (B) to arrive at the figure.
-
- > Any questions? :-)
-
- Yes. Proof the required assumption for the simple calculation given
- above; i.e., that the sum total and purpose of the Apollo program was
- ONLY to return those rocks, and that nothing else of value of any kind
- was gained for the money. ;-)
-
- --
- "Insisting on perfect safety is for people who don't have the balls to live
- in the real world." -- Mary Shafer, NASA Ames Dryden
- ------------------------------------------------------------------------------
- Fred.McCall@dseg.ti.com - I don't speak for others and they don't speak for me.
-
- ------------------------------
-
- Date: 7 Jan 93 18:16:05 GMT
- From: Willie Smith <wpns@miki.pictel.com>
- Subject: Question:How Long Until Privately Funded Space Colonization
- Newsgroups: sci.space,talk.politics.space
-
- In article <1ig234INNs78@agate.berkeley.edu> tyersome@toxic (Randall Tyers) writes:
- >In response to this question, a group called the Lunar Society appears
- >to be interested funding space colonization. I would like to know
- >whether they are for real. Does anyone know if this group is
- >legitimate and whether they have any chance of reaching their stated
- >goals?
- >
- >Text of a old message describing this group follows.
- [...]
-
- >
- ><1992Aug24.200917.8618@news.media.mit.edu> jeanie@media.mit.edu
-
- Well, as a charter member of the Lunar Society, I can tell you it
- doesn't exist. I'm not out the $100 I sent in, as Jerry Pournelle
- (and/or his minions) never cashed my check. My wife _is_ out her
- $100, as she had to send in a money order (we have no idea if that was
- ever cashed). Either way we never heard _anything_ from them in
- response, other than a couple of "We haven't gotten fired up yet, but
- we'll be getting to it RSN" type responses to Email queries.
-
- The Lunar Society was a great idea, and a bunch of people were fired
- up about it, but I've only heard vague references to it since I
- dropped my BIX subscription. Jerry (IMHO) went downhill rapidly in
- that era, but I'm told he's on the wagon now, so it's marginally
- possible the Lunar Society exists, is for real, and is nonprofit
- 501(c) or whatever. If so I wish them all the luck in the world, but
- we'll not have anything further to do with them.
-
- On the plus side, the concept of the Lunar Society is what got me
- interested in my Simulated Lunar Teleoperations projects, which is a
- _whole_ lot of fun. Their concepts of low cost (Jerry has bandied
- about numbers like $800M (yes, that's an M) for a lunar colony),
- off-the-shelf hardware, and a real break with the usual gold-plated,
- triply redundant, no holds barred, "mass of the paperwork exceeds mass
- of the vehicle" ways of doing space travel were at the very least,
- refreshing.
-
- Willie Smith
- wpns@pictel.com
- My opinions only!!!
- --
- Willie Smith wpns@pictel.com N1JBJ@amsat.org
- "That's the wonderful thing about crayons, they can take
- you to more places than a starship." Guinan - STNG
-
- ------------------------------
-
- Date: Thu, 7 Jan 1993 21:19:05 GMT
- From: "Allen W. Sherzer" <aws@iti.org>
- Subject: Question:How Long Until Privately Funded Space Colonization
- Newsgroups: sci.space,talk.politics.space
-
- If people want to support hardware development for space colonies, they
- can support the Space Studies Institute. They are a real organization
- and fund real work. They even put out a regular newsletter.
-
- I think they where kind of drifting in the past but the unfortunate
- death of Gerald Oneil seems to have galvanized them. Donations can
- be sent to:
-
- Space Studies Institute
- PO Box 82
- Princeton NJ 08540
-
- For $25 per year you become an associate and get their newsletter. For
- $100 you become a Senior Associate and get extra stuff. I am a Senior
- Associate.
-
- Other good organizations are the National Space Society and the
- Space Frontiere Foundation.
-
- Allen
-
- --
- +---------------------------------------------------------------------------+
- | Allen W. Sherzer | "A great man is one who does nothing but leaves |
- | aws@iti.org | nothing undone" |
- +----------------------107 DAYS TO FIRST FLIGHT OF DCX----------------------+
-
- ------------------------------
-
- Date: Thu, 7 Jan 93 17:40:57 -0800
- From: ganderson@nebula.decnet.lockheed.com
- Subject: Questions about SETI
-
- In reponse to Tim Roberts...
-
- This is no flame...Look up the "Drake Equation" in a reference book. This
- is a nifty little equation that calculates the number of civilizations we
- may "hear" while looking for them. One variable within the equation
- is the amount of time a civilization is at or around our technology level
- and therefore would be radiating messages (we sent one out into space in
- the '70s(?) from Puerto Rico) in such a way that our technology would be
- able to "hear" and perhaps comprehend. The only catch is that any
- variable in the equation that turns out to be zero makes for a pretty
- futile search. :-) Don't tell Congresspersons that!!!
-
- Only partially related to you question is a quote from the "Calvin & Hobbes"
- comic strip that has Calvin Saying, "Sometimes I think that the surest sign
- that intelligent life exists in the universe is that none of it has tried to
- contact us." :-)
-
- One final note: You stated that LOTS of money was being spent on SETI.
- Remember, this is space stuff, LOTS doesn't get combined with the word
- money until you are above $100,000,000 per year (a billion here, a
- billion there and pretty soon your talking about real money...) The SETI
- numbers are $100,000,000 over the ten year life of the program.
-
- [I KNOW I'm going to get flamed on that last paragraph....]
-
- Grant Anderson
- Ganderson@jedi.decnet.lockheed.com
-
- ------------------------------
-
- Date: 7 Jan 93 20:52:50 GMT
- From: Dave Michelson <davem@ee.ubc.ca>
- Subject: RTG's on the Lunar Module
- Newsgroups: sci.space
-
- In article <1993Jan7.144516.20330@cam-orl.co.uk> dg@cam-orl.co.uk (Dave Garnett) writes:
- >Peering at a cut-away drawing of the Lunar Module the other day
- >I noticed what appears to be a Radioisotope Thermal Generator
- >mounted on the outside low down.
- >
- >Was this intended to power some experiment - I don't think
- >that they generate very much power (order 80 watts ?)
- >
-
- Yes. It powered the Apollo Lunar Surface Experiment Package (ALSEP).
-
- ------------------------------
-
- Date: 7 Jan 93 22:56:11 GMT
- From: Henry Spencer <henry@zoo.toronto.edu>
- Subject: RTG's on the Lunar Module
- Newsgroups: sci.space
-
- In article <1993Jan7.144516.20330@cam-orl.co.uk> dg@cam-orl.co.uk (Dave Garnett) writes:
- >What are the radiation hazards (to the crew) associated
- >with such a thing, as I understand that they comprise an
- >unshielded lump of plutonium ?
-
- The radiation hazard from plutonium 238 is insignificant; it's pretty much
- a pure alpha emitter, and human skin stops alpha particles completely. (A
- sheet of paper will do likewise.) You don't want to eat the stuff, but so
- long as it stays put, no sweat.
- --
- "God willing... we shall return." | Henry Spencer @ U of Toronto Zoology
- -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry
-
- ------------------------------
-
- Date: 7 Jan 93 19:56:58 GMT
- From: Francois Yergeau <yergeau@phy.ulaval.ca>
- Subject: Shuttle a research tool (was: Re: Let's be more specific)
- Newsgroups: sci.space
-
- In article <C0Hun4.13t@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
- >Actually, it is not at all uncommon for airlines to lease planes complete
- >with crews,
-
- NASA could consider leasing shuttle services if a provider were
- available; but there's none, and with orbiters at $1.5 billion a pop,
- plus gigadollar infrastructure, none is likely to appear out of thin
- air. With shuttle costs at their astronomical levels (even if reduced
- 30% by private industry's magic wand), NASA would likely be the major,
- if not only, customer. A would-be shuttle service provider would want
- a multi-year commitment for a fairly large number of launches before
- investing, which Congress will not make easy. So the basic reality of
- today is that either i) NASA flies the shuttles, or ii) they stay on
- the ground.
-
- >or to contract with specialists for support services like
- >maintenance.
-
- NASA does that too: spent SRBs are send back to Utah for refurbishing;
- the orbiters are sent to Palmdale for their mid-life
- maintenance/upgrade; and there's probably an impressive number of
- Rockwell/Thiokol/you-name-it employees involved directly in shuttle
- operations. But NASA remains the maitre d'oeuvre, probably for the
- reasons stated above.
-
- --
- Francois Yergeau (yergeau@phy.ulaval.ca) | De gustibus et coloribus
- Centre d'Optique, Photonique et Laser | non disputandum
- Departement de Physique | -proverbe scolastique
- Universite Laval, Ste-Foy, QC, Canada |
-
- ------------------------------
-
- Date: Thu, 7 Jan 1993 21:11:20 GMT
- From: "Allen W. Sherzer" <aws@iti.org>
- Subject: Shuttle a research tool (was: Re: Let's be more specific)
- Newsgroups: sci.space
-
- In article <1993Jan7.195658.8028@cerberus.ulaval.ca> yergeau@phy.ulaval.ca (Francois Yergeau) writes:
-
- >NASA could consider leasing shuttle services if a provider were available;
-
- Providers are available. NASA has turned them down.
-
- >but there's none, and with orbiters at $1.5 billion a pop,
- >plus gigadollar infrastructure,
-
- 1. Don't compare govenrment costs with private ones. The private ones
- will be far lower.
- 2. Getting money isn't a problem if the market is there.
-
- >air. With shuttle costs at their astronomical levels (even if reduced
- >30% by private industry's magic wand), NASA would likely be the major,
- >if not only, customer.
-
- They sell the services to NASA. So what?
-
- >A would-be shuttle service provider would want
- >a multi-year commitment for a fairly large number of launches before
- >investing,
-
- Like what DoD did with Titan IV or NASA did to build Shuttle in the
- first place. Not a problem, it happens all the time.
-
- >today is that either i) NASA flies the shuttles, or ii) they stay on
- >the ground.
-
- Since NASA has explicitly refused to even think about proposals, this
- statement cannot be considered accurate.
-
- Allen
-
- --
- +---------------------------------------------------------------------------+
- | Allen W. Sherzer | "A great man is one who does nothing but leaves |
- | aws@iti.org | nothing undone" |
- +----------------------107 DAYS TO FIRST FLIGHT OF DCX----------------------+
-
- ------------------------------
-
- Date: Thu, 07 Jan 93 20:35:33 GMT
- From: Doug Mohney <sysmgr@king.eng.umd.edu>
- Subject: Who can launch antisats? (was Re: DoD launcher use)
- Newsgroups: sci.space
-
- In article <ewright.726433353@convex.convex.com>, ewright@convex.com (Edward V. Wright) writes:
- >In <1993Jan06.212430.15120@eng.umd.edu> sysmgr@king.eng.umd.edu (Doug Mohney) writes:
- >
- >>>Attacking a US carrier battle group is going to raise tensions
- >>>a bit anyway, don't you think?
- >
- >>Use of one or more nuclear weapons is going to invite an escalation which the
- >>attacking force will not wish to solicit, due to the stigma attached to them.
- >
- >Oh? Suppose you see two headlines in the New York Times.
- >
- >One says, "6000 sailors perish in sinking of US carrier group."
- >
- >The other says, "Nuclear weapon used to disable unmanned satellite."
- >
- >Which would set your blood to boiling more?
-
- "Well, if they're crazy enough to use them in orbit, when will the get around
- to using them on us?"
-
- You're being silly. If you're going to treat the nuke as "just another
- weapon" you don't need the Clancyesque plot. Just nuke the friggin' carrier
- and be done with it. It's only full-scale war, after all, right Ed?
-
- >>It is likely we have a quick-launch replacement capability, either through
- >>air breathing mysterious aircraft or (more likely) derivative ballistic
- >>missile capability, on land and at sea.
- >
- >The US Navy considered coverting one Poseidon missile on each
- >submarine to a satellite launcher, however this was never carried
- >out. (Unless it was done in secret.) However, no US SLBM or ICBM
- >has the payload capacity to replace a large communications or
- >reconnaissance satelite.
-
- Of course not, but attacking com-sats is a different problem than attacking a
- low-orbit KH-11.
-
- It is not for nothing DARPA has a love with microsats and ways to get them
- quickly into orbit. And what DARPA is doing is in the sunshine.
-
- >>Sure it didn't. However, the UN voted to remove Iraqi troops by the use of
- >>force and thereby did so accordingly.
- >
- >No, the US voted to remove Iraqi troops and the United States did so
- >accordingly. (With help from some of our allies, yes, but no serious
- >observer suggests that we would have failed without that help.)
-
- Of course. So why did we get the UN to rubber stamp it first? C'mon Ed, stop
- helping me out here. We really didn't NEED to get the UN's blessing, did we? So
- why did George Bush spend all that time on the phone calling up his world
- leader buddies soliciting support ?
-
- >Besides, your claim was that "international public opinion" would
- >*prevent* nations like Iraq from making hostile acts.
-
- Prevent a degree of hostile acts. Why didn't the Iraqis use chemical weapons
- against allied forces in Desert Storm?
-
- I have talked to Ehud, and lived.
- -- > SYSMGR@CADLAB.ENG.UMD.EDU < --
-
- ------------------------------
-
- End of Space Digest Volume 16 : Issue 019
- ------------------------------
-