Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V15_4/V15NO424.TXT

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Date: Sun, 15 Nov 92 04:59:58
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #424
To: Space Digest Readers
Precedence: bulk


Space Digest                Sun, 15 Nov 92       Volume 15 : Issue 424

Today's Topics:
                  ALTERNATIVE HEAVY ELEMENT (2 msgs)
                           COSTAR (3 msgs)
                       Hubble's mirror (2 msgs)
                     Lunar "colony" reality check
                        NASA Coverup (4 msgs)
                          Shuttle computers
        SUMMARY of 1st NASA TOWN MEETING -- Raleigh NC (long)
                         UN Space/Moon Treaty
         What kind of computers are in the shuttle? (3 msgs)

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

Date: 14 Nov 92 18:31:00 GMT
From: Elling Olsen <[e-mail]>
Subject: ALTERNATIVE HEAVY ELEMENT
Newsgroups: sci.space

M>            A very simple experiment can demonstrate (PROVE) the
M>       FACT of "BIOLOGICAL TRANSMUTATIONS" (reactions like Mg + O
M>       --> Ca, Si + C --> Ca, K + H --> Ca, N2 --> CO, etc.), as
M>       described in the BOOK "Biological Transmutations" by Louis
M>       Kervran, [1972 Edition is BEST.], and in Chapter 17 of the
M>       book "THE SECRET LIFE OF PLANTS" [see Footnote] by Peter
M>       Tompkins and Christopher Bird, 1973:

Abstract of the report; S. Goldfein, Report 2247, Energy
Development from Elemental Transmutations in Biological Systems,
U.S. Army Mobility Research and Development Command, May 1978. DDC
No. AD A056906:

     "The purpose of the study was to determine whether recent
disclosures of elemental transmutations occuring in biological
entities have revealed new possible sources of energy. The works of
Kervran, Komaki, and others were surveyed, and it was concluded
that, granted the existence of such transmutations (Na to Mg, K to
Ca, and Mn to Fe), then a net surplus of energy was also produced.
A proposed mechanism was described in which Mg adenosine
triphosphate, located in the mitochondrion of the cell, played a
double role as an energy producer. In addition to the widely
accepted biochemical role of MgATP in which it produces energy as
it disintegrates part by part, MgATP can also be considered to be a
cyclotron on a molecular scale. The MgATP when placed in layers one
atop the other has all the attributes of a cyclotron in accordance
with the requirements set forth by E.O. Lawrence, inventor of the
cyclotron."
     "It was concluded that elemental transmutations were indeed
occuring in life organisms and were probably accompanied by a net
energy gain."

Can somebody tell me how I get a copy of the report?

Elling

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

Date: 15 Nov 92 02:28:00 GMT
From: Steve Masticola <[e-mail]>
Subject: ALTERNATIVE HEAVY ELEMENT
Newsgroups: sci.space

Elling Olsen writes:

       "It was concluded that elemental transmutations were indeed
  occuring in life organisms and were probably accompanied by a net
  energy gain."

I think the University of Utah should be very interested...

-Steve "Now where did I leave that palladium rod?" [e-mail].

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

Date: 14 Nov 92 15:51:01 GMT
From: George Wm Turner <[e-mail]>
Subject: COSTAR
Newsgroups: sci.space

>In article <[e-mail]>,
>    [e-mail] (John Roberts) writes:
>
>-From: [e-mail] (Pat)
>-Ball Aerospace is making costar, and it's  a prety interesting instrument.
>
>Are they the same company that makes mason jars? (The logo appears to
>be the same.)


yep,i don't know how large corporations work but, the ball family of
muncie, indiana is responsible for both them; muncie is also home
of ball state university.  i think david letterman has made some remarks
about muncie and when you talk about muncie, your talking about
the ball family/corporation/etc.  ball wields a lot of
finanical power in muncie.  i think the canning jars come from
muncie and costars is being built out in colorado. ball is involed
in many markets;  i think they also do some kind of medical work in
muncie.

    george wm turner   [e-mail]  [phone]

me, speak for iu; surely you jest?  these are just the opinions of a hoosier.

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

Date: 14 Nov 92 23:48:26 GMT
From: Henry Spencer <[e-mail]>
Subject: COSTAR
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (John Roberts) writes:
>-it's essentially three little mirrors on a sliding arm on a giant optical
>-bench (phone booth sized).  each of the little mirrors is calibrated
>-to adjust each of the intruments.
>
>There was a replica of COSTAR on display at the World Space Congress.
>I couldn't make head or tail of it...

The general outline isn't complicated.  Behind Hubble's mirror are four
big instruments, each phone-booth-sized, in a 2x2 array.  They view through
the hole in the center of the primary mirror, so looking through the hole
you'd see the innermost corner of each.  (I ignore some complications like
the WFPC and the fine-guidance sensors.)

COSTAR is mostly an empty box, originally built as a dummy instrument in
case one of the four wasn't ready for launch.  It will replace the High-
Speed Photometer (a pity, since this was the one instrument exploring a
totally unknown domain -- very-short-term variations in light output of
astronomical sources, down to the microsecond scale -- but it is clearly
also the least-used and most-expendable instrument).  The business end
is all stuffed into that innermost corner.

Basically, after COSTAR is installed, an assembly in that innermost corner
slides forward, into what is currently empty space in front of the four
instruments.  Then it deploys a complicated set of small arms, holding
two mirrors for each instrument -- one to catch the incoming light and
reflect it back forward, and another to intercept it and reflect it back
rearward into the instrument -- which have been very carefully ground to
take out (most of) the aberration.  It looks like a weird plant, with
arms sprouting out in semi-random directions, because the instrument
viewing apertures are in different places on each instrument.  (Luckily,
none of the apertures is very large, so small mirrors will suffice.)
All of this, of course, has to be very rigid and capable of very precise
adjustment by remote control.
--
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  [e-mail]  utzoo!henry

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

Date: Sun, 15 Nov 92 00:28:00 EST
From: John Roberts <[e-mail]>
Subject: COSTAR

-From: [e-mail] (John Roberts)
-Newsgroups: sci.space
-Subject: COSTAR
-Date: 14 Nov 92 03:04:57 GMT

--From: [e-mail] (Pat)
--it's essentially three little mirrors on a sliding arm on a giant optical
--bench (phone booth sized).  each of the little mirrors is calibrated
--to adjust each of the intruments.

-There was a replica of COSTAR on display at the World Space Congress.
-I couldn't make head or tail of it. (An explanatory video would have
-been useful, but I didn't notice one.)

NASA Select showed a video yesterday. Essentially, four of the instruments
are in "phone booth size" packages mounted at the end opposite the aperture,
apparently installed from the back. These instruments have small holes in the
front for the (off-axis) input from the secondary mirror to enter. One of these
instruments is the High Speed Photometer, which is replaced by COSTAR.

Once installed, COSTAR extends a triangular truss toward the front of the
telescope. This truss holds three small pairs of mirrors, one of each pair
facing the front of the telescope, and the other facing the back.

Once the truss is extended, it pivots about the leg closest to the
"centerwards" corner of the COSTAR box, apparently about 180 degrees,
swinging it more nearly in front of the other instruments. (The long axis
of the truss remains aligned with the long axis of the telescope.)

Once the truss is in place, the three pairs of mirrors swing out from the
truss to carefully assigned positions. Light from the secondary mirror
bounces off the front-facing mirror of each pair (situated toward the back
of the truss), then off the front mirror of each pair (located toward the
front of the truss), then into the original aperture of each instrument.
This therefore adds two reflections to the optical path of each instrument.
The angle and curvature chosen for the COSTAR mirrors presumably adds the
correction to compensate for the error in the primary, plus a correction
for the longer optical path, plus (I assume) a correction for the fact
that the front-facing mirrors have to be offset from the original aperture
openings, so the "off-axis angle" is different from what it originally was.

It's also necessary to block the original light path into the apertures.
This appears to be done by the rear-facing mirrors at the front of COSTAR,
which are rather large, and presumably painted black on the back.

That's just my interpretation of the video - corrections or amplifications
would be welcomed.

Also, I'm not sure where WF/PC is located relative to the other instruments.

Another video shows the making of the 1/3 scale MSU mockup of NASP.
It's hollow, and opens in the back - the wings stow inside for shipping.
Some of the techniques developed for the building of the model may have
further aerospace application. It's 50 feet long, and weighs 5000 pounds.

John Roberts
[e-mail]

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

Date: 14 Nov 92 15:03:48 GMT
From: "William H. Jefferys" <[e-mail]>
Subject: Hubble's mirror
Newsgroups: sci.astro,sci.space

In article <[e-mail]> [e-mail] writes:
#
#  The error was introduced into the main mirror because the setup used to
#test it was missing some spacers which were planned to locate the
#test rig at the correct focal point. Because the spacers were not present,
#the mirror was figured perfectly, but to the wrong focal point, outside
#the range of the Hubble's focusing apperatus. This error would have shown
#up had the entire telescope been tested as a whole prior to launch. Sadly,
#due to budget constraints, this was never done.

Baloney. The mirror has spherical aberration due to
the fact that the null corrector was mismanufactured.
To mismanufacture it, P-E had to put some spacers
IN that should NOT have been there. Hubble can
focus, but the spherical aberration prevents all
the light from being in focus at one time.

I'll agree, the error would have been caught if the primary
and secondary mirrors had been tested together. There are
lots of simple tests that would have caught the error.
None were used.

Bill

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

Date: Sun, 15 Nov 1992 00:14:02 GMT
From: Henry Spencer <[e-mail]>
Subject: Hubble's mirror
Newsgroups: sci.astro,sci.space

In article <[e-mail]> [e-mail] (William H. Jefferys) writes:
>I'll agree, the error would have been caught if the primary
>and secondary mirrors had been tested together. There are
>lots of simple tests that would have caught the error.
>None were used.

This is rapidly becoming a contender for Technological Myth Of The Decade.

If you look at what actually happened, rather than the popular mythology,
the fact is that three independent tests were run, and TWO OF THEM DETECTED
THE ERROR.  At which point, Perkin-Elmer management decided that the third
was more trustworthy than the other two, and ignored the two failed tests.

The *only* test that would have detected the error so unmistakably that
it couldn't have been ignored would have been an end-to-end test doing
real imaging with primary and secondary together.  This would *not* have
been a particularly simple or cheap test, thanks to various complications
like gravitational distortion of the primary, and it would have involved
a substantial risk of surface contamination.  NASA's decision not to do
it was probably a mistake, but it wasn't a particularly stupid or obvious
mistake, especially in a project that was behind schedule and over budget
already.  The mirrors had already been tested, successfully, in far more
sophisticated ways.  (NASA didn't know that the primary had flunked two
out of three tests.)
--
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  [e-mail]  utzoo!henry

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

Date: 14 Nov 92 20:27:00 GMT
From: [e-mail]
Subject: Lunar "colony" reality check
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] writes...
>> bias and not the state of knowledge in this area. Also underground water and
>> volatiles are a definite possiblity. What about carbonaceous meteor impact
>
>> areas? Would this not enrich the surrounding area and the underground where
>> the meteor penetrated with voliatiles or even water in the case of a comet?
>>
>
>
>Dennis... Have you considered lava tubes? They are old, they are permanently
>dark. If they are deep enough to get below the "permafrost" depth for the moon,
>we might well find volatiles in some extremely useful places. Right on your
>doorstep if you think like the Oregon L5 people. :-)
>
>I do not remember ever reading this idea in print. If it hasn't been then I
>want primacy on it. One problem I see is that the high thermal conductivity of
>the lunar surface. It might cause significant temperature swings even in
>permanently dark caverns.
>
>But if the temperature is right, there is nothing different between the
>proposed mechanism for volatiles to freeze out in polar craters. Cometary
>volatiles form a temporary atmosphere after an impact and most of it escapes
>except the small amount that happens to float into a cold trap. So could a good
>deep lava tube act as such a cold trap?
>
>This seems like a very, very interesting possibility.

I like it. I like it. Yea we have looked at Lava tubes. I have some great
pictures of lava tubes from Lunar Orbiter IV. This is a prime area for the
Artemis rover missions to the moon. No one knows what is down there and in
them.  One of the Apollo missions visited a collapsed lave tube(Hadley Rille)

Lave Tubes have been presented as a solution to the problem of a lunar habitat.
We could just go into the tubes and block of the ends however far apart we
wanted and seal em and set up shop. Would be kinda  boring after a while but
would be a good save haven from Solar flares. Lotsa possiblities on the moon
what is lacking is will power to accomplish the task. Would'nt this be a lot
more fun than war?

Dennis, University of Alabama in Huntsville

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

Date: 13 Nov 92 22:16:04 GMT
From: [e-mail]
Subject: NASA Coverup
Newsgroups: sci.space,sci.astro

In article <[e-mail]>, [e-mail] writes:
> Why do people still kling to the notion that we didn't actually go to the moon?...

Too many reruns of _Capricorn One_, no doubt.
> We went to the Moon....no doubts in my mind...
>
>                 James

God, I should hope so!
My old man made cassette tapes of the Lunar Landing of the TV (I didn't see it
myself...born 10 months later!).
I'd hate to think we've been holding on to 6 hours of junk!!!

==============================================================================
Mark Rickard -- Here for the duration.|[e-mail]| Go Bills!      |
------------------------------------------------------------------------------
"She wrapped herself in an enigma; there was no other way to keep warm."     |
==============================================================================

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

Date: 14 Nov 1992 14:18:58 GMT
From: Mark <[e-mail]>
Subject: NASA Coverup
Newsgroups: sci.space,alt.conspiracy

In message-ID: <[e-mail]> (Henry Spencer) writes:
>Oh, come now.  A conspiracy that large, held together for that long?  In
>a government that couldn't suppress Watergate or Iranscam?  Come now.
>This is laughable.

In article <[e-mail]> [e-mail] writes:
>   You  must  think  that  what  you  see on TV news is the entirety of what
>   really is going on in the world .  Now  some  might  find  such  naivete'
>   laughable, but I actually feel sorry for you.

Those astronauts sure must have faked their lightweightedness real good
seeing that the WHOLE THING WAS TELEVISED LIVE!

Sure fooled all of us!

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

Date: 14 Nov 1992 14:29:41 GMT
From: Mark <[e-mail]>
Subject: NASA Coverup
Newsgroups: sci.space,alt.conspiracy

In article <[e-mail]> [e-mail] writes:
(blah, blah)
>   Therefore,
>
>   The figure of 43,495 miles from the moon's center  for the neutral point
>   given  above  by  Time  magazine represents a relative gravitation of the
>   moon compared to the earth of approximately 64% !

Wrong.

Therefore, the figure of 43,495 miles implies that the moon has 1/6 the gravity
of the Earth at its surface.

Maybe next time, you'll see fit to include the Sun in your calculations instead
of repeating the mistakes of amateur rocket scientists.  Is it any wonder that
the first series of American and Soviet moonshots failed so miserably?

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

Date: 14 Nov 92 17:59:45 GMT
From: Patrick Chester <[e-mail]>
Subject: NASA Coverup
Newsgroups: sci.space,alt.conspiracy

In article <[e-mail]> [e-mail] (Edmund Hack) writes:
]In article <[e-mail]> [e-mail] writes:
]
]Good. It would have been unfortunate and embarassing for us to have been
]found out right now.  The AmAzIng NEUTRAL PARTICLE BEAMS were about
]ready for testing.  :-)

True. Don't want to miss that cyclone when we try to shoot it this time. :)

]>    I  will  continue , however to point out alternative theories to account
]>   for various facts  of  nature.  Theories  are  not  science,  but  merely
]>   suggestions  of  possible  explanations  for  observed  phenomena  .   An
]>   alternate theory need only be logically and mathematically consistent  to
]>   be as viable as relativity , or any other theory.
]
]No, what you have is necessary, but not sufficient.  It must also be
]testable and make some predictions about the universe to be as viable as
]relativity (General or Special). (This is true to first order.  I am
]aware that there is some discussion in philosophy of science about
]falsifiability, as well as other nits.)

It also helps to be a bit diplomatic snarfy. Saying NASA, you are BUSTED is
not the way to get anybody to listen to you. Indeed, you appear to be both
an arrogant ass and a raving loon when you use such phrases. It's not kissing
up to NASA when you avoid what you originally posted, snarfy; it's called
being polite. Now, if McElwaine would only follow that advice.

]No, no, no. NONE of Velikovsky's ideas are (at least as explained in the
]copy of "Worlds in Collision" I have) accepted in the mainstream of
]planetary and lunar science.  They are, in general, WRONG. Very wrong.
]As wrong as the Question to the Answer to the Ultimate Question of Life,
]the Universe and Everything.

The answers *not* 42? Then how do we even have a chance of knowing the
question?!



--
Patrick Chester            |----------------------------------------------------
[e-mail] |"The earth is too fragile a basket in which to keep
Politically Incorrect      |  all your eggs." Robert A. Heinlein
Future Lunar Colonist      |"The meek shall inherit the Earth. The rest of us
#^%$!! Militarist          |  are going to the stars." Anonymous
(Of the Sun Tzu mentality) |----------------------------------------------------

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

Date: Sat, 14 Nov 92 21:04:22 EST
From: John Roberts <[e-mail]>
Subject: Shuttle computers

-From: [e-mail] (I am a terminator.)
-Subject: Re: What kind of computers are in the shuttle?
-Date: 14 Nov 92 02:09:10 GMT
-Organization: University of Saskatchewan, Saskatoon, Canada

-In article <[e-mail]>, [e-mail] (John Roberts) writes:

-|> >From: [e-mail] (Peter E. Yee)
-|> Subject: STS-49 Press Kit (Forwarded)
-|> ...
-|>     The new GPCs use the existing Shuttle software with only subtle
-|> changes.  However, the increases in memory and processing speed allow
-|> for future innovations in the Shuttle's data processing system.
-|> Although there is no real difference in the way the crew will operate
-|> with the new computers, the upgrade increases the reliability and
-|> efficiency in commanding the Shuttle systems.  The predicted Rmean time
-|> between failuresS (MTBF) for the advanced GPCs is 6,000 hours.  The
-|> flight computers are already exceeding that prediction with an MTBF of
-|> 18,500 hours.  The MTBF for the original GPCs is 5,200 hours.
-|>
-|> New GPC Specifications
-|> Dimensions:         19.52" x 7.62" x 10.2"
-|> Weight:         64 lbs.
-|> Memory Capacity:     262,000 words (32-bits each)
-|> Processing Rate:     1.2 million instructions per second
-|> Power Requirements:      550 watts

-64 lbs? What's it made of? Lead?
-1 Mb?
-1.2 MIPs?
-0.5 kW?

-They want to put these in all the shuttles?
-Why not give them 3lb 20Mb 25 MIPs 0.25W 0.5 Gb hard drive laptops? Doesn't
-Compaq make laptops that can double for speed bumps? Just cross compile
-everything. You can probably buy a hundred computers for each of these
-heavyweights.

-Henry Choy
[e-mail]

There are more conventional personal computers on board the Shuttle, used
in the scientific experiments, etc. The reliability is nowhere near that
of the GPCs, and they are not entrusted with flying the Shuttle.

The most recent flight had one of the two main personal computers fail
(seized hard disk), and the Astro mission had *both* of the personal
computers dedicated to the scientific mission fail (heating problems),
which was why the astronauts had to work continually to update the
instrument positions. (At least manual control was available as a backup -
I understand some parts of the Shuttle flight *can't* be safely managed
under manual control, even disregarding the extent to which the manual
controls are routed through the computers.)

I think it would be false economy to get rid of a highly mission-critical
system that's been shown to be highly reliable and replace it with a
system that's known to be unreliable under space flight conditions,
just to save a few hundred watts and a few tens of pounds of payload.

The new GPCs are intended to be *more* reliable than the old ones, and
as I mentioned I believe that the greater capacity improves the ability to
handle abort modes.

Where did you get that 0.25W figure? The laptop we have uses a lot more
than that, and it also weighs much more than three pounds.

John Roberts
[e-mail]

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

Date: 14 Nov 92 23:17:44 GMT
From: "Allen W. Sherzer" <[e-mail]>
Subject: SUMMARY of 1st NASA TOWN MEETING -- Raleigh NC (long)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:

>    What about SSTO?  -- too many launch vehicle programs in the works.  Some
>        must be cancelled.

Did Goldin say this? If so, I'm disapointed.

>       All look favorable when first proposed, but
>        less so as they are costed out.

Perhaps but every assessment of SSTO says the concept will work. Even NASA's
internal assessment says: "...it is the opinion of the study team that a
SSTO vehicle can be developed for small payloads using a fail safe design
philosophy (assuming the contractor-specified engine performance)".

This evaluation didn't support the Delta Clipper design (IMHO this lack
of support had more to do with turf battles and NIH than quality of the
design). However, they DO say it can be done. Another internal NASA
assessment says that Delta Clipper could offer life cycle savings of
over $40 billion+ over the current alternatives.

Surely it's worth the cost of a couple of Shuttle flights to see if
the concept works?

>       Doubts the relevance of the
>        sub-scale DC-X test flight to the overall program.

The sub-scale DC-X performs the same role for DC-Y as the drop test
Shuttle Enterprise did for Shuttle. To quote the NASA assessment of SDIO
SSTO concepts: "The flip-to-vertical maneuver needs a high fidelity aerodynamic
and propulsion data base to support a six DOF analysis before its feasibility
ans associated landing accuracy can be ascertained".

DC-X exists to answer these questions (among others).

>       SSTO relies
>        heavily on poorly understood composites, some derived from NASP.

An Air Force project called Have Region has already built and tested many
of the cryogenic structures needed. They work. For about $15 million test
structures can be built and tested. Surely the offer of huge reductions in
launch costs are worth this small investment?

   Allen
--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves        |
|  [e-mail]     |  nothing undone"                                       |
+----------------------161 DAYS TO FIRST FLIGHT OF DCX----------------------+

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

Date: Thu, 12 Nov 92 14:39:00 PDT
From: Lauren Podolak <[e-mail]>
Subject: UN Space/Moon Treaty
Newsgroups: sci.space

TN>Now as to enforcement, well, if you can get there in the next 5 years, I thi
TN>you'd have a few years _at least_ before any government could even get
TN>anything there.  Think if you tried to set up a factory in Antarctica.  YOu'
TN>get kicked off pretty quick, and taken before some international court, all
TN>by an international military force.  This would be harder to do on the Moon,
TN>but if you had any sort of requirements from Earth, they'd starve you out to
TN>get you to come back.  If they did get up there, though, they'd probably
TN>bring enough force (eventually) to kick you off.

TN>There is one point though:  I don't think the U.S. ever
TN>signed the Moon Treaty.
TN>I'm not sure, however.  I also could have mis-stated what the Treaty actuall
TN>says.  This is what I remember, however.



Pretty close and it was never signed by the US......

James
___
 X OLX 2.1 TD X Who said that Interstellar Empires don't exit?

--
Internet: [e-mail]
UUCP:     ...!myrddin!tct!mechanic!Lauren.Podolak
Note: Mechanic is a free gateway between USENET & FIdonet.
      For information write to [e-mail]

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

Date: 14 Nov 92 16:55:11 GMT
From: Brad Whitehurst <[e-mail]>
Subject: What kind of computers are in the shuttle?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (I am a terminator.) writes:
>In article <[e-mail]>, [e-mail] (John Roberts) writes:
>|>
...
>|>
>|> New GPC Specifications
>|> Dimensions:         19.52S x 7.62S x 10.2S
>|> [I wonder what an "S" is? From context, I'd guess "inches". - JR]
>|> Weight:         64 lbs.
>|> Memory Capacity:     262,000 words (32-bits each)
>|> Processing Rate:     1.2 million instructions per second
>|> Power Requirements:      550 watts
>
>64 lbs? What's it made of? Lead?
>1 Mb?
>1.2 MIPs?
>0.5 kW?
>
>They want to put these in all the shuttles?
>Why not give them 3lb 20Mb 25 MIPs 0.25W 0.5 Gb hard drive laptops? Doesn't
>Compaq make laptops that can double for speed bumps? Just cross compile
>everything. You can probably buy a hundred computers for each of these
>heavyweights.
>
>Henry Choy

    I'm sure that they have to be rad-hard, vibration resistant,
and otherwise much tougher than Compaqs.  I seem to remember that the
old computer's memory was the old style magnetic "core" memory.  Is
that correct?  And what kind of memory does the new unit use?  That
could explain a lot of the power consumption!  I recall that when
designed, radiation induced errors in semiconductor RAM was a big
worry.  Somebody in the know can verify/correct this impression.



--

Brad Whitehurst    |   Aerospace Research Lab
[e-mail] |   We like it hot...and fast.

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

Date: Sat, 14 Nov 1992 23:58:37 GMT
From: Henry Spencer <[e-mail]>
Subject: What kind of computers are in the shuttle?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (I am a terminator.) writes:
>Why not give them 3lb 20Mb 25 MIPs 0.25W 0.5 Gb hard drive laptops? ...

They have hardened laptops, used for a variety of non-critical functions.

But apart from the reprogramming problem, the orbiter main computers have
to be just about the most reliable computer hardware ever built, capable
of *dependably* operating 100% despite radiation and intense vibration.
It would probably take five years just to certify those laptops to that
level of reliability, assuming they passed, which they probably wouldn't.
Remember, you can't even *control* the orbiter if those computers are
dead; the specs are stringent for a reason.  MSDOS doesn't qualify. :-)

There are also some other little problems, like the fact that the orbiter
computers aren't independent systems -- those five main computers operate
in very close lockstep for fault tolerance.  This isn't just a tougher
version of a commercial computer system.
--
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  [e-mail]  utzoo!henry

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Date: Sun, 15 Nov 1992 00:00:39 GMT
From: Henry Spencer <[e-mail]>
Subject: What kind of computers are in the shuttle?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Brad Whitehurst) writes:
>... I seem to remember that the
>old computer's memory was the old style magnetic "core" memory.  Is
>that correct?  And what kind of memory does the new unit use?  That
>could explain a lot of the power consumption!

The old ones used plated-wire memory, I believe.  (This was a relative of
magnetic-core memory, one that didn't catch on except in specialized
applications.)  The new ones use rad-hard SRAM memory.
--
MS-DOS is the OS/360 of the 1980s.      | Henry Spencer @ U of Toronto Zoology
              -Hal W. Hardenbergh (1985)|  [e-mail]  utzoo!henry

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End of Space Digest Volume 15 : Issue 424
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