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1993-07-13
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Date: Fri, 26 Mar 93 05:33:41
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V16 #369
To: Space Digest Readers
Precedence: bulk
Space Digest Fri, 26 Mar 93 Volume 16 : Issue 369
Today's Topics:
Can we still build the Saturn V?
Flame Derby (was Re: Luddites in space)
Flight time comparison: Voyager vs. Gallileo (2 msgs)
Idle Question
Low cost tele-operations & marsrover
NASA and Congress
Orbital Skysurfing Club/DTO...
Predicting gravity wave quantization & Cosmic Noise (3 msgs)
Robots, BASE, help..
Rocket clones: reduce risk of introducing new tech
Russia's OPERATIONAL Starwars Defense System
SDIO VS NASA (was Re: Retraining at NASA)
Space Posters, and where to get them?
temperature of Lunar soil
the call to space (was Re: Clueless Szaboisms )
Time Machine!?
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: 25 Mar 93 18:40:22 GMT
From: fred j mccall 575-3539 <mccall@mksol.dseg.ti.com>
Subject: Can we still build the Saturn V?
Newsgroups: sci.space
In <2306@epochsys.UUCP> jcook@epoch.com (Jim Cook) writes:
>In article 2928@iti.org, aws@iti.org (Allen W. Sherzer) writes:
>>The House Science Committee Space Subcommittee had hearings on
>>this subject about 2 years ago. There is enough data available to
>>start Saturn production again.
>>
>>However, it would cost $16 billion to begin production again and
>...
>$16 BILLION? Not $16 million?
$16 million isn't enough to do *anything*. You probably couldn't even
have a group QC all the plans and make sure everything is ok for that
amount of money. Remember, we're talking about having to set up
entire suites of tooling. This won't come cheap.
--
"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 18:48:43 GMT
From: fred j mccall 575-3539 <mccall@mksol.dseg.ti.com>
Subject: Flame Derby (was Re: Luddites in space)
Newsgroups: sci.space,talk.politics.space
In <1or2vi$2rs@access.digex.com> prb@access.digex.com (Pat) writes:
>In article <STEINLY.93Mar24125701@topaz.ucsc.edu> steinly@topaz.ucsc.edu (Steinn Sigurdsson) writes:
>|In article <1993Mar24.091928.1@fnalf.fnal.gov> higgins@fnalf.fnal.gov (Bill Higgins-- Beam Jockey) writes:
>|
>| In article <1op22q$5qf@agate.berkeley.edu>, gwh@soda.berkeley.edu (George William Herbert) writes:
>| > Nick: hold your breath for a minute and don't post anything tomorrow.
>|
>| > Dennis: hold your breath for a minute and don't post anything tomorrow.
>|
>| > You two are both smart enough not to have to get into flame wars every
>| > few months...
>|
>| Maybe they should both take a break and gang up on Allen.
>|
>| What do you think, George, are pat and Steinn promising new contenders
>| in the Flame Derby?
>|
>|Eek, and here I've been holding my breath for a whole day now!
>|Definitely time to stop - no point anyway, I can never equal the
>|ideological purity of previous champions ;-)
>|
>|
>I'll have to agree with Stein. Neither of us even vaguely come
>close to Dennis or Nick, although, I may be close to fred :-)
No, Pat; you're clearly in the lead. I generally only flame back; you
seem to be self-starting.
--
"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: Thu, 25 Mar 1993 09:53:56 GMT
From: Dave Michelson <davem@ee.ubc.ca>
Subject: Flight time comparison: Voyager vs. Gallileo
Newsgroups: sci.space
In article <824@rins.ryukoku.ac.jp> will@rins.ryukoku.ac.jp (William Reiken) writes:
>>
>> A dearth of funding for planetary science didn't help much either. As I
>> recall, Reagan's "Science Advisor" recommended cancelling ALL funding
>>
>
> Can you please give a name for this quy.
According to the account given by Bruce Murray in "Journey into Space", the
man with the black hat (and the secret "Black Book") was Reagan's budget
director, David Stockman.
Apparently Stockman's "hit list" included the American part of the Inter-
national Solar Polar Mission (the European part was later named Ulysses),
the Venus Orbiting Imaging Radar (scaled back to the Venus Radar Mapper,
later named Magellan), Shuttle-Centaur (which wasn't finally cancelled
until after the 51L accident) and, by September 1981, NASA's entire
solar system exploration program. Only deft maneuvering saved Galileo
and, ultimately, JPL. Only the Shuttle was off limits to Stockman's axe
because of its importance to National Security.
"Journey into Space" is an interesting account by one individual. There
aren't any equations in it, so it's a very quick read. :-)
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.
---
Dave Michelson University of British Columbia
davem@ee.ubc.ca Antenna Laboratory
------------------------------
Date: Thu, 25 Mar 1993 14:35:44 GMT
From: Dan Vento <vento@mars.lerc.nasa.gov>
Subject: Flight time comparison: Voyager vs. Gallileo
Newsgroups: sci.space
In article <1993Mar18.000618.1023@ke4zv.uucp>, gary@ke4zv.uucp (Gary
Coffman) wrote:
>
> In article <1o822uINNf90@elroy.jpl.nasa.gov> tjt@scn1.Jpl.Nasa.Gov writes:
> >the moment, I don't think the U.S. has anything that will launch anything of
> >Voyager size from earth.
>
> Voyagers went up on Titan-Centaurs.
>
The current Titan IV-Centaur could probably handle a Voyager type (1800
Lbs) spacecraft. It really depnds upon where you want to go and on how fast
you want to get there.
Dan Vento
vento@mars.lerc.nasa.gov
NASA Lewis Research Center
Launch Vehicles Project Office
------------------------------
Date: 25 Mar 93 17:27:56 GMT
From: Henry Spencer <henry@zoo.toronto.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 ?
Hard to say. It's not clear that you can; the few remaining Scouts belong
to some combination of NASA, the USAF, and SDIO, and are fully committed.
LTV does not seem to have made a serious attempt to go for the commercial
market, and in particular has not re-opened the production line.
A fair guess would be prices similar to Pegasus, maybe $12M or so.
>How much weight would I get to lob into LEO ?
My copy of the Scout user manual is at home, but typically it's a few
hundred pounds, as I recall.
--
All work is one man's work. | Henry Spencer @ U of Toronto Zoology
- Kipling | henry@zoo.toronto.edu utzoo!henry
------------------------------
Date: 25 Mar 1993 13:34:54 GMT
From: Diaspar Virtual Reality Network <diaspar@nic.cerf.net>
Subject: Low cost tele-operations & marsrover
Newsgroups: sci.space
000222|David42 |032593|010643|Diaspar|*Announcements
*** Diaspar Explores Mars - Sort Of <grin> ***
McDonnell Douglas invited Diaspar to make a presentation Tuesday on using the
Lunar Tele-operation Model techniques for upcoming tests of the joint
NASA/Russian Space Program Mars rover tests this fall.
The presentation was made with interesting results. See Diaspar/News for
details.
000102|David42 |032593|012556|Diaspar|News
On Tuesday, March 23, 1993, McDonnell Douglas asked the Diaspar Virtual Reality
Network to make a presentation on using their tele-operation techniques planned
for the upcoming Lunar Tele-operations Model 1 during tests of the Mars rover
coming up later this year. (LTM1 to be formally announced soon.)
David "42" Mitchell of Diaspar provided demonstrations of tele-operations at
low cost using a radio controlled race car with attached camera. Using both a
VRontier head mounted display and a Virtual Research _Flight Helmet_, Russian
and NASA scientists, together with various McDonnell Douglas researchers, took
turns at operating the vehicle. By using the head mounted displays, the tele-
drivers had the sensation of actually being 3 inches off the ground and gained
experience in handling vehicles using this combination of technologies.
These tests were done in new joint Russian/American facilities being prepared
by McDonnell Douglas. While the driving experiments were conducted outside
in the parking lot, the demonstration continued indoors where scientists and
researchers experienced a tour to other universes created by various artists
and replayed using the head mounted displays.
The entire demonstration covered distances from 3 inches above the ground all
the way to galaxies beyond our own.
This was not a demonstration of full virtual reality since head-tracking,
gloves and other interactive tools were not employed.
However, it was a powerful demonstration of the practicality of low cost
tele-operations and immersive education techniques - and the coming availablity
of this at cost levels affordable for home use.
And, it was a lot of fun!
Diaspar Virtual Reality Network
424 Glenneyre
Laguna Beach, California 92651
714 831-1776
Internet: diaspar.com (or 192.215.11.1)
9600 bd.: 714 376-1234
2400 bd.: 714 376-1200
000287|David42 |032593|013049|Diaspar|Let's Talk
Frankly, it was a lot of fun. There are no international barriers when
scientists do fancy footwork to keep from having model cars run amok. While
there are serious sides to finding low cost ways to tele-operate vehicles of
all kinds, there is something about this that appeals to the kid in all of us.
My goal was to bring home the point that we are on the verge of a revolution
that will profoundly touch all of us in a personal way in our own homes. Used
properly, we have enormous potential to learn new things, go places never
before possible and to test the limits of our imagination.
=============================================================================
Permission is hereby given to cross-post the above provided it is posted in
its entirety and is unaltered.
=============================================================================
------------------------------
Date: 25 Mar 93 19:17:18 GMT
From: fred j mccall 575-3539 <mccall@mksol.dseg.ti.com>
Subject: NASA and Congress
Newsgroups: sci.space
In <C44DD2.6Dt.1@cs.cmu.edu> 18084TM@msu.edu (Tom) writes:
>I see the point about enourmous scope, and the very real problems that
>can and do occur, but I have a real problem with 'only the gov can...'
>For one thing, gov only gets it's $$ from citizens or inflation, so
>it's patently fallacious to say that only gov can afford it.
Ok, Tom, how about "only government can *realistically* afford it,
because only someone with that kind of coersive power can collect
sufficient money in one place and commit to spending it on one thing"?
[Long book of libertopian diatribe deleted ...]
--
"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 18:47:26 GMT
From: nsmca@acad3.alaska.edu
Subject: Orbital Skysurfing Club/DTO...
Newsgroups: sci.space
Anyone want to start a Skysurfing Club, I know its a little bit easrly for
this, but this is a Development Test Objective idea club/think tank idea.. Who
wants to be Club President or Email contact site??
==
Michael Adams, nsmca@acad3.alaska.edu -- I'm not high, just jacked
------------------------------
Date: 25 Mar 93 13:43:39 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Predicting gravity wave quantization & Cosmic Noise
Newsgroups: sci.space,sci.astro,sci.physics,alt.sci.planetary
In article <C4Fpup.EJF@murdoch.acc.Virginia.EDU> crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass) writes:
> And yet we're talking about gravitational waves with frequencies
> around 10^-4 Hz. I also don't know if we can treat
> gravitational waves as if they were some sort of moving slinky.
> Time would seem to change too, and that always complicates things
> (especially my being able to visualize it). Let's say you
> lengthen the path on the expansive part of the wave, thereby
> decreasing the frequency. However, while the gravitational
> disturbance is doing this it also would seem to be slowing the
> local 'time standard'. If this happens, it seems that the
> frequency one would count locally is still the same as the
> 'original' frequency.
>
> Anyway, I can also convince myself as the wave crests and
> falls and crests, it alters the local time standard accordingly to
> cancel the wavelength shift. Please, convince me differently.
During a "trough" or expansive part as you call it, the local G field
strength is lowered. Space expands, and time goes faster. During the
"crest" or compressive phase, space is contracted, and time goes
slower due to the high local G field. As you can see, the two effects
complement each other instead of opposing each other vis doppler.
Gary
--
Gary Coffman KE4ZV | You make it, | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems | we break it. | uunet!rsiatl!ke4zv!gary
534 Shannon Way | Guaranteed! | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244 | |
------------------------------
Date: Thu, 25 Mar 1993 14:01:07 GMT
From: "Thomas E. Smith" <tes@motif.jsc.nasa.gov>
Subject: Predicting gravity wave quantization & Cosmic Noise
Newsgroups: sci.space,sci.astro,sci.physics,alt.sci.planetary
crb7q@kelvin.seas.Virginia.EDU (Cameron Randale Bass) writes:
>In article <1993Mar25.014429.10077@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes:
>>>But that brings up a point. What is the relativistic interaction between two
>>>waves moving at light speed? How do they view eachother?
>>
>>I wish there were an easy way to pass drawings in this medium. It would
>>make explanations so much simpler. First lets clear up some differences
>>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.
>>rolling on a rubber sheet. Now EM waves are transverse oscillations
>>of electric and magnetic vectors at right angles to each other and to
>>the direction of travel. When the EM wave encounters the G wave, all
>>the EM wave "sees" is a change in path length. I don't know what in
>>hell the G wave "sees".
>
> Why doesn't the EM wave see a change in local time?
It ought to. Gravity redshifts the EM wave in part by slowing the wave's
local time.
>
> dale bass
------------------------------------------------------------------------------
| 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: Thu, 25 Mar 1993 13:35:46 GMT
From: "Thomas E. Smith" <tes@motif.jsc.nasa.gov>
Subject: Predicting gravity wave quantization & Cosmic Noise
Newsgroups: sci.space,sci.astro,sci.physics,alt.sci.planetary
gary@ke4zv.uucp (Gary Coffman) writes:
>>That brings up a point. What is the relativistic interaction between two
>>waves moving at light speed? How do they view eachother?
>
>I wish there were an easy way to pass drawings in this medium. It would
>make explanations so much simpler. First lets clear up some differences
>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
>rolling on a rubber sheet. Now EM waves are transverse oscillations
>of electric and magnetic vectors at right angles to each other and to
>the direction of travel. When the EM wave encounters the G wave, all
>the EM wave "sees" is a change in path length. I don't know what in
>hell the G wave "sees".
When I say how do they "view" eachother, I mean to the EM wave, how fast is the
G wave going. The speed of light is supposed to be constant no matter who is
doing what.
Consider the velocity transformation of special relativity:
velocity' = velocity / sqrt(1 - (v^2)/(c^2))
velocity' = velocity / 0 <-- if v = speed of light, c
velocity' = infinity??!!
The same thing happens to time dilation, and mass becomes undefined. So my
question is how do you figure out how the gravity wave is affecting the EM
wave with all these infinities, and undefines? With relativity involved, it
isn't as simple as interactions between sound waves.
------------------------------------------------------------------------------
| 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 93 18:24:24 GMT
From: nsmca@acad3.alaska.edu
Subject: Robots, BASE, help..
Newsgroups: sci.space
Way around many of the problems of robotic remoteness is to have a two faze
system.. Have a base computer that controlls or provides guidance for all the
robot minion.. So that when the robot minion get in trouble they don't have to
ask for help from earth. Or maybe the BASE can send another robot to help get
the first out of the jam it got "it self" into to.. I know this might be beyond
current tech for now.. But.. is it truly beyond or just not been thought of.
If the BASE needs help, it then asks earth.. You can program certain responses
that the BASE can provide to the Remote (kind of like whena car gets stuck in
snow, there is certyain things to do to get out the easiest)...
==
Michael Adams, nsmca@acad3.alaska.edu -- I'm not high, just jacked
------------------------------
Date: 25 Mar 93 17:20:20 GMT
From: Henry Spencer <henry@zoo.toronto.edu>
Subject: Rocket clones: reduce risk of introducing new tech
Newsgroups: sci.space
In article <1993Mar25.023047.10505@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes:
>>>>As witness Pegasus, it *is* possible to create a new payload class with
>>>>a new launcher.
>>>Scout, and Ariane multiple satellite launch systems, had already created
>>>the Pegasus payload class...
>>Then why weren't any being launched? ...
>>It was Pegasus that made this payload class real.
>
>Pegasus has launched two payloads, to wrong orbits.
Gary, you're behind... Pegasus has launched ten payloads on three launches.
Four of them ended up where they were supposed to go, on launches 1 and 3.
The six microsats on launch 2 did end up in a lower-than-intended orbit.
None of which has anything to do with refuting my contention. The customers
are lining up for Pegasus, not for Scout or Ariane-piggyback.
>Ariane has
>launched 16 of the 23 amateur radio sats, six at once on the last
>launch. Almost every Ariane launch is a multiple payload launch.
>You must have a lot of fingers. :-)
Almost every Ariane launch carries two *large* payloads, but no small ones.
The only time when Ariane carries Pegasus-class payloads is when it has
spare payload mass, which is rare in its normal role as comsat-hauler.
Especially so since the advent of Ariane 4, which has six different
strap-on configurations so the customers pay for only as much lift
capacity as they need.
>As of 1988, Scout had successfully put 95 Pegasus sized payloads
>into orbit at $10 million each (1988 dollars). Recently Scout has
>launched Macsat, Salt, USAF-1, Small Expl-01, Small Expl-02, and
>CRRES-01.
This must be some new definition of the word "recently" that I haven't
encountered before. :-) Actually, you left out MSTI-1, which went up
on Scout not long ago... but it's been damn near the only Scout launch
in recent times. The production line is shut, there are only one or
two of them left in storage, nobody has any idea whether or when they
will resume production. Least of all the LTV people you talk to about
commercial launches -- we looked at Scout for the Canadian Solar Sail
Project, and I was in charge of launcher evaluation.
>Work is underway by the Italian space agency to couple
>Ariane SRBs to Scout, making a Scout II with double the payload
>capacity.
Actually, there are two different souped-up-Scout projects in Italy, and
it is not at all clear whether either of them will end up flying.
>... NASA has 8 Scout
>launches scheduled between now and the end of the decade.
Sure about that? Last time I looked, there were only three Scouts left,
and no plans to build more. I strongly suspect that those are not Scout
launches, but Scout-*class* launches... most of which are likely to end
up on Pegasus.
>At less
>than half the cost of Pegasus, Scout can, and has, reliably delivered
>lightsats to orbit for 33 years.
Then why are all the customers going elsewhere? The modern lightsat
builders see Pegasus as the launcher of choice; it was the availability
of Pegasus that really got the lightsat boom going.
--
All work is one man's work. | Henry Spencer @ U of Toronto Zoology
- Kipling | henry@zoo.toronto.edu utzoo!henry
------------------------------
Date: 25 Mar 93 19:00:41 GMT
From: fred j mccall 575-3539 <mccall@mksol.dseg.ti.com>
Subject: Russia's OPERATIONAL Starwars Defense System
Newsgroups: sci.space
In <1993Mar24.154802.5198@cnsvax.uwec.edu> mcelwre@cnsvax.uwec.edu writes:
>
> RUSSIA'S OPERATIONAL STARWARS DEFENSE SYSTEM
Didn't we just see this crap a week or two ago? It's bad enough to
get shotgunned with this dreck; the least he could do is post
*different* garbage.
I don't suppose anyone could make a case for this being a commercial
use of the net to advertise for Dr. Beter's Audio Letters, or whatever
it was?
> UN-altered REPRODUCTION and DISSEMINATION of this
> IMPORTANT Information is ENCOURAGED.
> Robert E. McElwaine
> B.S., Physics and Astronomy, UW-EC
I am *really* starting to wonder about the academic reputation of this
school, what with Mr McElwaine claiming to have a BS in Physics and
Astronomy from it. Can anyone who's had any sort of real education
actually believe the manure he innundates the net with? Can't anyone
convince him to post this sort of silliness to some more appropriate
newsgroup?
--
"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 19:14:18 GMT
From: fred j mccall 575-3539 <mccall@mksol.dseg.ti.com>
Subject: SDIO VS NASA (was Re: Retraining at NASA)
Newsgroups: sci.space
In <1993Mar18.193335.11630@iti.org> aws@iti.org (Allen W. Sherzer) writes:
>Even without SSTO, SDIO spends half to a third of what NASA does to send
>a pound to LEO. Yet they both use the very same launchers in many cases
>and launch similar payloads.
Isn't this due primarily to having an exemption from FARs? I recall
GD testified to Congress that they could start delivering vehicles for
half what they charge now if they didn't have to meet FARs.
--
"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 18:27:46 GMT
From: nsmca@acad3.alaska.edu
Subject: Space Posters, and where to get them?
Newsgroups: sci.space
Wiers question, where is a good place to get Space Posters??? I know that many
people seem to like posters of movie stars and such, beer (sexy girls okay),
and other such things, I was wondering if someone has any Space Posters and
where to get them?
==
Michael Adams, nsmca@acad3.alaska.edu -- I'm not high, just jacked
------------------------------
Date: 25 Mar 93 17:55:36 GMT
From: Russ Brown <russ@pmafire.inel.gov>
Subject: temperature of Lunar soil
Newsgroups: sci.space
In article <C4FErn.A12@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>In article <1993Mar24.154822.9922@pmafire.inel.gov> russ@pmafire.inel.gov (Russ Brown) writes:
>>>(This is why we can separate day-night variation from steady-state
>>>temperature. The day-night variation is zero at the depths in question.)
>>
>>The measurements above 1.5 m were subject to the constantly changing
>>surface conditions.
>
>You're overestimating this greatly. The temperature variation at a
>depth of 0.5m is only a few degrees, and it tapers off to zero at
>maybe 0.8m. (These are directly measured results from the Apollo 15
>and 17 ALSEP packages, not extrapolations or theoretical speculation.)
>The regolith is a *really* good insulator.
>--
We don't disagree...although it may seem so. At 1.5 m, the temp _is_
essentially constant. The regolith is an excellent insulator, and the
effect of the 280K surface temperature variation is damped out as a fn
of depth.
My comments on calculations were a side comment, and were provided
as an observation that measurement and theory should be in excellent
agreement in this case. Besides, solving the differential equations
with moving boundary conditions is an interesting exercise.
------------------------------
Date: 25 Mar 93 09:09:22 GMT
From: Pat <prb@access.digex.com>
Subject: the call to space (was Re: Clueless Szaboisms )
Newsgroups: sci.space,talk.politics.space
Shari talks about SPS's.
I've read alot about SPS's, they seem like a good idea, etc, but
When I talk to my Utility Rep, their biggest area of investment is
in Negawatt Producers. No, that's not a typo. They make more
money, getting people to save energy, load shift, etc then they
make now selling power.
Nuclear Power proved to be a technological rathole. Nice in certain
areas, but Holistically not terribly useful. SPS's are in that
same area. Maybe Large scale infrastructure improvements will
help, but I worry about setting out for this Brunellian vision
without some other justification.
I'd rather see developement of other technologies for space,
and if it turns out to be SPS's, let it be SPS's. If it turns
out to be Crystallography, then it's Crystals....
Let's not set one target, let's set for a technological infrastructure
and let the market make ti.
Let's put 60 Million into the DC-y, rather then 60 Billion into
SPS's.
pat
------------------------------
Date: 25 Mar 93 04:25:45 GMT
From: Bill Higgins-- Beam Jockey <higgins@fnalf.fnal.gov>
Subject: Time Machine!?
Newsgroups: sci.space
In article <1993Mar25.014652.10162@ke4zv.uucp>, gary@ke4zv.uucp (Gary Coffman) writes:
> In article <davidlai.732993136@unixg.ubc.ca> davidlai@unixg.ubc.ca (David Lai) writes:
>>
>> I remember from my youth, I've been thinking of a time machine
>>which can go back to the past.
>
> Ah, Tipler machines and shuttling wormholes. The former is too large
> to contain in a galaxy, and the latter is killed by quantum evaporation.
> Anybody got a Tardis manual handy?
I saw one at a hamfest last year, but I couldn't talk the owner down
from fifty bucks. Too steep for me.
If you really want one, maybe the guy will be back next year. Go to
the annual Area 51 Hamfest in Nevada-- I think it's in June. You can
find some great buys on surplus junk and old documentation.
Bill Higgins | Every so often, Innumeracy
Fermi National Accelerator Laboratory | strikes. Out of all Americans,
Bitnet: HIGGINS@FNAL.BITNET | a lot suffer from it. But
Internet: HIGGINS@FNAL.FNAL.GOV | we can win the fight against
SPAN/Hepnet: 43011::HIGGINS | Innumeracy with your help.
| All it takes is a few pennies a day.
------------------------------
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From: Josh Hopkins <jbh55289@uxa.cso.uiuc.edu>
Subject: smallsat launches
Date: Thu, 25 Mar 1993 09:06:35 GMT
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gary@ke4zv.uucp (Gary Coffman) writes:
>>When people plan for such missions, the nominal launcher is almost
>>invariably Pegasus. Once in a while somebody mentions Scout. Launch
>>opportunities for small payloads on Ariane are scarce as hen's teeth.
>>It was Pegasus that made this payload class real.
>Pegasus has launched two payloads, to wrong orbits.
Actually, I think the number is about 11, on three launches (2,7 and 2 as I
recall). There's another scheduled for the end of April.
--
Josh Hopkins jbh55289@uxa.cso.uiuc.edu
"Tout ce qu'un homme est capable d'imaginer, d'autres hommes
seront capable de la realiser"
-Jules Verne
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End of Space Digest Volume 16 : Issue 369
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