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Date: Fri, 26 Mar 93 05:57:08
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V16 #371
To: Space Digest Readers
Precedence: bulk
Space Digest Fri, 26 Mar 93 Volume 16 : Issue 371
Today's Topics:
Alumnium was available in Elizabethan times?
Clueless Wardisms (was Re: UARS status?)
Craf's penetrator
Galileo Update - 03/25/93
gravity
Gravity waves, was: Predicting gravity wave quantization & Cosmic Noise (2 msgs)
How to cool Venus
Idle Question
Luddites in space
mars coordinates
Plans, absence therof
Predicting gravity wave quantization & Cosmic Noise
Rocket clones: reduce risk of introducing new tech
SSTO: A Spaceship for the rest of us
Stockman, Mark, and Keyworth (was Re: Flight time comparison...) (2 msgs)
Welcome to the Space Digest!! Please send your messages to
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(THENET), or space-REQUEST@isu.isunet.edu (Internet).
----------------------------------------------------------------------
Date: Thu, 25 Mar 1993 21:27:01 GMT
From: fred j mccall 575-3539 <mccall@mksol.dseg.ti.com>
Subject: Alumnium was available in Elizabethan times?
Newsgroups: sci.space,sci.materials
In <C4Ez9J.GKE@news.cso.uiuc.edu> gambit@uxa.cso.uiuc.edu () writes:
>In article <1on5ljINNm55@gap.caltech.edu> palmer@cco.caltech.edu (David M. Palmer) writes:
>>cam@hawk.adied.oz.au (The Master) writes:
>>>Funny how at the time it would have cost an enormous amount of money
>>>and now it's so cheap. It's almost like thinking of people drinking
>>>out of gold Coke cans in the future :)
>>
>>Gold isn't very useful for Coke cans (not strong enough), but diamond
>>will be used for all sorts of things, once nanotech comes in.
> ^^^^^^^^
>Has anyone ever defined this term?
Yes. I can't recall the title of the book, though. It basically
refers to what amounts to miracles of engineering on the near-atomic
scale. For example, insulin factories the size of bacteria (but
mechanical, not organic), self-replicating robots (once again bacteria
sized), etc. Proponents proclaim it as if it is the Second Coming and
nano-technology will be the solution to all problems.
>I seem to be hearing it an awful lot
>lately. (By the way, am I right in thinking that this came from Maxis'
>"SimEarth" game?)
No. You have causality running backwards.
--
"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: 25 Mar 93 13:29:36 -0600
From: Bill Higgins-- Beam Jockey <higgins@fnalf.fnal.gov>
Subject: Clueless Wardisms (was Re: UARS status?)
Newsgroups: sci.space
In article <24MAR199317112710@stdvax>, abdkw@stdvax (David Ward) writes:
> I believe so...GSFC's Director's Weekly's haven't reported any
^^^^^^ ^^^^^^^^^^ ^^^^^^^^
> catastrophic failures since the prime solar array problems last
> summer. As a matter of fact, I believe I read that UARS was the
> first satellite to have mapped the Mt. Pinatubo cloud.
Is this publication available on-line? Any chance we could arrange to have it
posted to sci.space.news?
> BTW, thanks for your interest. I was beginning to think that
> Goddard wasn't a place where we built things that went into space.
> It's good to hear that someone remembers that we do work here (and
> have successes and failures like the rest of you).
Agreed.
> Also, thanks for the last two week's conversation. As a new poster,
> I can't wait to see the subjest "Clueless Wardisms"
Wait your turn, punk. There are lots of old-timers who haven't been
honored with "Clueless Spencerisms" or "Clueless Higginsisms" yet.
Bill Higgins, Beam Jockey | According to the doctrine
Fermi National Accelerator Laboratory | of natural selection,
Bitnet: HIGGINS@FNAL.BITNET | *you* were designed
Internet: HIGGINS@FNAL.FNAL.GOV | by a committee.
SPAN/Hepnet: 43011::HIGGINS | The biggest committee ever.
------------------------------
Date: Thu, 25 Mar 1993 21:09:32 GMT
From: fred j mccall 575-3539 <mccall@mksol.dseg.ti.com>
Subject: Craf's penetrator
Newsgroups: sci.space
In <C4DBCH.30s.1@cs.cmu.edu> 18084TM@msu.edu (Tom) writes:
>Henry Spencer:
>>>I'd also note that CRAF was attempting to "stay within budget" by shedding
>>>pieces as the overruns mounted. For example, the penetrator got dropped
>>>from the mission to save money.
>Bill Higgins:
>>Therefore the penetrator *didn't* get dropped from the mission?
>Maybe it's stuck for the same reason as the Galielo HGA. Oh, well,
>at least they have another one they can drop at the next encounter :-)
>Seriously, Bill, do you mean, since they overran the budget, they must
>have kept the penetrators instead of cutting costs? Or do you mean they
>didn't drop the penetrators, alone, since the whole thing got dropped?
>Or what?
I suspect Bill meant it as a joke via a play on words, Tommy. The
penetrator didn't get dropped (onto the target) from the mission (the
actual mission) because it wasn't present on the spacecraft (because
it had been dropped from the mission).
[Or maybe my mind just works in convoluted ways.]
--
"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: 26 Mar 1993 00:32 UT
From: Ron Baalke <baalke@kelvin.jpl.nasa.gov>
Subject: Galileo Update - 03/25/93
Newsgroups: sci.space,sci.astro,alt.sci.planetary
Forwarded from Neal Ausman, Galileo Mission Director
GALILEO
MISSION DIRECTOR STATUS REPORT
POST-LAUNCH
March 19 - 25, 1993
SPACECRAFT
1. On March 22 and March 24, a NO-OP command was sent to reset the command
loss timer to 240 hours, its planned value during this mission phase.
2. On March 22, the joint gravity wave experiment with Mars Observer (MO)
and Ulysses (ULS) began. The experiment is scheduled to continue throughout
the EE-12 (Earth-Earth #12) sequence and complete on April 12, 1993.
3. On March 24, a periodic RPM (Retro-Propulsion Module) 10-Newton thruster
maintenance activity was performed; all 12 thrusters were flushed during the
activity. Thruster performance throughout the activity was nominal.
4. On March 24 real-time commands were sent to switch from 40 bps uncoded
telemetry to 40 bps coded telemetry. These commands were sent to improve the
data quality of the downlink telemetry.
5. On March 25, cruise science Memory Readouts (MROs) were performed for the
Extreme Ultraviolet Spectrometer (EUV), Dust Detector (DDS), and Magnetometer
(MAG) instruments. Preliminary analysis indicates the data was received
properly.
6. On March 25, real-time commands were sent to update the Command and Data
Subsystem (CDS) flight software. Specifically, the change allows the memory
readout command to perform consecutive memory readouts at 10 bps. The change
modified the number of minor frames each block of data is collected when a
memory readout command is issued.
7. The AC/DC bus imbalance measurements have not exhibited significant change
(greater than 25 DN) throughout this period. The AC measurement reads 19 DN
(4.3 volts). The DC measurement reads 148 DN (17.4 volts). These
measurements are consistent with the model developed by the AC/DC special
anomaly team.
8. The Spacecraft status as of March 25, 1993, is as follows:
a) System Power Margin - 69 watts
b) Spin Configuration - Dual-Spin
c) Spin Rate/Sensor - 3.15rpm/Star Scanner
d) Spacecraft Attitude is approximately 10 degrees
off-sun (lagging) and 8 degrees off-earth (leading)
e) Downlink telemetry rate/antenna- 40bps(coded)/LGA-1
f) General Thermal Control - all temperatures within
acceptable range
g) RPM Tank Pressures - all within acceptable range
h) Orbiter Science- Instruments powered on are the PWS,
EUV, UVS, EPD, MAG, HIC, and DDS
i) Probe/RRH - powered off, temperatures within
acceptable range
j) CMD Loss Timer Setting - 240 hours
Time To Initiation - 234 hours
UPLINK GENERATION/COMMAND REVIEW AND APPROVAL:
1. The EJ-1 (Earth-Jupiter #1) preliminary sequence and command generation
package was approved by the Project on March 19, 1993. This sequence covers
spacecraft activity from April 12, 1993 to June 14, 1993 and includes the
Radio Relay Antenna (RRA) slew test on April 28, 1993.
TRAJECTORY
As of noon Thursday, March 25, 1993, the Galileo Spacecraft trajectory
status was as follows:
Distance from Earth 107,167,000 km (0.72 AU)
Distance from Sun 248,844,400 km (1.66 AU)
Heliocentric Speed 100,700 km per hour
Distance from Jupiter 581,121,600 km
Round Trip Light Time 12 minutes, 0 seconds
SPECIAL TOPIC
1. As of March 25, 1993, a total of 67692 real-time commands have been
transmitted to Galileo since Launch. Of these, 62585 were initiated in the
sequence design process and 5107 initiated in the real-time command process.
In the past week, 58 real time commands were transmitted: 57 were initiated
in the sequence design process and one initiated in the real time command
process. Major command activities included commands to reset the command
loss timer, switch to 40 bps coded telemetry and update the CDS flight
software.
___ _____ ___
/_ /| /____/ \ /_ /| Ron Baalke | baalke@kelvin.jpl.nasa.gov
| | | | __ \ /| | | | Jet Propulsion Lab |
___| | | | |__) |/ | | |__ M/S 525-3684 Telos | Don't ever take a fence
/___| | | | ___/ | |/__ /| Pasadena, CA 91109 | down until you know the
|_____|/ |_|/ |_____|/ | reason it was put up.
------------------------------
Date: Thu, 25 Mar 1993 18:30:50 GMT
From: fred j mccall 575-3539 <mccall@mksol.dseg.ti.com>
Subject: gravity
Newsgroups: sci.space
In <1993Mar23.160414.2239@sed.stel.com> bobc@sed.stel.com (Bob Combs) writes:
>In article cf549@cleveland.Freenet.Edu (Jim Baker) writes:
>>
>>Acknowledging the fact that the earth has enough gravity
>>to hold an atmosphere in place, and the moon (with about 1/6
>>of earth's gravity) does not, how much gravitiy does it take
>>to hold an atmosphere? This is realizing it depends on the
>>type of atmosphere, but I am looking for a general answer.
>>
>>Jim Baker <jlbaker@tenet.edu>
>Isn't the presence of an atmosphere a function of
>chemistry and chemical reactions, vice gravity?
Original creation, yes (at least in part). However, to retain any
atmosphere for any appreciable amount of time (geologically speaking),
the escape velocity must be high enough so that the RMS velocity of
the gas in the atmosphere is comfortably below it. Otherwise, your
atmosphere escapes to space and is gone.
Note that this is why there is a paucity of light gasses in the
Earth's atmosphere; the RMS velocities of the lighter molecules are
simply too high at the atmospheric temperature of earth to be retained
for very long.
--
"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: 25 Mar 93 20:19:49 GMT
From: "Thomas E. Smith" <tes@motif.jsc.nasa.gov>
Subject: Gravity waves, was: Predicting gravity wave quantization & Cosmic Noise
Newsgroups: sci.space,sci.astro,sci.physics,alt.sci.planetary
sichase@csa3.lbl.gov (SCOTT I CHASE) writes:
>In article <1993Mar25.140107.7414@aio.jsc.nasa.gov>, tes@motif.jsc.nasa.gov. (Thomas E. Smith) writes...
>>crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass) writes:
>>>In article <1993Mar25.014429.10077@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman)
>writes:
>>>>in terminology and conditions here. A gravity wave can be viewed, like
>>>>a sound wave, as a compression wave in spacetime. It alternately compresses
>>>>and stretches the fabric of space (hackneyed term) like a steel ball
>>
>>I don't think that it ever compresses space, only stretches.
>
>Not only does it compress space, but it does so at the same time as it
>stretches it in the perpendicular direction. Gravity waves have spin 2,
>which means that they produce quadrapole deformations of space. In
>one direction they stretch, and in the other direction they compress.
Well, yes, that is true. But isn't the net effect that it lengthens the
distance from point A to point B thru curved space? It still stretches space,
though it has to do it in another dimension.
------------------------------------------------------------------------------
| Living on Earth may be expensive,|Tom E. Smith | ._________ |
| but it includes an annual free |tes@gothamcity.jsc.nasa.gov| |= (0_, \ \ |
| trip around the Sun. | | |= |0 ` / | |
|--------------------------------------------------------------| |---u----/ |
| And no, I don't speak for my company or any other company. | |
------------------------------------------------------------------------------
------------------------------
Date: 25 Mar 1993 14:44 PST
From: SCOTT I CHASE <sichase@csa1.lbl.gov>
Subject: Gravity waves, was: Predicting gravity wave quantization & Cosmic Noise
Newsgroups: sci.space,sci.astro,sci.physics,alt.sci.planetary
In article <1993Mar25.201949.2739@aio.jsc.nasa.gov>, tes@motif.jsc.nasa.gov. (Thomas E. Smith) writes...
>sichase@csa3.lbl.gov (SCOTT I CHASE) writes:
>>In article <1993Mar25.140107.7414@aio.jsc.nasa.gov>, tes@motif.jsc.nasa.gov. (Thomas E. Smith) writes...
>>>I don't think that it ever compresses space, only stretches.
>>
>>Not only does it compress space, but it does so at the same time as it
>>stretches it in the perpendicular direction. Gravity waves have spin 2,
>>which means that they produce quadrapole deformations of space. In
>>one direction they stretch, and in the other direction they compress.
>
>Well, yes, that is true. But isn't the net effect that it lengthens the
>distance from point A to point B thru curved space? It still stretches space,
>though it has to do it in another dimension.
There is no other dimension. The manifold of spacetime is still
four-dimensional, it's just changing shape a little as the wave goes by.
Curved spacetime is not embedded within some other flat space. It just "is".
Maybe someone else can explain this better.
-Scott
--------------------
Scott I. Chase "It is not a simple life to be a single cell,
SICHASE@CSA2.LBL.GOV although I have no right to say so, having
been a single cell so long ago myself that I
have no memory at all of that stage of my
life." - Lewis Thomas
------------------------------
Date: Thu, 25 Mar 1993 19:57:28 GMT
From: Paul Dietz <dietz@cs.rochester.edu>
Subject: How to cool Venus
Newsgroups: sci.space
In article <1993Mar25.135610.13998@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes:
>> Actually, the history of the development of thermonuclear weapons
>> is that big ones were developed first. The first one, a bulky
>> device using liquid deuterium/tritium, achieved 10 MT; the first
...
> Well big computers came first too. I think that's mostly a matter
> of technical prowess and not fundamental limitations.
Note that the "big computers" they used -- remember, this is 1951 --
were less powerful than today's palmtop machines. The fact that such
primitive machines were sufficient says something about the
level of sophistication required.
> I don't think I understand any of this. Laser fusion is supposed to
> work by heating the target via compression. The two effects are
> completely intertwined. I don't see how you're going to heat the
> material without compressing it. What's to prevent an isothermal
> expansion if the target material isn't constrained by compression?
I suggest you consult "The Basic Physics of Laser Fusion" (R. G.
Evans, Can. J. Phys., 64(8), August 1986, pages 893-899.)
Heating in laser fusion is mostly "bootstrap" heating, from alpha
particles deposited as a burn wave propagates through the compressed
pellet (the "spark" at the center is heated by compression). The
nuclei don't care where their kinetic energy came from, of course.
One could heat bulk deuterium by (for example) direct illumination
with thermal x-rays from a driver.
What prevents expansion? Nothing (although one could tamp the plasma
to impede the expansion and reduce the escape of thermal radiation).
Expansion takes a nonzero time due to (1) the finite speed of sound in
the plasma, and (2) the nonzero linear dimensions of the plasma.
Roughly speaking, the expansion time is the product of these two
values. Speed of sound in an ideal gas is independent of density, so
the expansion time is proportional to (2). This means we can make the
expansion take as long as we want by making the system bigger. This
does increase the energy input needed to bring the system up to fusion
temperature.
For D-T fusion, nonnegligible fusion yields requires that the product
of the density and pellet radius be at least 4.2 g cm^-2. For D-T at
normal density (about .2 g/cc), this yields a pellet radius of 21 cm,
and a yield of about 1 megaton. Acceptable yield in smaller pellets
can only be achieved by compression. Conversely, the rho R product is
larger for bigger spheres of DT liquid, making the reaction go more
nearly to completion. Deuterium by itself is somewhat less reactive,
but for large enough R the same principle applies.
> My understanding of nuclear explosives is that the fundamental
> problem is to prevent the device from dissassembling before
> sufficient captures occur.
Yes. Making the device larger *helps*, because disassembly takes
longer (but you need a bigger driver). For big enough bombs,
the reaction is essentially complete before the plasma can
significantly expand.
Paul F. Dietz
dietz@cs.rochester.edu
------------------------------
Date: Thu, 25 Mar 1993 19:27:55 GMT
From: zellner@stsci.edu
Subject: Idle Question
Newsgroups: sci.space
In article <C4G4Lu.115.1@cs.cmu.edu>, flb@flb.optiplan.fi ("F.Baube[tm]")
writes:
> Just how much *would* it cost to get my very own Scout launch ?
>
> How much weight would I get to lob into LEO ?
>
I have heard numbers like $10 to $12 million for 500 pounds into LEO.
Ben
------------------------------
Date: Thu, 25 Mar 1993 20:49:04 GMT
From: fred j mccall 575-3539 <mccall@mksol.dseg.ti.com>
Subject: Luddites in space
Newsgroups: sci.space,talk.politics.space
In <C4C6Ep.GIA@techbook.com> szabo@techbook.com (Nick Szabo) writes:
>Luddites, 1811: bands of hand-weavers and sympathizers who went around
>destroying automated textile machinery, insisting that what people
>really want are hand-crafted works, and they don't care how warm it
>keeps them at night, or whether they can afford it. Ignoring economics
>at every turn, they argued that machines "can't replace human skill", and
>insisted on subsidies of the old technology, and/or slowing down the new
>technology to redress their greivances. The judgement of history is
>that they were a bunch of whining idiots.
>Luddites, 1993: bands of astronaut and their groupies who go around
>calling automated spacecraft "toasters", "black box brownies",
>etc., who insist that the vast bulk of NASA funds should be devoted
>to their projects while Halley flyby, CRAF, etc. are cancelled and
>other planetary projects are grossly misdesigned to fit on astronaut
>carrying launchers, or are delayed. Luddites rail against the alleged
>"failures of AI" while Japan's car makers kick our butts by installing
>robots, insist that what people "really" want is to see their beloved
>astronauts in space, and don't car how useful it is or whether they
>can afford it. Ignoring economics at every turn, they insist on massive
>government subsidies for their bizarrely expensive, obsolete technologies
>to redress their greivances.
You know, Nick, you are really an idiot. Sorry, but somebody had to
say it.
Have you ever seen me (or anyone else here, for that matter, no matter
how 'pro-man in space' they are) do anything like "insist that the
vast bulk of NASA funds should be devoted to [my] products while
Halley flyby, CRAF, etc. are cancelled and other planetary projects
are gorssly misdesigned to fit on astronaut carrying launchers or are
delayed"? The only folks I've ever seen insist that funds should be
taken from other peoples' programs and spent on the ones they favor
are those of your ilk, who apparently don't think they can justify
their own funds without trashing everyone else first.
Have you ever seen me (or anyone else here, for that matter, no matter
how 'pro-man in space' they are) do anything like "rail against the
'failures of AI'"?
I hardly ever 'ignore economics', since I went to the trouble and
effort to get a degree in the subject so I would understand things
that to you are apparently beyond comprehension. Perhaps you should
learn something real about the subject instead of just running your
flaming mouth, bucko?
If I thought you were typical of the proponents of planetary science I
would adopt your tactics and trash what you want. However, that's
hardly the way anyone with any sense would use to try to convince
anyone to fund their programs at a higher level. I guess that tells
you what I think of you and your way of thinking.
>Hopefully with Truly ad nauseum out of there, the worst of the
>Luddite destruction of NASA is over.
Has it *EVER* occurred to you to try to justify the things you think
are good ideas without trying to trash everything else in the process?
That just shows how intellectually bankrupt you yourself must think
your position is, since you obviously don't think it can compete for
funds based on its own merits.
--
"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: 26 Mar 93 02:12:56 GMT
From: Steve Collins <collins@well.sf.ca.us>
Subject: mars coordinates
Newsgroups: sci.space
I heard recently that there have been several "official" prime meri{dians
for mars{. Does anyone know if this is true and if so, whether the
prime meridian (or pole) has moved a long ways from the current
(IAU ?) location?
Steve Collins
------------------------------
Date: Thu, 25 Mar 1993 23:14:21 GMT
From: "Charles J. Divine" <xrcjd@resolve.gsfc.nasa.gov>
Subject: Plans, absence therof
Newsgroups: sci.space
In article <C4DBA0.2w6.1@cs.cmu.edu> 18084TM@msu.edu (Tom) writes:
>D Mohoney
>Wingo isn't an indentured slave to the U.S. govenment. He has the right to say
>>what he wants as a citizen of his country.
>
>You are ignoring a conflict of interest, though. Since Wingo works for the
>people that collect my money, his voice will carry further than mine.
Have you any proof of this statement? I've worked in the private
sector, for government as a goverment employee and as a contractor.
It's been my perception that independent citizens have just as much,
if not more, say in government policy as do low level employees and
contractors.
>Since
>it's my money, I should have a greater say. Since Dennis usually advocates
>greater powers for the taxing authorities, he is also abusing his position,
>since he is an agent for the taxing authorities.
How do you figure this? It seems to me you are using the term "agent"
too broadly.
>
>He has a right to say what he wants, as a citizen. He does not have a
>right to say what he wants, as a gov agent.
And just when is he doing these different things? What criteria are
you using?
--
Chuck Divine
------------------------------
Date: Thu, 25 Mar 1993 21:00:17 GMT
From: Cameron Randale Bass <crb7q@kelvin.seas.Virginia.EDU>
Subject: Predicting gravity wave quantization & Cosmic Noise
Newsgroups: sci.space,sci.astro,sci.physics,alt.sci.planetary
In article <1993Mar23.221248.2618@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes:
>In article <C4BJ37.KuL@murdoch.acc.Virginia.EDU> crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass) writes:
>> So you increase the wavelength and decrease the frequency.
>> It would also seem to me that in such a situations clocks run slow
>> 'within' the gravitational disturbance. The two disturbances
>> (gravitational and electromagnetic) fly back to the detector,
>> and the gravitational disturbance slows the 'clocks' at
>> the receiver to effectively increase the frequency
>> and cancel the effect.
>
>If we assume that the gravitational wave is a classical wavefront,
>and we assume it travels at lightspeed, then your objection only
>occurs when the Earth, satellite, and source of gravity waves are
>all lined up. If the gravitational disturbance is arriving from
>some angle off that line, the EM wave and the gravity wave will
>only be coincident at one point along the line of sight.
Yes, I know. My original question was predicated on
this occurring, he said for the second time (humourous thingy).
However, it would not seem to be a 'pointlike' thing
exactly since the 'gravitational wavelength' is
substantial. If are able to calculate it as for electromagnetic
waves it is somewhere between 10^7 km and about 3 x 10^10 km.
dale bass
------------------------------
Date: 25 Mar 93 14:07:55 GMT
From: Pat <prb@access.digex.com>
Subject: Rocket clones: reduce risk of introducing new tech
Newsgroups: sci.space
I don't know about scout production rates, but during the 1987
shut down of just about everything, NASA dragged a scout out of
the NASM dusted it off and flew it at white sands.
Production has to have been tight, if they had to scrunge
off the smithsonian.
pat
------------------------------
Date: 25 Mar 93 14:15:05 GMT
From: Pat <prb@access.digex.com>
Subject: SSTO: A Spaceship for the rest of us
Newsgroups: sci.space
Henry did an article on the technical aspects of the
DC-X,Y,1 which was re-posted recently. I reccomended that
it be placed in the FAQ.
The basic trick behind dropping costs for the DC- Clipper
series, is that they threw out Rocket Safety margins
in favor of Airliner Safety Margins.
Structural limits are 140% of expected loads, not 105% of loads.
Engines will run at 65% of Red-Line, not like the shuttle
while is 97%. The engines are rated to run for
several hours, with multiple re-starts.
Electronics modules are LRU's not integrated to the structure,
so that airline mechnaics can fix most any non-structural problem.
The DC will need refurbishment, but every 100 or 1,000 hours, like
a 747, rather then at every flight, like a rocket or the shuttle.
pat
------------------------------
Date: Thu, 25 Mar 1993 21:25:42 GMT
From: Dave Michelson <davem@ee.ubc.ca>
Subject: Stockman, Mark, and Keyworth (was Re: Flight time comparison...)
Newsgroups: sci.space
In article <1993Mar25.174100.19966@den.mmc.com> seale@possum.den.mmc.com (Eric H Seale) writes:
>>
>>George Keyworth, Reagan's science advisor, was apparently a good friend
>>to Science in general but lacked the influence enjoyed by either his
>>predecessors or his colleagues.
>
>I guess I haven't used those particular neurons in a while... :-) I
>could have sworn I remembered some off-the-cuff remark by Keyworth (in
>his earlier days) to the effect that space exploration was a "waste" of
>funds "better" spent on SDIO (grrrr...). Musta' been Stockman. I'll
>have to pick up the book so I can recover that part of my brain.
There is no doubt that Keyworth was a big fan of SDIO, but he was also
a strong promoter of the Hubble Space Telescope and Shuttle-based astronomy
(like the Astro mission flown last year). Privately, he wasn't a big fan of
JPL but then he was from LANL :-) Notice that I only said he was "a good
friend to Science in general".
The real bad guys were David Stockman (the man with the Black Book) and
Hans Mark (the man with the Blue Hat).
---
Dave Michelson University of British Columbia
davem@ee.ubc.ca Antenna Laboratory
------------------------------
Date: Thu, 25 Mar 1993 23:50:08 GMT
From: Dave Michelson <davem@ee.ubc.ca>
Subject: Stockman, Mark, and Keyworth (was Re: Flight time comparison...)
Newsgroups: sci.space
In article <neff.62.733098193@iaiowa.physics.uiowa.edu> neff@iaiowa.physics.uiowa.edu (John S. Neff) writes:
>>
>>There is no doubt that Keyworth was a big fan of SDIO, but he was also
>>a strong promoter of the Hubble Space Telescope and Shuttle-based astronomy
>
>In the book "The Power Game" by Kedrick Smith he tells how SDIO came about.
>According to McFarlane and Keyworth and others, Pres. Reagan wanted
>to prevent leaks and had the staff of the National Secruity Council
>do the draft the SDI speech. Keyworth was brought into the loop by McFarlane
>to provide scientific support. Keyworth felt at that stage all he could
>do was engage in damage control. I realize that this could be just
>self serving BS on the part of Keyworth, but I don't think it was because
>of his subsequent actions and speeches.
>
Many people "on the inside" saw SDIO as an opportunity to develop useful
technologies under the guise of developing a space-based defense system.
How else could the governmemt of the day be persuaded to fund the develop-
ment of exotic things like free electron lasers, advanced computer systems,
and SSTO's? I'm not saying that *no one* believed that SDI would work.
But I am suggesting that more than a few people bit their lip and took
advantage of the opportunity to further their own pet interests with, I'm
sure, the best of intentions. It's not the first time technical people
have jumped on such a bandwagon (von Braun did so at Peenemunde) and not
the last, either.
---
Dave Michelson University of British Columbia
davem@ee.ubc.ca Antenna Laboratory
------------------------------
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From: Pat <prb@access.digex.com>
Newsgroups: sci.space
Subject: Re: Plans and Clueless -isms
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In article <C4EKrw.IyC@brunel.ac.uk> mt90dac@brunel.ac.uk (Del Cotter) writes:
>In article <1ol3mk$cp1@access.digex.com> prb@access.digex.com (Pat) writes:
>
>> If aluminum was noted during roman times,
>
>It wasn't. There is one claim of a mysterious metal, the producer of
>which said he got from clay.
>
Note the IF.
>>then it indicates it needed even less of a technology base to extract
>>then I guessed.
>
>You guessed wrong. There is no elizabethan (I) aluminium in the Tower
>of London.
>
Hey, I cited my source. Granted a high school teacher is not a reference
document, but I'll have to do some serious research.
>>I guess Bronze age technologies could reach it.
>
>Ouch! You have no idea how impossible this is. Al is hellishly
>difficult to extract from its oxides.
>
>>Probably the Indians or Arabs also had identified aluminum.
>
>No, no, no!
>
Anything wrong with a little speculation?
>
>My point was, when bashing someone elses grasp of history, it's a good
>idea to check your own facts.
>
Hey, I made it quite clear, that I was speculating. now as to the
elizabethan part. I guess my source was wrong. I am sorry Del,
but I don't have the energy to go out and research every item.
I don't work at a university and have to travel if i want to access
a large document cache.
pat
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End of Space Digest Volume 16 : Issue 371
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