Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V15_4/V15NO431.TXT

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Date: Tue, 17 Nov 92 05:08:10
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V15 #431
To: Space Digest Readers
Precedence: bulk


Space Digest                Tue, 17 Nov 92       Volume 15 : Issue 431

Today's Topics:
                 Automated space station construction
                  Free Middle/High School Broadcasts
                Lunar "colony" reality check (2 msgs)
Minority Kids into Techies (was Re: Free Middle/High School Broadcasts)
OS in the shuttle (was Re: What kind of computers are in the shuttle?)
                    Putting telescopes on the moon
                          Shuttle computers
                Shuttle replacement, STS-52 half-full
                         Space suit research?

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Date: 14 Nov 92 14:34:54 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Automated space station construction
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Bob Pendleton) writes:
>From article <[e-mail]>, by [e-mail] (Gary Coffman):
>> Military COBOL and Intel processors, FRED IS DOOMED. :-) :-)
>
>Get your history straight. COBOL was a US Navy project. The Air Force
>also had it's own programming language. ADA is the result of
>inter-service rivalry :-)

I called Ada military COBOL because it's almost as wordy. Actually I
like Ada and have coded some serious applications in it. It's C++ with
an attitude. :-)

Gary

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

Date: 16 Nov 92 22:35:18 GMT
From: "Patrick S. Golden" <[e-mail]>
Subject: Free Middle/High School Broadcasts
Newsgroups: sci.space

REACHING FOR THE STARS

A free, nationwide distance-learning program designed to
encourage young minority and female middle and high-school
students to pursue careers in science and engineering

2:00 p.m. - 2:30 p.m. (ET)

December 16, 1992
February 10, 1993
March 17, 1993
April 7, 1993
May 12, 1993

Program Description:
Each of the 30-minute programs in the five-part interactive series
will profile a different recipient of a Virginia Space Grant
scholarship or  fellowship.  These  young minority and female
researchers will describe what  motivated them to  pursue careers
in the sciences and engineering, what their lives are  like at the
college or university where they study, and what their career
aspirations are.   Each researcher will also teach a basic science
lesson and briefly  discuss the  relationship of that science lesson to
their university research  project.  Viewers  will have the
opportunity to ask questions of the young researchers  via
telephone  during an interactive segment of the program.  Pre- and
post- broadcast material  will be mailed to those registering for the
series.

Target Audience:  Middle school and high school students and
other interested viewers

Program Objectives:

The series is designed to provide viewers with:

- An awareness of the career possibilities and rewards that exist for
students --   particularly minorities and women -- in engineering
and the  sciences.

- A knowledge of the scholastic paths students must travel to
become engineers  and scientists.

- An understanding of the nature of five young minority and
female researchers'  college experiences and what viewers will
encounter if they attend  college and  major in the sciences.

- Knowledge of five basic science lessons and how those lessons are
related to  more sophisticated research.

Reaching for the Stars is a cooperative educational project of the
Virginia Space  Grant Consortium, Old Dominion University and
the National  Aeronautics  and Space Administration.

For Registration Information:
Old Dominion University's Academic Television Services at  (800)
548-4807

VIRGINIA SPACE GRANT CONSORTIUM
2713-D Magruder Blvd.
Hampton, VA  23666
[phone]
E-mail: [e-mail]
--
|-------------------------------|
|++Patrick Golden++             |
|Virginia Space Grant Consortium|
|[e-mail]       |

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

Date: 16 Nov 92 22:54:48 GMT
From: Jared Dahl <[e-mail]>
Subject: Lunar "colony" reality check
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] writes:
|>
|> 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?

Not cheaper though...

What really needs to be done is more research.  You don't just buy a
house after you drive by it a few times.  You go inside, look in the
basement and attic, check it out for termites.  We need to do the
same thing on the moon.  We need to start sending surveying missions
to located mineral deposits and volatiles.  Apollo taught us a lot
about the moon, but it was hardly enough.

--
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
| Jared Dahl             | "My heart is human, my blood is boiling, |
| Systems Programmer     |  my brain IBM"                           |
| IBM - Rochester, MN    |              -- STYX,  "Mr. Roboto"      |
=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=
Opinions expressed are mine, not IBM's.

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

Date: 13 Nov 92 18:33:54 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Lunar "colony" reality check
Newsgroups: sci.space,alt.sci.planetary

In article <[e-mail]> [e-mail] writes:
>In article <[e-mail]>, [e-mail] (Gary Coffman) writes:
>
>>The inverse square law is a hard master. A microwave array on the Moon
>>needs a gain 1,000,000 times that of an array at LEO to produce the same
>>beam on Earth's surface. A Lunar array needs to be 100 times larger than
>>an array at GEO and is available only 12 hours a day to any given site on
>>Earth, and receives solar power only 2 weeks a month.
>
>Wellllll, yes and no.
>
>You build more than one array. Build a bunch of them, since some are going to
>get wiped out by incoming garbage at some point in time :) Real estate is
>cheap.

Real estate may be cheap, I've got some swamp land..., but the labor and
site preparation are not.

>There's also some tricks you can do with the beam which you can't do with an
>SPS, but I don't have the references or the SEI guy here to remember exactly
>what you can do.

You can get *ground gain* from mounting the antenna closely over the Lunar
surface. But at best that only buys you 3 db. The array still needs to be
50 times as large as one at GEO.

>> It would take decades
>>of concentrated work to build a Lunar array after permanent manned presence
>>is established on the Moon, if the array is to be constructed from native
>>materials.
>
>Decades? You've been sipping from Szabo's cup, I see. :) The metals for
>rectennas (?) are easy enough to cook up and stamp/mold/whatever.

But first you have to mine them, build the processing plants, build the
machine shops, do site preparation, and actually install the equipment.
A Lunar base is unlikely to have more than a dozen workers at first, and
they will have other tasks, like staying alive, that will consume much
of their time. The infrastructure needed to do large scale mining, refining,
fabrication, and civil engineering needed to build a power system from
scratch is rather staggering. Let me drop you and a dozen of your friends
in the vastly more friendly environment of the Sahara desert and see how
long it takes you to build a multi-gigawatt power array and then transport
yourselves to the Gobi desert and build another and interconnect them.
I don't think Bechtel, with all their resources, could do it here in
less than decades.

Gary

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

Date: 17 Nov 92 05:47:11 GMT
From: "Michael V. Kent" <[e-mail]>
Subject: Minority Kids into Techies (was Re: Free Middle/High School Broadcasts)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Bill Higgins-- Beam Jockey) writes:

>Would it be simpler to ask white males, politely, *not* to become
>engineers?

This is already being done, on a large scale, in the aerospace industry,
though hardly politely.  Bottom left corner of sig says it all.

Mike

--
Michael Kent                                   [e-mail]
McDonnell Douglas                              Rensselaer Polytechnic Institute

Tute Screwed Aero Class of '92                              Apple II Forever !!

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

Date: 16 Nov 92 23:36:28 GMT
From: Marc Fournier - Admin <[e-mail]>
Subject: OS in the shuttle (was Re: What kind of computers are in the shuttle?)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>dead; the specs are stringent for a reason.  MSDOS doesn't qualify. :-)
>

    Speaking of MSDOS...NAWT!...what do they use?  An in-house
developed OS?  Some derived from existing OS's?

Marc


--
Marc G. Fournier      | R-node Public Access Unix running UnixBBS 1.10
Etobicoke, Ontario    | 416-249-5366   24hrs 7 days/week   network email
voice: 249-4230       | shell accounts available  2500+ newsgroups  FREE
[e-mail] | Telebit WorldBlazer/SupraModem2400/Cardinal 2400

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

Date: 17 Nov 92 03:26:58 GMT
From: Andrew Haveland-Robinson <[e-mail]>
Subject: Putting telescopes on the moon
Newsgroups: sci.space

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

>-But, you ask, so what?  Won't mixing the signals from the combined
>-telescopes in the array isolate the light from the planet?  Well, yes
>-and no.  You can boost the signal-to-noise ratio by an amount that's
>-proportional to the number of telescopes in the array.  That might
>-allow you to detect the presence of the planet, where you couldn't
>-otherwise.  But unless you start with a pretty clean signal in the
>-first place, there will be far too much noise to allow anything like
>-imaging of continents.
>
>Would speckle interferometry, or integration of the incoming signals over
>very long periods of time (hours to weeks) help with reception? (Other than
>the fact that planets move over such time intervals.)
>
>I think you've made your point that the resolution formula can't be extended
>out to infinity. I'd be interested in how far it *can* be extended with, say,
>100 high-precision 10-meter optical telescopes.
>
>John Roberts
>[e-mail]

Be good for SETI too - I expect the moon would act as an effective shield
against the electromagnetic crap emanating from our orbiting toilet... :-)

Just a matter of time I guess (<1,000 years?)

Andy.

+-----------------------------------------------------------------------+
| Haveland-Robinson Associates   | Email: [e-mail]         |
| 54 Greenfield Road, London     |        [e-mail] |
| N15 5EP England. 081-800 1708  | Also:  0621-88756 081-802 4502       |
+-----------------------------------------------------------------------+
>>>> Those that can, use applications. Those that can't, write them! <<<<
> Some dream of doing great things, while others stay awake and do them <

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

Date: 17 Nov 92 04:58:22 GMT
From: Pat <[e-mail]>
Subject: Shuttle computers
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (John Roberts) writes:
>
>-From: [e-mail] (Henry Spencer)
>-Subject: Re: What kind of computers are in the shuttle?
>-Date: 14 Nov 92 23:58:37 GMT
>
>-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.
>
>Do you recall how tight the lockstep is? I don't believe I've seen anything
>written on that since before STS-1.
>
>John Roberts
>[e-mail]

I think it was 1/2 a clock.  i believe every instruction is run at the same
time on each processor and when a computation is ready they go to the master
for comparison and validation.
one of the first shuttle flights was screwed up because IBM tested the
software ona ground test bed which had different cable lengths then the
shuttle and the propagation delay was putting the clock edges enough out that
they kept locking out the slave in each pair.  i think it was something
like this.  there are two control channels, each has a primary and backup
computer.  the backups kept going off-line and the mission got scrubbed.
i am sure henry knows the true details but thats how a guyt from IBM
explained it to me.

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

Date: 17 Nov 92 05:40:26 GMT
From: "Michael V. Kent" <[e-mail]>
Subject: Shuttle replacement, STS-52 half-full
Newsgroups: sci.space.shuttle,sci.space

In article <[e-mail]> [e-mail] (Brian Stuart Thorn) writes:

>P.S., I consider myself more than mildly supportive of the Space Shuttle,
>but when NASA starts flying half-empty Space Shuttles and saying "the mission
>was full", I get worried.

I was just trying to explain, not defend, NASA's position as I see it.  Both
ground control and the astronauts claimed that they were very busy and work-
ing 12 - 16 hour days.  They may not have had the crew time to support an
additional payload, I don't know.  I do know that payload volume is not the
only constraint.

I can think of several ways to work around the problem:

1) Launch the LAGEOS on a Delta.  This could have been done rather easily,
   in my opinion.

2) Launch IRIS on another or the same Delta.  This would have required a
   significant development that NASA may have had to pay for.  IRIS was
   developed as an upper stage for Shuttle commercial payloads.  After
   commercial satellites were removed from the manifest, NASA agreed to
   launch LAGEOS as its first and only IRIS payload.  This was probably
   important for international relations as I suspect, but don't know,
   that Italy wanted data on what is for it a substantial rocket develop-
   ment program.  Thus IRIS, not just LAGEOS, needed to be flown.

3) Add another astronaut to the crew.  If crew time was indeed the constraint
   as I suspect, that fact should have been obvious early enough to add a-
   nother astronaut to run the additional payload in the payload bay.

4) Make it an EDO flight.  Again, if crew time were the constraint, adding
   the EDO pallet would add another two man-weeks to the flight.

For reasons not obvious to me, NASA is only flying one EDO flight per year.
The incremental cost of making a regular Columbia flight an EDO flight is
rather low.  If it were up to me, Columbia would be flying EDO every flight,
even if half of it were nothing but astronauts floating around in LBNPs.

Mike

--
Michael Kent                                   [e-mail]
McDonnell Douglas                              Rensselaer Polytechnic Institute

Tute Screwed Aero Class of '92                              Apple II Forever !!

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

Date: 17 Nov 92 03:39:54 GMT
From: Frank Crary <[e-mail]>
Subject: Space suit research?
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Adam R. Brody ) writes:
>Actually, the latest I have heard is that cold plates will be used
>for cooling and the sole reason for high pressure is health.

Air cooling is also relied on, at least on the Shuttle: There is a
10-psi mode, used during EVA missions to reduce pre-breathing
requirements. Rockwell, however, was sufficiently concerned about
cooling at low cabin pressure, to have a clause written into the
contract: Rockwell has no responisbility what so ever for any electronics
failures related to low cabin pressure...

>The fact
>that people live in high elevations like Denver and Mexico City, where
>the atmospheric pressure is lower than sea level does not hold much weight.

Actually, Vail or Aspen at ~10 psi average, would be a better example
than Denver (~12 psi...) I have never understood why NASA doesn't
consider this fact relevant. I know the reason the Case for Mars IV
conference endorsed 14.5psi for Mars missions: NASA apparently likes
it and will probably be using that pressure in many existing systems
by the time a Mars mission is launched. Having two different pressures
is a _major_ pain, so the general consensus was to stick to 14.5psi...

                                              Frank Crary
                                              CU Boulder

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

From: Pat <[e-mail]>

Newsgroups: sci.space
Subject: Re: Space suit research?
Message-Id: <[e-mail]>
Date: 17 Nov 92 04:13:22 GMT
Article-I.D.: access.BxuEEB.1ow
References: <[e-mail]> <[e-mail]> <[e-mail]>
Sender: [e-mail]
Organization: UDSI
Lines: 32
Nntp-Posting-Host: access.digex.com
Source-Info:  Sender is really [e-mail]
Source-Info:  Sender is really [e-mail]

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Pat) writes:
>>What's the big push for a earth normal type atmosphere?
>>apollo, etc, ran fine on low pressure pure O2,  does better pressure
>>greatly improve cooling.  or are there long term bio effects????
>
>The cooling issue is a serious one.  Apollo didn't have that concern --
>since doing an EVA required depressurizing the entire cabin, air-cooled
>equipment could not be used at all.  This was okay, more or less, for
>Apollo, but simply isn't appropriate for a laboratory environment:
>air cooling is by *far* the easiest way to cool electronics, and the
>cost of the hardware goes way up without it.
>
>And yes, there is some concern about possible long-term biological
>effects, although there is little firm knowledge.
>--

I still dont understand?  Are there any times the shuttle would undergo a
planned cabin depress?  What i was wondering is why have the shuttle run at 14PSI
earth normal atmosphere?   if the shuttle ran on a mostly O2 atmosphere at
3-4 PSI  wouldnt all the pre breathe stuff become irrelevant?
Couldnt the equipment in the shuttle handle a low pressure atmosphere?
sure, it wouldnt cool as efficiently as 14 pSI, but larger fans should
cover the gap??????
    cant you air cool even if the air is a little thin?  i know jet aircraf
seem to manage wven with a crappy thin atmosphere at 100,000 ft.

ALSO in apollo were EVA's part of the planned mission?  sure on lunar landing,
but what about in flight for the command and service module.  were they
recovering sample panels or was this just emergency plans?

pat

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

End of Space Digest Volume 15 : Issue 431
------------------------------