Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_6/V16NO604.TXT

Internet Message Format | 1993-07-13 | 32KB

Date: Fri, 21 May 93 05:45:28
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #604
To: Space Digest Readers
Precedence: bulk


Space Digest                Fri, 21 May 93       Volume 16 : Issue 604

Today's Topics:
                      About the mercury program
                       G-force and hard drives
                  Ion-photon rockets, what are they?
                       murder in space (2 msgs)
                 Need help with Space Colony CFD task
                      Orion Spacecraft (2 msgs)
                     Over zealous shuttle critics
                    Philosophy Quest.  How Boldly?
                            R101 (2 msgs)
                 Satellite Capabilities-Patriot Games
                 Space Marketing -- Boycott (2 msgs)
            Space Marketing would be wonderfull. (2 msgs)
               Vandalizing the sky-something is moving
                              WaterWorld
               Why Government? Re: Shuttle, "Centoxin"

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----------------------------------------------------------------------

Date: Thu, 20 May 1993 20:19:37 GMT
From: Henry Spencer <[e-mail]>
Subject: About the mercury program
Newsgroups: sci.space

In article <[e-mail]> Leigh Palmer <[e-mail]> writes:
>Which brings us back to the fellow with the plastic box. At the appointed
>time our hero turned the crank. Unfortunately he turned it too hard, and
>it broke!

Hadn't heard of that one, but it does sound possible.  Such things don't
get much publicity, but apparently it is not that uncommon for an experiment
to be messed up because the astronaut(s) goofed.  (A lot of those guys are
not the type of people you would pick if you wanted careful compliance with
procedures laid down in advance -- you don't get to be an astronaut by
being humble and obedient.)

>Thus was demonstrated the importance of Man in space. A
>machine, after all, can't be expected to do science.

Correct. :-)  To quote Larry DeLucas, the first crystallographer to fly
in space:  "My being up there was important because so many conditions
that people expected would be right turned out to be off target... Just
extruding and drawing liquids in and out of a syringe is not what you
would expect..."  He saved several experiments on the USML-1 Spacelab
flight.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

------------------------------

Date: Thu, 20 May 93 18:07:57 EDT
From: Tom <[e-mail]>
Subject: G-force and hard drives

fred j mccall 575-3539) writes:
>
>>Hmm.  I would think being on edge would be *worse*, since that might
>>make the tracks unsymmetrical around the spindle due to the sideways
>>force on the head.  Older drives used to tell you to reformat if you
>>were going to stand the drive on edge; at 3+g, this side force might
>>even be a problem for new drives.

Gary responds;
>Modern drives have embedded servo tracks. The G force on the heads from
>a track to track seek are substantially greater than 3G. The servo can
>cope. Head loading on the platter is another matter. It's regulated by
>Bernoulli forces of trapped air flow. There's no servo to keep the spacing
>constant. I don't know if 3G is enough to cause a head crash, but it might
>be.

I can't see 3g being a problem for any orientation.  As Gary said, the
heads are supported by an 'air bearing', which not only holds the, at
most, one ounce heads off the platters, but also resists the springs
in the head unit which keeps the air bearing small enough to still
read the drive.  The force of those springs dominates the weight of the
head, and probably would under 3-G conditions, since only the weight
of the head would change, not the force of the springs.

Like this:                G \/
                                           Head
               Platter                      __----------------------
               ----------------------------------------      Head unit

Sideways, the tripled weight of the heads will have a pretty hard time
deforming the head unit since the heads weigh so little and the head
supports are small flat triangles, with the flatness parallel to the
force of gravity.  There would certainly be *some* transformation, but
it's size, coupled with the fact that the deformation would be parallel
to the tracks, rather than in such a way to change tracks, suggests that
the effect would be infintesimal.

                                           |
Like this:               __                 |        ______
                        /  \      Head______---------
                       |    |       **______
                        \__/                ---------______
                                   G\/      |
                     Platter               |


Unless you are talking about the sideways orientation where the head
positioner is moving up and down, rather than side to side, but Gary
covered that.

Older drives did suggest low-level formatting in the position the
drive would be used in, but they also suggested reformatting every
3 months or 1000 hours of operation, too, meaning that position didn't
change the fact that older drives were unrealiable :-)

I've even had unreadable drives that were recoverable enough to backup
once they were flipped or turned on their sides.  They may have worked
fine after that, but no-one I know would have trusted them past backing
up for the replacement, so I can't be sure.

The way I understand it, the degeneration of the LL format is due to
changes in the spindle and platter holes, rather than the drive heads,
so, though 3-g will certainly cause some decrease in reliability, I
think it would be rather small, in any orientation.  How small, or
which orientation would be worse, I wouldn't try to say without
experiementation.  Drives made by different manufacturers would probably
show wildly different changes under 3-G conditions.  Some drives have
problems under 1-g conditions, and judging by how often it happened,
probably would have trouble under 0-G conditions.

Testing computer equipment under 3-G conditions would make an
interesting project.  Anyone know of a centrifuge with 110v, 15 amp
electrical, humidity and temp control, and a little room to set up in,
spinable to 3-g for days at a time? :-)

-Tommy Mac
-------------------------------------------------------------------------
Tom McWilliams 517-355-2178 wk   \ They communicated with the communists,
[e-mail] 336-9591 hm \ and pacified the pacifists. -TimBuk3
-------------------------------------------------------------------------

------------------------------

Date: Thu, 20 May 1993 20:35:43 GMT
From: Henry Spencer <[e-mail]>
Subject: Ion-photon rockets, what are they?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gopinath Kuduvalli) writes:
>In the late sixties and early seventies, when space was considered the
>next frontier to explore, there were a number of ideas of floating around
>as promising for long distance space travel. One of the concepts heard at
>that time was called "ion-photon rocket," if I remember right...

I suspect the "-" should be a "/"; those are two separate concepts.  (At
least, I've never heard them combined.)  They come under the general heading
of electric propulsion.  An ion rocket ionizes some material and uses strong
electric fields to accelerate the ions to high velocities.  The exhaust
velocities can be very high, giving very low fuel consumption; the problem
is that thrusts are low and power-system masses high, giving very low
acceleration.  The photon rocket uses light itself as the exhaust, giving
an extremely high exhaust velocity, but exceedingly low thrust for any
realistic amount of power.

Ion rockets have been tested in the laboratory, and even a little bit in
space, but have not yet seen major use.  (They are being seriously talked
about, and may even have flown by now, as station-keeping thrusters for
comsats -- a perfect application for low-fuel low-thrust engines -- but
proposals for using ion propulsion for missions like a comet rendezvous
so far have not been funded.)  Photon rockets are a theoretical concept
only, far away from any practical use.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

------------------------------

Date: Thu, 20 May 1993 19:15:21 GMT
From: mildred l perkins <[e-mail]>
Subject: murder in space
Newsgroups: sci.space

In <[e-mail]> [e-mail] (Achurist) writes:


>If you murdered someone in space, whose juristiction is it. i.e who
>will prosecute you for it? The boundaries of individual countries
>stop in the upper atmosphere so what happens???


>Akurist.

An interesting primer on the subject is the book "Outer Space, Outer
Sea, Outer Land and International Law" by J.N. Singh.

------------------------------

Date: Thu, 20 May 1993 20:12:28 GMT
From: Henry Spencer <[e-mail]>
Subject: murder in space
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Anselm Lingnau) writes:
>> In 2010, A. C. Clarke has the Russians prohibited from boarding Discovery
>> on the grounds of it being US government property.
>
>Wouldn't Discovery (with nobody on board besides HAL, a computer) be an
>abandoned vessel which anybody could pick up for its scrap value?

As I recall, space law differs from sea law in this area.  The country
that launches it, owns it until reentry or doomsday.

This is a stupid approach, and it will probably end up being changed
eventually (especially with the USSR no longer around as the champion
of state-owned everything), but right now it's still in effect.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

------------------------------

Date: Thu, 20 May 1993 20:11:08 GMT
From: Al Globus <[e-mail]>
Subject: Need help with Space Colony CFD task
Newsgroups: sci.space

I'm working on a large space colony design.  It features a stationary
exterior pressurized cylinder with shielding and rotating habitat
module(s) inside.  The rotation produces 1-psuedo g at the rim.

My problem: I'd like the habitat module to rotate in an atmosphere,
but I'm not sure of the consequences of the resulting fluid flows.  As
the radius of the habitat may be between 250-1000m, the tip speed is
between 60 and 240 miles per hour (at 2 and 1 rpm respectively).
Obviously, one can't have 200 mph winds ripping through the colony.
Thus, I need to understand the fluid flows generated.  Otherwise, the
habitat module must be a pressure vessle and rotate in a vacume with
an elaborate mechanism to get people and materials from the habitat to
the pressurized, non-rotation construction area.

I have looking into this problem enough to know that it would take me
many months (or a few years) to develop the CFD expertise necessary to
solve the problem.  I'm hoping someone out there has the CFD expertise
and would be willing to work with me to figure this out.  Needless to
say, there are a lot of issues to address.

Thanx.

------------------------------

Date: Thu, 20 May 1993 17:41:51 GMT
From: Robert Martin <[e-mail]>
Subject: Orion Spacecraft
Newsgroups: sci.space

[e-mail] (Colby Hayward) writes:

>    This is sort of a crossover from a question I asked on sci.military;
>If anyone here has heard of the proposed Orion spacecraft, they may be
>wondering the same thing.

>    Apparently, the Orion has a large "pusher plate" (read: shock
>absorber) built into the rear of the vessel.  It propels (sp?) itself by
>dropping nukes out the back, and detonating them at (relatively) short
>range.  The shockwave is supposed to propel the ship forward.

>    WHAT shockwave?  Aren't we in near vaccuum, here?  :)

In vacuum, it would be the outrushing mass of the nuke itself.  A LOT
of energy is released by the reaction, and some of it goes into
accelerating the reaction debris.  When that debris collides with the
pusher plate, momentum is transferred.


--
Robert Martin       | Design Consulting   | Training courses offered:
R.C.M. Consulting   | [e-mail]  |   Object Oriented Analysis
2080 Cranbrook Rd.  | Tel: [phone] |   Object Oriented Design
Green Oaks IL 60048 | Fax: [phone] |   C++

------------------------------

Date: Thu, 20 May 1993 20:28:56 GMT
From: Henry Spencer <[e-mail]>
Subject: Orion Spacecraft
Newsgroups: sci.space

In article <[e-mail]> Leigh Palmer <[e-mail]> writes:
>I visited the Smithsonian National Air and Space Museum hoping to see
>the film of the Orion test I had been told* was showing there...
>... A curator assured me that they did not have a film of the
>experiment...

My apologies -- my memory must have failed me on this one.  It *has* been
quite a while since that visit to the NASM.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

------------------------------

Date: Thu, 20 May 1993 20:23:50 GMT
From: Henry Spencer <[e-mail]>
Subject: Over zealous shuttle critics
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Phil G. Fraering) writes:
>After the R-100 flew to Canada and back, and the R-101 crashed
>in France due to structural failure, the government declared that
>Airships Were Obviously A Waste Of Time and therefore scrapped the
>R-100.

In truth, they did have *some* justification.  The R-100's maiden voyage,
although successful, did uncover non-trivial bugs that needed fixing.
And with the Great Depression just starting, and the government looking
at plummeting tax revenues and rising expenses, they were probably happy
to have an excuse to terminate funding for a speculative high-tech effort.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

------------------------------

Date: 20 May 93 19:19:03 GMT
From: Kevin Hart <[e-mail]>
Subject: Philosophy Quest.  How Boldly?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:
>In article <[e-mail]> [e-mail] (Dan Williams) writes:
>
>I was suggesting that bipedal locomotion requires a more complex brain
>than more stable bases. Whether one forces development of the other is
>subject to debate. I suspect a feedback occurs. If we want to end up with
>intelligence, we should prefer forms that encourage development of complex
>brains. Neither 2 nor 4 limbs offer unconditional stability in motion
>while the double tripod of the insect does.

I would think that it would be more useful to develop limbs for manipulation
than to develop any particular locomotion.  Complex things like hands would
require a complex brain.  And this complexity would be directly applicable
to the problem of tool use, whereas the complexity required for balance and
coordination would not.  The advantage of bipedal locomotion is the added
specialization of the forelimbs.  All IMO.

>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     |                     |


--
Reduction of population.  Like lemmings.  And an outlet for excess
testosterone which was once useful to the defense of our
hunter-gatherer bands.  That's primarily what we get out of any war.
    -Lee Story   ([e-mail])

------------------------------

Date: 20 May 1993 19:57:37 GMT
From: "Palmer T. Davis" <[e-mail]>
Subject: R101
Newsgroups: sci.space

In a previous article, [e-mail] (Del Cotter) says:
>
>[R101 is] a long, sad tale, heartbreakingly similar to the Shuttle story,
>leading up to the events of 28/1/86 (I don't need to go to any reference
>for that date).  I will just give the final paragraphs of Shute's
>account:
>
> [R101 crash blamed on rotted fabric]

While the fabric problem may have contributed to the disaster, it wasn't
R101's only problem.  The ship was poorly designed and badly handled,
and probably would not have reached India, even if the fabric had been
replaced.  The diesel engines made her far too heavy, the extra bay that
was added (in the same fashion as the ill-fated R38 that R101's design
team had also produced) weakened the frame, the gas cells chafed against
each other and against the airframe, and were made of single-ply fabric,
and the ship was rushed into service before she was airworthy.  The R100,
built by a rival team, had made a successful flight to Canada two months
earlier, the depression meant that only one design team would likely be
retained, and Lord Thomson, the Secretary of State for Air, demanded that
the R101 take him to India by early October and keep to a foolishly
ambitious schedule.  The Air Ministry had been crowing about how safe and
advanced R101 would be for years (Thomson: "The R101 is as safe as a house,
except for the millionth chance.").  And finally, her skipper took her
right into a squall at low altitude.

While the deteriorating fabric and deteriorating SRB O-rings are similar,
and there was pressure on both vessels to fly in very marginal conditions,
the R101 had half a dozen glaringly obvious problems, and had been having
trouble for months.  By contrast, the Space Shuttle had been flying
successfully for almost five years with few indications of trouble.
(Granted, those that there were were ignored.)  A better parallel for the
end of the R101 would be the voyage of RMS _Titanic_ a generation earlier.

-- PTD --
--
Palmer T. Davis      ___      UN-altered REPRODUCTION and DISSEMINATION of
<[e-mail]>   \X/   this IMPORTANT Information is ENCOURAGED.

------------------------------

Date: Thu, 20 May 1993 20:40:47 GMT
From: Henry Spencer <[e-mail]>
Subject: R101
Newsgroups: sci.space

In article <1tgnri$[e-mail]> [e-mail] (Palmer T. Davis) writes:
>While the fabric problem may have contributed to the disaster, it wasn't
>R101's only problem...

I once saw a quote from N.S. Norway (aka Nevil Shute) -- it may have been
from his book, I don't remember -- which summed up the basic difference
in approach between the R100 and R101.  He said that the R101 people had
funding that the R100 group could only dream about, and did things like
building complete mockups of complex areas of the design... but once they
made a decision, it was very difficult to change it.  The R100 people were
starved for resources, but could (and did) change their minds easily when
some promising approach turned out to be a mistake.
--
SVR4 resembles a high-speed collision   | Henry Spencer @ U of Toronto Zoology
between SVR3 and SunOS.    - Dick Dunn  |  [e-mail]  utzoo!henry

------------------------------

Date: Thu, 20 May 1993 20:25:58 GMT
From: Scott Smith <[e-mail]>
Subject: Satellite Capabilities-Patriot Games
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Charlie Prael) writes:
[bunches of drivel that I wrote deleted]
>
>Scott-- You're ignoring several things that make live 30fps video
>realitstic.  Those things are the military communications satellite array
>that is normally used for transmitting data.  The TDRS series, for
>instance, provide high data-rate transmission capabilities to both NASA
>and the USAF.  There's LOT of ways to get 30fps video down in realtime.
>
>------------------------------------------------------------------
>Charlie Prael  - [e-mail]
>Shakala BBS (ClanZen Radio Network) Sunnyvale, CA [phone]

Its not the communications problem.  I know that there could be designed
communications bandwidths large enough to transmit 30fps video
(Maybe we can even get stereo sound!-:).  The point
is thinking about the dwell time that a low earth orbiting satellite
is capable of over one spot on the earth.  There wouldn't be enough time
to get several minutes of video, the relative velocities are to great.

Its not the technological problems that are stopping things, its the
physics of the problem, just try keeping the spacecraft pointing at
one spot on the earth from the point that the spot is initially visible
to the where the location goes out of view.  I guess this is a greater
technological problem that I don't think is worth spending money on
when airplane assets could do it cheaper and more efficiently than
space assets.

--
Scott Smith
[e-mail]

------------------------------

Date: Thu, 20 May 93 15:01:43 CDT
From: Will Martin on 9000 <[e-mail]>
Subject: Space Marketing -- Boycott

It appears too few of the responders to this thread are considering
the audience any such advertising would be aimed at. A few seconds of

analytical thought by any potential advertiser will tell them that it
can't possibly reach enough viewers/recipients to be worth the cost, so
it is doomed from the start and will never happen.

Aside from the report that the actual proposed scheme would give a
result that couldn't even be discerned by the naked eye, let us assume
the proposal is for something that actually would be as big as the moon
in appearance. It would have to be at least that big to be effective as
an ad. But who would look at it?

Consider the target of advertising mass-market products, like, say,
Pepsi: basically urban dwellers in developed countries with disposable
income. (Sure, marketers advertise everywhere, including a general
store up a dirt road in the Amazon, but that's a trivial subset of
the total. The big bucks is devoted to the urban population today.)

These people DON'T LOOK AT THE NIGHT SKY! Sure, the astronomy and
nature buffs on the net do. The professional astronomers do. But Joe
Six-Pack and his teenage kids do NOT! Yuppie Jane and her kids do NOT!
Those are the targets of ads, and this medium won't reach them. Such
people spend 99.999% of the night-time under roofs -- house or apartment
roofs, car roofs, mall roofs, etc. They're not looking up during the
brief times they are going from their car to the store or into the
house, etc., and so they'll only catch a miniscule glimpse of any such
orbiting billboard when they look out the car window and it happens
to be near the horizon and unobscured by buildings or streetlights.
This isn't enough return to make the advertisers pay the cost of this
venture.

So don't worry about it. Even if it happens, it will be a money sink and
a failure and it won't happen again.

Will

------------------------------

Date: Thu, 20 May 1993 19:36:44 GMT
From: Dave Sill <[e-mail]>
Subject: Space Marketing -- Boycott
Newsgroups: sci.environment,sci.astro,talk.environment,talk.politics.space,sci.space

In article <[e-mail]>, [e-mail] (Frank Crary) writes:
>In article <1tc9kj$[e-mail]> [e-mail] (Walker Andrew John) writes:
>
>>    We've destroyed most of the Earth, can't we at least leave something
>>alone?We are supposed to be the most intelligent species, but sometimes
>>you have to wonder.
>
>We've destroyed the Earth?

Nope, read what he said, Frank.  The key word is "most".

>It was still there last time I looked.

Duh.

>... We've _changed_ the
>Earth, in some places quite radically. But suggest we've even
>come close to destroying it (i.e. made it uninhabitable to all forms
>of life) is probably the most arrogant thing I've heard in a
>long time.

That's an interesting definition of "destroy" you're using, and while it's true
that we haven't destroyed the entire planet, by that definition, we *have*
rendered large parts of it unihabitable by various species that inhabited them
before.  I consider that to be habitat destruction.

--
Dave Sill ([e-mail])                 Computers should work the way beginners
Martin Marietta Energy Systems           expect them to, and one day they will.
Workstation Support                                                -- Ted Nelson

------------------------------

Date: Thu, 20 May 1993 18:23:51 GMT
From: "Paul E. Reimer" <[e-mail]>
Subject: Space Marketing would be wonderfull.
Newsgroups: sci.environment,misc.consumers,sci.astro,sci.space,rec.backcountry,misc.headlines

In article <1tdpk5$[e-mail]>, [e-mail] (Jeffrey L. Cook) writes:
>The _only_ difference between this structure and any other proposed
>space structure is that this one would contain a commercial message.
>It might say "Coke" instead of "NASA".

I can't read the word "NASA" from the ground, in fact, I have to strain
to descern those satelites.

Paul Reimer
[e-mail]

------------------------------

Date: 20 May 1993 20:39:22 GMT
From: John Holeman <[e-mail]>
Subject: Space Marketing would be wonderfull.
Newsgroups: sci.astro,sci.space,rec.backcountry

Mr. Dellinger's account of his experience in Hawii brings back some memories
of last summer.  I was living with a friend in Livermore, CA when the lab
(Lawrence Livermore Natl. Lab) started testing the laser it was using to
research the ....ooohhhh, I can't think of the name of the thing...
variable something or 'nuther mirrors for astronomical telescopes...
anyhows.  When they were using the laser, you could see the bright red beam
reaching from the ground on up.  Being in one of the newer residential areas,
we(myself and my friend)  set up lawn chairs in the middle of the road so we
could watch.  We could only speculate what passing motorists thought when they
drove by and saw two guys sitting in lawnchairs in the middle of the street.
The next day we asked people at work if they had seen the laser.  Nobody had
a clue as to what we were talking about...oh well.

------------------------------

Date: Thursday, 20 May 1993 06:53:20 PST
From: Jon J Thaler <[e-mail]>
Subject: Vandalizing the sky-something is moving
Newsgroups: sci.astro,sci.space

[e-mail] (Phil G. Fraering) says:
> [e-mail] (Enzo Liguori) writes:

>> from What's new 14 May 1993, in sci.physics:
>>> 2. COALITION IS FORMED TO OPPOSE EARTH-ORBITING BILLBOARDS.
    (...mostly deleted...)
>>> The American Astronomical
>>> Society warns that the space billboard would hamper Earth-based
>>> astronomy, and Alice Harding, chair of the APS Division of
>>> Astrophysics, points out that it would also set a dangerous
>>> precedent for the unregulated commercialism of outer space.

> I knew the real reason they were against it wasn't because
> of advertising per se but the idea that commercial ventures
> have just as much rights to outer space as everyone else...

I think that the operative word in the APS statement is "unregulated."
It is obvious to me that when this spaceboard idea comes close to
a real proposal, it will be litigated to death.

------------------------------

Date: Thu, 20 May 1993 17:47:08 GMT
From: Robert Martin <[e-mail]>
Subject: WaterWorld
Newsgroups: sci.space

[e-mail] (Colby Hayward) writes:

>    On a rather sci-fi-ish note...

>    I occasionally like to (try to) write science fiction stories,
>usually based on hard science, with a bit of artistic leeway.  Mind you, I
>hardly ever finish them...  :)

>    Anyway, I was wondering what the conditions would be like if you had
>an Earthsized "planet", in Earthlike orbit, around a more-or-less Sunlike
>star, that was composed entirely of water.  The surface would be a normal
>ocean, but once you got past, oh say 20 miles deep, wouldn't strange things
>begin to occur?  The core would probably be some form of high-pressure ice,
>with various layers corresponding to various pressures, right?

>    Yet another strange concept from the mind of Me (tm).

An "Earthsized planet" made entirely of water, would have a much
smaller mass than the Earth.  UV from the sun would (slowly)
dissociate H and O.  Thermal engergy, mostly from the sun, but from
other sources as well, will accellerate these molecules.  Any that
attain the low escape velocity will leave the planet.

So the water world would shrink.  An the more mass it lost, the faster
it would shrink.

I don't think this would be a quick process, but eventually the
waterworld would cease to exist.

>/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\
>\  Colby Hayward; The Colbyashi-maru     /
>/              *Loopy*                   \
>\  aka [e-mail]  /                                     /
>/  What the hell is a sig, anyway?       \
>\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/

--
Robert Martin       | Design Consulting   | Training courses offered:
R.C.M. Consulting   | [e-mail]  |   Object Oriented Analysis
2080 Cranbrook Rd.  | Tel: [phone] |   Object Oriented Design
Green Oaks IL 60048 | Fax: [phone] |   C++

------------------------------

Date: Thu, 20 May 1993 19:50:58 GMT
From: Timothy J Brent <[e-mail]>
Subject: Why Government? Re: Shuttle, "Centoxin"
Newsgroups: sci.space,talk.politics.space

In article <1tghgs$[e-mail]> [e-mail] (Ken Hayashida) writes:

>Jim, do you want tens of thousands of people on welfare?  You and
>other liberal democrats want to cut defense spending, kill our nation's
>greatest assets in science and technology, put hundreds of thousands
>of skilled engineers + blue collar guys on the assembly lines out of
>work, and then tax us more.  Get a damn clue.  I am so sick and tired
>of this blantly false rhetoric about how bad the shuttle program is.

Boy, this guys a textbook example of how the Republicans were allowed
to screw us for the past decade or so (not that the Democrats will
likely be any better).  Why don't you try to take a more objective view
of the situation.

Sure defense spending promotes new technologies but so do the national
labs.  Sure they put people to work but they don't really earn us any
thing.  It's a kind of welfare in itself as it keeps people employed
yet does nothing to even out the trade deficit with other nations.
And guess what.  It's paid for by taxes.  Now, your deeply ingrained
Republican indoctrination should have set off bells at that.  If your
going to tax people why not spend more on developing marketable products.
Hell, we would do better to pump money into developing HDTV and maglevs
than B-2 and SDI.  Aren't you embarrassed that the Japanese are kicking
our butts in the electronics department?  Does it bother you that the
first commercial maglev in the world will operate in the US but be
of German origin?

We've been pumping money into defense for quite a while now and we've
done some great things.  But now, we must employ civilian technologies.
If we don't recapture our own markets we won't be a world power for long.

This is what you should be worried about (long term).  Not whether
your taxes will rise or the shuttle will be killed.  Remember your
children.

-Tim

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End of Space Digest Volume 16 : Issue 604
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