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Date: Tue, 22 Dec 92 05:16:17
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V15 #582
To: Space Digest Readers
Precedence: bulk
Space Digest Tue, 22 Dec 92 Volume 15 : Issue 582
Today's Topics:
Acceleration
Breeder reactors
Breeders
Chase planes
DC vs Shuttle capabilities (2 msgs)
Feelings
Justification for the Space Program (3 msgs)
Looking for sci.space archives
Making Orbit '93
misc
STS-48 and "SDI": Oberg vs. Hoagland
Terminal Velocity of DCX? (was Re: Shuttle ...)
Voyager UVS shutdown
Welcome to the Space Digest!! Please send your messages to
"space@isu.isunet.edu", and (un)subscription requests of the form
"Subscribe Space <your name>" 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: Tue, 22 Dec 92 00:46:50 EST
From: John Roberts <roberts@cmr.ncsl.nist.gov>
Subject: Acceleration
-From: gene@wucs1.wustl.edu (_Floor_)
-Subject: Re: Galileo's atmospheric probe
-Date: 17 Dec 92 23:37:51 GMT
-In article <ZOWIE.92Dec16182405@daedalus.stanford.edu> zowie@daedalus.stanford.edu (Craig "Powderkeg" DeForest) writes:
-] If you drop a Timex watch (``takes a lickin' and keeps on tickin'\ '') from
-] a height of 1m onto a cement floor, carefully holding it so it falls flat,
-] and it stops in 1mm, then it underwent 1000G's of acceleration!
- I think there's a bit of a difference here. You're talking about forces
- and accelerations experienced for milliseconds at a time. This probe
- will be experiencing this accleration for several minutes! Things
- can be damaged to prolonged exposure to acceleration!
- Gene Van Buren, Kzoo Crew(Floor), Washington U. in St. Lou - #1 in Volleyball
That applies to things that are somewhat resiliant (like humans with their
limbs not locked), because if deformation continues throughout the period
of acceleration, then the entire body is not really subjected to the full
acceleration. (For another example, putting rubber feet or a springy internal
suspension in a piece of equipment can greatly reduce the maximum shock if
you drop it.)
But other than that, and factors such as prolonged stress on human hydraulic
systems, the greater problem can be with rapid changes in acceleration, which
are of course associated with short bursts of acceleration. (I believe the
usual term for the time derivative of acceleration is "jerk".) These rapid
changes can cause very high internal stresses that are not found with slow,
steady increases in acceleration.
Just as an example, compare your body lying in a bed with a downward
acceleration of one gravity, or being clamped in a device that repeatedly
shakes your body back and forth, with a maximum acceleration of half a gravity.
Which do you think would be likely to place more stress on your body, and
which would be quicker to cause discomfort? :-)
John Roberts
roberts@cmr.ncsl.nist.gov
------------------------------
Date: Tue, 22 Dec 92 02:05:25 EST
From: John Roberts <roberts@cmr.ncsl.nist.gov>
Subject: Breeder reactors
-From: dietz@cs.rochester.edu (Paul Dietz)
-Subject: Re: Breeder reactors (was Re: Justification for the Space Program
-Date: 20 Dec 92 18:53:59 GMT
-Organization: University of Rochester
-In article <1992Dec20.044836.26997@seq.uncwil.edu> session@seq.uncwil.edu (Zack C. Sessions) writes:
->>Speaking of breeder reactors, why doesn't the U.S. have more of
->>them?
->Because they're too damn dangerous.
-Gee, all kinds? Do remember that there are at least 3 fundamentally
-different classes of breeder reactors that we know are workable (fast
-breeders, thermal breeders and spallation reactors). The second of
-these already has instances in commercial use (Canadian CANDU PHWRs,
-and the related Indian PHWRs). These can be operated in the
-thorium/uranium fuel cycle which involves no plutonium, although
-currently they operated as burners with natural uranium.
One concern I've heard concerning at least some of the breeder cycles is that
the fuel produced is more easily converted to bomb-grade material than is the
U238-U235 mix traditionally used in commercial reactors. At the moment, it's
difficult to guarantee that nobody can steal or divert a sufficient quantity
of such a material (if it's widely used) to cause trouble. I believe I've
heard proposals such as deliberately contaminating the fuel with high-level
waste to make it too dangerous for thieves to handle. Do you have any more
information on this aspect? And are there designs where the breeder itself
consumes the fuel it generates?
-With natural uranium currently at $10/lb, and with fossil fuels
-abundant (too abundant, some might say) breeders (as such) don't
-currently have sufficient advantages to overcome political and
-economic obstacles.
How much does uranium sufficiently enriched for use in commercial reactors
cost? (For that matter, how much does U235-depleted uranium cost?)
John Roberts
roberts@cmr.ncsl.nist.gov
------------------------------
Date: Mon, 21 Dec 1992 20:45:53 -0600
From: pgf@srl01.cacs.usl.edu (Phil G. Fraering)
Subject: Breeders
\Session's Answer was too flipant. The reason the U.S. doesn't hav mre
/ooops have more breeder reactors is that the anti-nuke forces won a battle
\in the late seventies and President Jimmy Carter stopped the development
/of them. The arguements given revolved around the proliferation of
\Plutonium that the reactors "breed" and not on the safety of the
/reactors. The nuke power industry was trying to sell them as the answer
\to lmited supplies of nuclear fuel (o.k. expensive supplies) because they
/produce 5 lbs of fuel for every 4 they consume. Unfortunately, the
\plutonium is also a great nuke weapon resource.
From what I've heard, it's the wrong isotope or mixed with such as
to be useless in constructing a nuclear bomb.
Of course, don't let that stop you from freezing in the dark,
yankee...
--
Phil Fraering
"...drag them, kicking and screaming, into the Century of the Fruitbat."
<<- Terry Pratchett, _Reaper Man_
PGP key available if and when I ever get around to compiling PGP...
------------------------------
Date: Tue, 22 Dec 92 00:27:14 EST
From: John Roberts <roberts@cmr.ncsl.nist.gov>
Subject: Chase planes
-From: PHARABOD@FRCPN11.IN2P3.FR
-Subject: Aurora
-Date: 21 Dec 92 16:29:18 GMT
-John Roberts wrote (Wed, 16 Dec 92 07:58:24 EST):
->It's common to have chase planes flying along with an aircraft
->undergoing tests. One of the two Valkyrie supersonic aircraft was
->destroyed when a chase plane crashed into it.
-Thanks for that info. However, does "flying along with" means "chasing"?
-(AW&ST wrote "chasing").
I believe the "chase planes" occasionally used with the Shuttle are
T-38s (T for "trainer"?), which carry no armaments. I don't know the full
history of the term as it applies to aviation - I've just seen it in use.
I think the more agressive term may be "engage".
-Also, was the Valkyrie a "black" aircraft?
Sorry, I don't know. They show it on television now. There are several
programs on the Discovery Channel (a cable TV channel) that regularly
feature military aircraft.
-I apologize for being so skeptical and stubborn, and for my bad knowledge
-of American and/or military aviation words, but I want to be sure...
I suspect the misunderstanding is due to one of those words that's nearly
the same in two languages, but which has slightly different connotation.
Doesn't the French verb "chasser" mean "to hunt"?
John Roberts
roberts@cmr.ncsl.nist.gov
------------------------------
Date: 22 Dec 92 06:31:51 GMT
From: Greg Moore <strider@clotho.acm.rpi.edu>
Subject: DC vs Shuttle capabilities
Newsgroups: sci.space
In article <BzHH37.9r5@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>In article <b-p254n@rpi.edu> strider@clotho.acm.rpi.edu (Greg Moore) writes:
>> Umm, so? Tell me, did you see 3 aircraft landing at the same
>>time, or flying in formation? Did you see baggage transferred between
>>them while in flight? I'm not talking about on the ground, I'm talking
>>about in space...
>
>Why do you assume that "in the air" is a better analogy for "in space"
>than "on the ground" is? Flying aircraft in close proximity is vastly
>harder than doing the same for spacecraft, because of the complex and
>unpredictable behavior of the atmosphere. In-orbit operations resemble
>on-ground operations more than in-flight operations: the environment
>is simple and predictable and you can take your time.
>--
I make the analogy for two reasons. One as you point out may be
invalid.
Let's handle baggage transfer. On the ground, you have gravity
and the surface. You can walk/carry/drive between two planes. In
air, you have to somehow manevour. As you point out, the air itself
makes this tricky. But in space, you don't have something nice like
the ground to use. So, the astronauts have to use MMU's or make
blind leaps between the three crafts.
As for manevouring the 3 craft in close proximity, I partly
agree with you. It is easier than doing it in the air. However,
you do have three craft now all with somewhat different velocity
vectors. I believe that the Intelsat rescue was the first time
both bodies were active in terms of maneuvering.
I'm not saying it can't be done, or that it won't be done.
Simply that some thought and PRACTICE will have to go into it.
Perhaps sea operations are a better example. But I don't think
so.
>"God willing... we shall return." | Henry Spencer @ U of Toronto Zoology
> -Gene Cernan, the Moon, Dec 1972 | henry@zoo.toronto.edu utzoo!henry
------------------------------
Date: 22 Dec 92 07:00:38 GMT
From: Greg Moore <strider@clotho.acm.rpi.edu>
Subject: DC vs Shuttle capabilities
Newsgroups: sci.space
In article <ewright.724956784@convex.convex.com> ewright@convex.com (Edward V. Wright) writes:
>In <b-p254n@rpi.edu> strider@clotho.acm.rpi.edu (Greg Moore) writes:
>
>> Umm, so? Tell me, did you see 3 aircraft landing at the same
>>time, or flying in formation? Did you see baggage transferred between
>>them while in flight? I'm not talking about on the ground, I'm talking
>>about in space. If you recall, my original comment was about in-flight
>>satellite repair.
>
>You're being led astray by words.
>
>Both airplanes and orbiting spacecraft are said to be
>"in flight." That doesn't mean they have anything in
>common, except that neither one is in contact with the
>Earth. We also say that ships and islands are "at sea."
>That doesn't mean that ships and islands have very much
>in common.
>
Gee, thanks for clearing that up to me. And I thought
the space shuttle needed wings so it could fly through the ether.
The key words in your rebuttal are "...neither one is in contact
with the Earth." Exactly. I can't just "walk" from a DC-10 in
flight to a 747. I can't just "walk" from a DC-1 to another
DC-1 in flight either.
I can recall only 1 (possibly 2) examples of astronauts
transferring between craft via EVA. And in that case I believe
the craft were linked. Ever note how careful NASA is when
it sends astronauts on EVA. They make sure they are somehow
securred to the shuttle or the RMS so that they don't accidently
drift off.
I don't doubt that someday we'll see EVA between
non-docked craft. I also don't doubt that we'll see in-orbit
refuelling of cyrogenics. I also don't doubt that we'll see
3 bodies maneuvering within a small space (say less than a couple
of meters between craft). But, I claim it will take lots of
work and lots of practice.
>An orbiting spacecraft is not flying like an airplane.
>There is no air rushing past the wings. It isn't using
>aerodynamics to stay up and isn't using its engines to
>maintain velocity. If it runs out of fuel, it does not
>come crashing back to Earth like an airplane.
>
Gee, and you mean all those Star Trek episodes where
if the engines failed the Enterprise crashed were a bunch
of howie? Gee whillickers.
And speaking of wings, when did wings come into
play. I'm not complaining about wings, or the lack thereof.
I think you've mistaken me for someone else on this net.
>When two spacecraft touch each other, they are not "in
>flight" relative to one another. They are said to be
>"docked," like ships at sea. So, if you want to base
>your analogies on words like this, you should argue that
>the US Navy is the only organization that can navigate
>two ships to the same dock, then transfer fuel from one
>to another.
>
So, Intelsat VI and Endeavour were docked before
it was hard-down in the payload bay? What about when
the astronaut bumped it with the bar? Was that docked?
Or was that in flight relative to each other. I think
NASA would like to know that gee, they were docked, and
tht the Intelsat was NOT set into motion by this contact.
And as for tranfering fuel while under way, my naval
knowledge is less, but I don't know too many groups of people
other than the military that do fuel transfers while in
motion. It's generally a whole lot easier to come to a
dock, or at least anchor in calm water.
(And, even then, it's somewhat easier than in
space since the water will tend to damp your motions if
you bump the other ship.)
>
>> Ayup. And the US Air Force is the ONLY one that regularly does
>>inflight air-refueling. I haven't seen Delta or Virgin Atlantic do it.
>>Remember, again, we are talking about in-orbit, not on the ground.
>
>We aren't talking air-to-air refueling either. In-space refueling
>does not require split-second timing, only hooking up the hoses
>properly.
>
Only. Given the current understanding I have of DC-1,
(and please, correct me wrong if I am) there is no mechanism
for a drogue or probe. The drogue you could argue is part of
the cargo fuel tanks. The probe has to be added to the DC-1
you want to refuel. Now, when designing this, you have to account
for any nudges your drogue may transmit. As you transfer fuel
between craft, your mass changes, which means you have to actively
update your algorithm for active stabilization. If you have a
rigid "arm" for your drogue, you can't have to much movement,
lest you break your "arm". If you use a hose, you need someway
of attaching it. (Either a rigid arm or an astronaut). A hose
introduces other problems related to a change in center of mass.
Now, one way I see around this is to redesign the DC-1
so that two can accomplish a hard-docking of some sort. In
this I mean something studier than a linkage carrying one or
two fuel lines. I make this requirement only because I think
stress on a much smaller arm would be too higher.
>So, what's so special about the ground?
>
It's stable. Things on it tend to find a stable point.
If I happen to lean against a DC-1 on the ground, or even push off
with some force, the worst that happens is I fall down. I don't
drift off. (Before you jump down my throat, no I don't think
the risk of a person drifting off is high at all. However, I do
think the risk of induced motion to be high.)
>
>> No, some people are telling me, DC-1 will do this, do that, and
>>hey, we can add this, we can add that... it's all going to be easy.
>>I'ms aying, "sounds good, but prove it."
>
>Again, I thought that was what we are doing.
>
Sorry, but to me, and some others, it sounds like some
people ahere are trying to skip the prove it step and say, "take
our word for granted."
>What are *you* doing, except standing on the sidelines carping?
>
I'm not insulting people.
And I'm trying to A) get some answers for my own
use. B) Inject a little reality into this world. A reality
where sometimes things don't work the first time. Were some things
may never work. A reality where a person is willing to say,
"Hey, wouldn't it be great if this thing is cheap enough to fly to
the moon!", not "Oh, we just fly over to our on-orbit depot, fuel
up, and fly over. It's a piece of cake."
Trust, me, I'm a big fan of the DC-X and DC-Y programs.
I do have doubts about DC-1 though.
>
>
>
>
>
------------------------------
Date: 21 Dec 92 20:19:32 GMT
From: David.Anderman@ofa123.fidonet.org
Subject: Feelings
Newsgroups: sci.space
None of us here know exactly what the future of the space launch industry will
be. Making blanket statements about the future is an extremely hazardous
business: the only certainly is that the probability of being wrong is high.
SSTO might work; it might not. After a test program that truly demonstrates
the key technologies, we may know whether the SSTO
concept is viable. The question is: do you support a SSTO test
program, or do you believe the concept is so flawed that it is
pointless to test the technologies?
--- Maximus 2.01wb
------------------------------
Date: 22 Dec 92 02:33:53 GMT
From: George Coleman <gcoleman@magnus.acs.ohio-state.edu>
Subject: Justification for the Space Program
Newsgroups: sci.space,talk.politics.space
>for every dollar spent in space there is an estimated 7 dollar return in
> space spin offs.
I have read this many times in nasa releases and every time it struck a sour
chord. If there is that much return on technical research than it sounds like
the market is in great demand. Simple supply and demand would then dictate
that many firms would try to fill this demand. Call me strange but I trust the
market more than I trust press release from a government agency. If this were
realy true than there should be a *private* firm raking in a bundle of money.
To save so time and net space I will knock down the obvious straw man...
The government needs to step in because there is a market failure.
Technology is a common good and free market doesn't have means to
provide common goods.....
Maybe, just maybe private firms have a hard time marketing new advances but
with a 7/1 return they should be able to find a way. Second, if the market
realy can't work the goverment should specialize. Have one agency specialize
in product development and one agency build real, working space ships. NASA
spends way to much time developing new technology instead of mass producing
proven designs.
Ed Colmeman
------------------------------
Date: Tue, 22 Dec 1992 02:41:27 GMT
From: Paul Dietz <dietz@cs.rochester.edu>
Subject: Justification for the Space Program
Newsgroups: sci.space,talk.politics.space
In article <1992Dec22.023353.10922@magnus.acs.ohio-state.edu> gcoleman@magnus.acs.ohio-state.edu (George Coleman) writes:
>>for every dollar spent in space there is an estimated 7 dollar return in
>> space spin offs.
>
>I have read this many times in nasa releases and every time it struck a sour
>chord.
If this is the study I am thinking of, it used the methodology of
simply assuming that spending by NASA on R&D was as productive as
private industrial R&D. No attempt was made to actually identify the
spinoffs, or judge NASA's contribution to them. The more recent
German study showing that space R&D is less effective at creating
spinoffs than private R&D (as judged by patent citations) would tend
to discredit this.
I don't recall who did the study, but it got mentioned in this
newsgroup some years ago... anyone remember?
Paul F. Dietz
dietz@cs.rochester.edu
------------------------------
Date: Tue, 22 Dec 1992 06:34:06 GMT
From: "Michael V. Kent" <kentm@aix.rpi.edu>
Subject: Justification for the Space Program
Newsgroups: sci.space,talk.politics.space
In article <1992Dec22.023353.10922@magnus.acs.ohio-state.edu> gcoleman@magnus.acs.ohio-state.edu (George Coleman) writes:
>>for every dollar spent in space there is an estimated 7 dollar return in
>> space spin offs.
>Maybe, just maybe private firms have a hard time marketing new advances but
>with a 7/1 return they should be able to find a way.
The 7:1 return doesn't go to the agency which spent the money -- it goes to
society in general. If NASA got a 7:1 return directly, we wouldn't be having
so much trouble funding Space Station Freedom. :)
Mike
--
Michael Kent These views are solely those of the author.
Flight Test Engineer <Looking for Internet access in St. Louis.>
McDonnell Douglas, St. Louis
kentm@pro-applejacks.cts.com Tute-Screwed Aero Apple II Forever !!
------------------------------
Date: 21 Dec 92 21:56:47 GMT
From: Paul Teich <pteich@cayman.amd.com>
Subject: Looking for sci.space archives
Newsgroups: sci.space
I'm looking for sci.space archives which cover the last couple of months;
my news feed only holds a day or two.
Any info appreciated, thanks,
--
Paul R. Teich pteich@cayman.AMD.COM
Advanced Micro Devices, Inc. Direct 1-512-462-4268
5900 E. Ben White Blvd., MS 561 WATS 1-800-538-8450 x54268
Austin, Texas 78741 FAX 1-512-462-4756
===============================================================================
Religion loses its meaning as soon as it's explained.
------------------------------
Date: 22 Dec 92 03:44:34 GMT
From: "David W. Berry" <dwb@netcom.com>
Subject: Making Orbit '93
Newsgroups: sci.space
M M A K K IIIII N N GGGG
MM MM A A K K I NN N G G
M M M M A A KKK I N N N G
M M M AAAAAAA K K I N N N G GGGG
M M A A K K I N NN G G
M M A A K K IIIII N N GGGG
OOOO RRRRR BBBB IIIII TTTTTTT 9999 333
O O R R B B I T 9 9 3 3
O O R R BBBB I T 9 9 33
O O RRRRR B B I T 99999 3
O O R R B B I T 9 3 3
OOOO R R BBBB IIIII T 9999 333
15-18 January 1993 Berkeley Marina Mariott
Martin Luther King 1993 Berkeley, Ca
Making Orbit Conventions is proud to announce Making Orbit '93!
It is a fact that most Americans support the idea of a sound space program
that gets real people out into space to do real work. Yet, how far have we
really come toward making that a reality? What is being done to make that
happen? What are the most promising technologies? Will we really get real
people to space soon? Is there anything individuals can do to help make
space living attainable for everyone? Are rocket launch systems the way to
get there? Or are there other viable launch systems? How much of an
influence does science fiction have on science fact and vice-versa?
These are just a few of the questions we hope to address at Making Orbit
'93, a space oriented hard science and science fiction convention sponsored
by Making Orbit Conventions and Space Access Society. Along with answering
these weighty questions, we also intend to have some fun along the way. A
forum will be provided for many organizations so that information can be
shared and enthusiasm for space can be rekindled. This is your chance to
share ideas with the experts who are forging the path to the stars, and the
science fiction writers who have been furnishing us with dreams.
The convention will begin Friday afternoon with two program tracks. One
will be a segment sponsored by the Lunar Society, featuring space oriented
curriculum ideas and guides for educators. The other will be a mixed track
of lighter programming. Then in the evening we really get down to business
with an opening ceremony, participant reception and cash bar where you can
meet all our speakers. On Saturday and Sunday there will be three
programming tracks all featuring space oriented subjects. Two of those
tracks will be oriented to hard science and space information with a
special emphasis on alternate launch technologies and space policy. A third
will be a lighter "Sex in Space" track. On Monday we expect things to wind
down but there will still be lots to do. To round things out, in addition
to our panels, there will be a dealers' room, art show, and evening
hospitality to allow you to share ideas in a more informal atmosphere.
We welcome any suggestions you have that would make this event more
interesting and fun for you. Please feel free to call us with your ideas
for guests, programs or other features. For further info and memberships
contact Making Orbit, 909 Marina Village Parkway #237, Alameda, CA 94501 or
(408) 321-0154.
All this fun and information will be shared in the wonderful atmosphere of
the Berkeley Marina Marriott. The hotel features two pools (one is adults
only), a large spa, and health club, all set in a peaceful nook right on
the waters of the San Francisco Bay in the Berkeley Marina. And all of this
at the great convention rate of $79 per room. For hotel info and
reservations contact the Berkeley Marina Marriott, 200 Marina Blvd,
Berkeley, CA 94710, (510) 548-7920.
Speakers Already Planning to Attend Include
Max Hunter - Rocket Designer
Jerry Pournelle - SF Writer
Larry Niven - SF Writer
G. Harry Stine - Science/SF Writer
Gary Hudson - Space Entrepreneur
Jordin Kare - Laser Launch
Steve Hoeser - Space Technologist
Jim Ransom - Lunar Society
Tim Kyger - Congressional Advisor
Art Bozlee - Soviet Space Expert
J. P. Del Fevero - Space Economics
William Gaubatz - SSTO
Rick Jurmain - SSTO
------------------------------
Date: Tue, 22 Dec 92 01:17:58 EST
From: John Roberts <roberts@cmr.ncsl.nist.gov>
Subject: misc
-From: wingo%cspara.decnet@Fedex.Msfc.Nasa.Gov
-Subject: Re: Justification for the Space Program
-Date: 21 Dec 92 04:32:00 GMT
-Organization: University of Houston
Just a few random comments, not directly relating to the conclusion of the
original post:
-I know
-what fission is and one of the largest plants of that type are within a few
-miles of my present location. Unfortunately the contractor scum that built
-it for TVA's nuclear program did such a poor job that it took over a billion
-dollars just to straighten out all of the defects (Browns Ferry).
Isn't that the one those idiots set fire to while checking for air leaks
with a candle?
-I agree that
-fission is a nice, relatively safe form of energy production. It is also
-very expensive. Each plant costs somewhere in the 5-8 billion dollar range.
Part of that is bad management and nonstandard designs, and part is from
frivolous lawsuits by misguided "environmental" groups and others delaying
the approval process. The nuclear power industry could be managed much better
than it has been in the US - France is a better example of what's possible.
There is an ongoing effort to improve the safety and standardization of
new fission power reactor designs in the US. Maybe it will come along in time
to save the Eastern forests from destruction by acid rain.
-The answer that a third world person would give you to that is that the
-west does not provide the right type of help. It is ok to feed people
-overseas. It does much to make Westerners feel good about themselves and
-how they are helping the starving masses. What is lacking is teaching those
-people how to help themeselves.
-Give me a fish and I eat for today
-Teach me to fish and I eat for a lifetime
There's at least one charity you can give money to that will finance volunteers
who go to third world countries and teach the people how to generate real
wealth.
-What about copper? Yes yes I know that we can substitute aluminum for copper in
-most cases but aluminum is only 90 as efficient as copper at carrying electricty
-This translates into a 10% decrease in the net efficiency in most of our
-power generating and distribution system. If copper were cheaper (more abundant)
-then we could save billions per year just in this area.
Given the high density and mechanical properties of copper, they might elect
to continue using aluminum for long-distance transport even if the prices
of the metals were the same. Copper-plated conductors might be an option.
-What about stainless steel? This has been commented on here before but I'm
-gonna bring it back up. If the cost of stainless were 1/100 of what it is
-today, we could build bridges with it that would last for centuries rather
-than for decades. Since the last round of this discussion, I have spoke with
-Civil engineers (I am an ASCE (American Society of Civil Engineers) member)
-and they would love to have stainless. The more difficult workability would
-more than be offset by the lower operating costs that such bridges entail.
Why don't you and Gary duke it out over this one, and the rest of us will
wait on the sidelines for the outcome? :-)
-Most
-bridges that are steel, such as the Golden Gate must be constantly painted and
-buffed and treated to stop or slow down corrosion.
I've heard that's literally true for the Golden Gate Bridge - they paint it
from one end to the other, then immediately start over.
-Look around at your dead nuclear power program. Look around.
It's not as dead as it was a few years ago.
-Dennis, University of Alabama in Huntsville
John Roberts
roberts@cmr.ncsl.nist.gov
------------------------------
Date: 21 Dec 92 20:22:06 GMT
From: Ted Frank <thf2@ellis.uchicago.edu>
Subject: STS-48 and "SDI": Oberg vs. Hoagland
Newsgroups: sci.skeptic,sci.astro,sci.space,alt.alien.visitors
In article <1992Dec4.215702.5218@news.cs.brandeis.edu> corbisier@binah.cc.brandeis.edu writes:
>James Oberg will _of course_ have an explanation. He is a member of
>PSICOP and works with Philip Klass, THE well-known skeptic "nothing-
>is-real" other famous member of PSICOP. I've been seeing more and
>more things from Oberg lately, and I *never* see this connection
>mentioned, only his NASA ties.
>
>Robert Sheaffer may be "Skepticus Maximus", but for the rest of us
>with open minds, please consider the source.
>
>Barb
You seem to be so open-minded that you didn't address a single thing
Oberg said. He had a remarkably good track record on the Soviet space
program.
At any rate, it's posts like this that make me want to disassociate
myself from my alma mater. Sheesh.
--
ted frank | thf2@ellis.uchicago.edu
standard disclaimers | void where prohibited
the university of chicago law school, chicago, illinois 60637
------------------------------
Date: 22 Dec 92 06:24:01 GMT
From: Greg Moore <strider@clotho.acm.rpi.edu>
Subject: Terminal Velocity of DCX? (was Re: Shuttle ...)
Newsgroups: sci.space
In article <ewright.724698268@convex.convex.com> ewright@convex.com (Edward V. Wright) writes:
>
>>The average total cost of a shuttle mission is a little over $500 million
>>not a billion+.
>
>Only if you learned math from the "Hitchhiker's Guide."
>
Do you think it is possible for you to reply to a person's posting
without being insulting or condescending?
>Divide the amount of money NASA spends on the Space Shuttle program
>every year by six flights per year.
>
Right, except last year they fley 8 times. This year they
have 7 planned.
------------------------------
Date: 22 Dec 92 06:30:03 GMT
From: "Michael V. Kent" <kentm@aix.rpi.edu>
Subject: Voyager UVS shutdown
Newsgroups: sci.space
In article <1992Dec20.164145.9851@head-cfa.harvard.edu> mcdowell@head-cfa.harvard.edu (Jonathan McDowell) writes:
>You ain't heard nothing yet, Bill. All of the Mission Ops and Data
>Analysis programs (IUE, Einstein, EUVE, GRO, ROSAT, etc) were called
>to D.C. last week for an emergency review and further major cuts. The usual
>Congress smarts - spend half a billion on getting a mission up, then cut
>the one percent of that that would let you do a good job with the
>results. MO&DA is one of the cheapest and most important things NASA
>does but one of the first to get cut.
>
>[Declaration of interest: of course, my salary comes out of this budget,
>so I would say that, wouldn't I.]
My salary doesn't come out of this budget, and I still think it's a stupid
thing to cut.
Mike
--
Michael Kent These views are solely those of the author.
Flight Test Engineer <Looking for Internet access in St. Louis.>
McDonnell Douglas, St. Louis
kentm@pro-applejacks.cts.com Tute-Screwed Aero Apple II Forever !!
------------------------------
From: bill nelson <billn@hpcvaac.cv.hp.com>
Newsgroups: alt.folklore.urban,sci.space
Subject: Re: Mnemonics
Message-Id: <1992Dec22.020707.23411@hpcvaac.cv.hp.com>
Date: 22 Dec 92 02:07:07 GMT
Article-I.D.: hpcvaac.1992Dec22.020707.23411
References: <1992Dec21.224604.22188@mnemosyne.cs.du.edu>
Organization: Hewlett-Packard Company, Corvallis, Oregon USA
Lines: 24
Sender: news@CRABAPPLE.SRV.CS.CMU.EDU
Source-Info: Sender is really isu@VACATION.VENARI.CS.CMU.EDU
jfurr@nyx.cs.du.edu (JKF) writes:
: In article <1992Dec21.211902.4322@hpcvaac.cv.hp.com> billn@hpcvaac.cv.hp.com (bill nelson) writes:
: >: or near miss in about 4 billion years. Working backwards they should also
: >: have collided about 2 billion years ago (c. 1/2 the estimated age of the
: >: solar system). Some people speculate that Pluto is an asteroid that was
: >: captured by Neptune at this time.
: >
: >Yeah - some people do make such a speculation. The same ones who ignore the
: >fact that Pluto has a moon. Also, the same people ignore the fact that none
: >of the asteroids travel anywhere close to that far out. They are pretty much
: >confined between the orbits of Jupiter and Mars.
:
: Sorry, Bill, but there are many planetoids and asteroids that orbit beyond
: the orbit of Jupiter. One such is a minor planet called Chiron. There
: are quite a few others as well.
Note that I said "pretty much".
There certainly are some that travel outside the orbit of Jupiter - as well
as inside the orbit of the Earth. However, I know of none that travel outside
the orbit of Saturn, much less any of the planets further out.
Bill
------------------------------
End of Space Digest Volume 15 : Issue 582
------------------------------