Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v11_0/v11_042.txt

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Subject: SPACE Digest V11 #42

SPACE Digest                                      Volume 11 : Issue 42

Today's Topics:
        Re: measurement standards (aerospace)
            Re: private spaceplane
              Re: Measurement standards
             HASA select & Operacio 9000
            Re: Galileo Update - 02/12/90
Close-up inspection of Long Duration Exposure Facility begins (Forwarded)
               Re: Space Station Costs
----------------------------------------------------------------------

Date: 14 Feb 90 19:02:24 GMT
From: helios.ee.lbl.gov!pasteur!ic.Berkeley.EDU![e-mail]  (Eric T. Anderson)
Subject: Re: measurement standards (aerospace)


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

>...
>For shame! That's one of the few areas in which the "standard" system really
>shines, since it was a major design criterion. For instance, express 1/3
>of a foot in inches (4). Now try 1/3 of a meter in mm (333.33333333333...).
>As another example, the number of feet in a mile (5280) is evenly divisible
>by 2, 3, 4, 5, 6, 8, 10, 11, 12, 15, 16, 20, 22, 24, 30, 32, 33, 40, 44, 48,
>55, 60, 66, 80, 88, 96, 110, 120, 132, 160, 165, 176, 220, 240, 264, 330,
>352, 440, 480, 528, 660, 880, 1056, 1320, 1760, and 2640, a total of 46

Hey, let's just use base 12! or so!  Then we can divide by lots of
numbers...   We just need a lot more fingers.  =-)  How about it?

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

Date: 15 Feb 90 01:10:39 GMT
From: [e-mail]  (Bruce Lowerre)
Subject: Re: private spaceplane

In article <[e-mail]>, [e-mail] writes:
> In article <[e-mail]>, [e-mail] (Norman C. Kluksdahl) writes:
> >
> > Some of you may recall a discussion starting about a year ago
> > regarding private efforts to develop a small-scale shuttle/
> > spaceplane.  After some initial confusion, I ended up being the
> > designated coordinator of ideas, and began to have fun with the
> > idea of a garage-scale EAA-type spaceplane project.  At first, it
> > began as a 'Gedanken Experiment', merely a mental excercise to see
> > if such a project was within the realm of possibility.
>
> Sounds very interesting  -  as I'm not one of the ones who might remember this
> discussion from before, (surely I'm not the only one) maybe you could bring us
> up to date with your current state of thinking on this...

Does anyone remember Evel's attempted Snake River Canyon jump in a steam
powered rocket?  After that abortion, his next stunt was to be aboard the
first civilian rocket into space.  He hired an engineer, Truax (SP?) (sounds
like "true-ax"), to design and build a rocket that would get him into space.
Truax designed a rocket and made at least one test firing right here in
the East Bay.  It was not capable of orbiting and was more of a sounding
rocket where the passenger was just along for the ride.  The whole trip
would take less than 15 minutes but would reach an altitude of over 50
miles, high enough to qualify as an astronaut.

The plan started to fall apart when Evel encountered some difficulty with
a baseball bat.  Truax tried to continue by himself.  I don't what ever
finally happened; I don't think he could ever raise the money.  I know
that after Evel's troubles, Truax was eyeing up Jeanne Yeager as a
possible "pilot" because of her light weight.

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

Date: Tue, 13 Feb 90 19:46:50 EST
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: Re: Measurement standards


>From: voder!nsc![e-mail] (Amos Shapir)
>Subject: Re: measurement standards (aerospace)

>>As another example, the number of feet in a mile (5280) is evenly divisible
>>by 2, 3, 4, 5, 6, 8, 10, 11, 12, 15, 16, 20, 22, 24, 30, 32, 33, 40, 44, 48,
>>...
>That doesn't help much when I see a sign BUS STOP 400 FEET, and the mileage
>meter in my car is scaled to 1/10th of a mile!
>The problem with the imperial system is not subdivision, but consistency.

No argument (though almost all the mileage signs I see give distances in
tenths or quarters of a mile). I was refuting the claim that even divisibility
is an *advantage* of the metric system. The subdivisions in the "standard"
system were specifically designed to be easily divisible by low numbers, so
you are *more* likely to have fractional remainders using the metric system.
The inclusion of these factors is what makes "consistency" more difficult.
This is still a problem in the time base of SI, what with minutes, hours,
days, years, etc. You get around it by calculating everything in seconds,
then converting to the larger time units. Of course, everybody has calculators
and computers these days, so none of this is more than a nuisance.

>>Europe has been blocking an international standard on
>>HDTV television broadcast format unless it's PAL-compatible (or SECAM?) while
>>the US and Japan are willing to settle on an extension of NTSC.
>You'd understand why if you ever see a PAL transmission.  Compared to
>NTSC, it's crisp and crystal clear even in the present density.
>(And it's well known that NTSC stands for Never The Same Color :-))
Again, no argument about PAL picture quality. People I know who travel in
Europe say that the television there has beautiful sharp pictures - with an
annoying flicker, since they are 50Hz interlaced instead of 60Hz interlaced.
Apparently there is a fundamental limit in the ability of the human eye to
detect flicker in an image, and the lower limit of this is around 60Hz. (70Hz
would be better.) 50Hz is sufficiently slower that most people can detect
a flicker. (Europeans may have learned to ignore it.) Where the two frames
are different (i.e. near a horizontal line in the display) the resulting
30Hz flicker from NTSC is pretty bad - I suspect the 25Hz from PAL is worse.
You can get around this by using slower phosphors, but then motion is blurred.
(Advanced receivers use internal buffering to refresh both frames
simultaneously, at double the normal rate.) Advanced computer-driven displays
(such as the one proposed by Dale Amon for the space station) use tricks such
as separate RGB inputs, and extremely high pixel rates (many MHz).

Note: The potential resolution of NTSC broadcast is much higher than what is
available from current broadcasters - until recently, receiver quality has not
been good enough to justify a better effort. Some expensive receivers now use
advanced circuitry such as comb filters and tricks such as pixel averaging
to do the best they can with what is received. Also note that the HDTV format
currently in use in Japan is *not* a normal broadcast standard - it's more
analogous to cable.

>    Amos Shapir
>National Semiconductor, 2900 semiconductor Dr.
>Santa Clara, CA 95052-8090  Mailstop E-280
>[e-mail] or [e-mail]
                          John Roberts
                          [e-mail]

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

X-Delivery-Notice:  SMTP MAIL FROM does not correspond to sender.
Date: Wed, 14 Feb 90 19:28 GMT
From: RITA HAYWORTH <[e-mail]>

From:   [e-mail] (Jordi Iparraguirre)
Date:   Feb/14/1990
Subj:   HASA select & Operacio 9000


Help !
I m very interested on receivig NASA Select broadcastings.
It s said  that NASA Select TV satelite is geostationary over the USA,
but is there any other way for receiving their programs in Europe ?
Perhaps CCN broadcasts them too ? Are they received at Robledo de Chavela
(NASA tracking center near Madrid, Spain) station ? I will apreciate
very much any kind of information you can send me. Thanks in advance.



On the other hand, On Feb/18/1990 will begin in Catalonia (Europe)
OPERACIO 9000. In this operation, a man called Emili Reyes will be living
alone in a grot for 9000 days. He will be monitored by doctors, and his unique
link with the surface world will be a computer (Mac). Doctors want to study
human reactions in front the lonelyness, and among others, they will simulate
delay comunications as on a space trip to Mars.

It is not the 1st time that Emili Reyes goes in this bussiness. In 1970
he was underground for 1512 hours, and in 1973 he beat all records
staying alone for 2500 hours. Now he will try to be alone for 9000 hours
(375 days).

Jordi Iparraguirre.
  CS student at University Autonoma of Barcelona (Catalonia, Europe)
  [e-mail]
  [e-mail]

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

Date: 14 Feb 90 20:45:49 GMT
From: wuarchive!zaphod.mps.ohio-state.edu!usc!cs.utexas.edu!jarvis.csri.toronto.edu!utgpu!watserv1!watdragon!rose![e-mail]  (Shawn E. Koppenhoefer)
Subject: Re: Galileo Update - 02/12/90

In article <[e-mail]> [e-mail] (Bamf) writes:
>    Maybe I'm a bit early here, but what is the possibility of
>public access to the images returned by the craft, (at some later
>date, I figure)  Are they generally made available in some format,

Is there any way to get access to the RAW data or are we stuck
with only the 'results' of the imaging teams? (not that they don't do
a good job... )

~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~|       _ _       KLEIN BOTTLE for sale...
        Shawn E. Koppenhoefer |        |        enquire within.
 ...watmath!rose!sekoppenhoef |           -
~~~~~~~~~~~~~~~~~[e-mail] [e-mail]

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

Date: 13 Feb 90 20:51:10 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Close-up inspection of Long Duration Exposure Facility begins (Forwarded)

Mary Sandy
Headquarters, Washington, D.C.                  February 13, 1990

Jean Drummond Clough
Langley Research Center, Hampton, Va.

RELEASE:  90-23

CLOSE-UP INSPECTION OF LONG DURATION EXPOSURE FACILITY BEGINS


     NASA officials and principal scientific investigators making
their first close inspection of the Long Duration Exposure
Facility (LDEF) at Kennedy Space Center, Fla., report that the
spacecraft looks much like they expected and hoped for after its
extended stay in space.

     LDEF's 57 experiments provide a unique opportunity to study
significant long-term effects of spaceflight on a broad range of
materials and components, as well as on living organisms.  The
spacecraft was retrieved by the crew of Space Shuttle Columbia on
January 12.

     LDEF's exterior shows obvious effects from nearly 6-years'
exposure to bombardment by micrometeoroids and orbital debris,
atomic oxygen impingement and the Sun's ultraviolet rays.  LDEF
will provide unprecedented data on the changes caused by the
combination of these environmental parameters, because accurate
simulations of the complex space environment are difficult to
perform on Earth.  These and other effects will be evaluated in
detail once LDEF's experiments are removed for subsequent testing
and analysis.

     Discolorations or physical changes appear on many of LDEF's
thermal control and optical surface experiments.  There seems to
be a significant contrast between the surfaces on the leading
edge (facing the direction of flight) and those on the trailing
edge.  One major difference between these two sides of LDEF is
the high exposure to atomic oxygen on the leading edge and very
low exposure on the trailing edge.  Many of the materials appear
as expected for this extended exposure, while others look either
more or less degraded compared to preflight estimates.

     Observation of solar array and structural materials on
LDEF's leading edge and surrounding rows reveals that all
unprotected Kapton thin-film insulation appears to have eroded
away.  This Kapton erosion is responsible for the disappearance
of three solar cell modules and a number of 1-mil polymer film
materials on the Solar Array Materials Passive LDEF Experiment
(SAMPLE).  Kapton films protected with silicone coatings seem to
have survived prolonged exposure to atomic oxygen, however, along
with some silverized reflectors protected with ionic bonded
solids.  Researchers are somewhat surprised that observations
show white Tedlar is intact, and that Kevlar 29 and 49 appear
eroded, but whole.

     Two effects seen on SAMPLE and several other experiments are
not understood at this time.  Unbonded silvered teflon thermal
blankets appear white, while the silvered teflon bonded to
metallic substrates appears tarnished.  Elastomer materials,
typically used as seals, have greatly discolored.  Some surface
erosion occurred on the carbon fiber-epoxy matrix composite
materials.  Even though space debris impacts on the experiment's
solar cells appear to be numerous, few of the cells look broken.

     The Thermal Control Surfaces Experiment (TCSE) is a once-
active experiment that performed periodic in-space optical
properties measurements of exposed thermal control and optical
surfaces during LDEF's initial 15-18 months in space.  This
experiment will provide a record of the condition of the test
materials during that period, and postflight laboratory analysis
of the samples will determine any subsequent damage.  In
addition, the TCSE will be evaluated as a means to obtain
important knowledge on the effects of long-term space exposure on
complex optical, electronic and mechanical instrumentation.

     The Chemical and Isotopic Measurements of Micrometeoroids by
Secondary Ion Mass Spectrometry measured isotopic composition of
interplanetary dust.  A special capture cell on the front of LDEF
and two capture cells on the back collected vapor and debris
fragments from impacts.  When particles penetrated the foils,
they should have "exploded" on hitting the plates beneath,
producing a plume of vapor and debris that would redeposit on the
underside of the plastic.

     Unfortunately, many capture cells suffered catastrophic
rupture of the thin entrance plastic films during LDEF's longer-
than-planned sojourn in space.  But if the plastic was in place
when impacts occurred, there should be a spray of vapor and
debris on the germanium plates that can be analyzed.  The initial
look from about six feet away shows at least half of the front-
facing cells have visible impacts; at the microscopic level there
probably will be many more.  The knowledge gained from LDEF will
be used to design a more complex interplanetary dust experiment,
one that will differentiate between dust from comets and
asteroids, for Space Station Freedom.

     The Heavy Ions in Space (HIIS) experiment used plastic track
detectors to measure the abundance of chemical elements in cosmic
radiation.  The experiment should offer new insights into the
origin of chemical elements and may show how the elemental
composition of the Solar System differs from that of the rest of
the galaxy.  The data also will improve our knowledge of
radiation hazards faced by astronauts and by modern micro-
electronic components in space.

     On seven of the eight HIIS modules, multilayer insulation
thermal blankets partially detached and rolled up while LDEF was
in orbit.  The loss of temperature control and exposure of some
of the detector material to direct sunlight probably resulted in
some data loss.  The thermal blanket on the eighth HIIS module is
largely intact and may have preserved the data in that module.

     Still another experiment, Space Exposed Experiment Developed
for Students (SEEDS), looks good and all hardware is intact on
the tray, suggesting that the seeds have been protected as
planned.  After preliminary growth tests, the 12.5 million tomato
seeds that flew aboard LDEF will be distributed to U.S. students
in grades 5 through university for use in classroom research.

     Experiment trays will be removed from LDEF around February
22 and delivered to the principal investigators.  By the end of
April, all experiments should be in the hands of the
investigators and analyses of the experiments underway.

     Results from the LDEF mission will furnish invaluable data
for design of future space structures, such as Space Station
Freedom, as well as insight into Earth's cosmic origins.

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

Date: Wed, 14 Feb 90 13:09:37 PST
From: mordor!lll-tis!ames!ucsd!pnet01.cts.com![e-mail] (Jim Bowery)
To: crash![e-mail]
Subject: Re: Space Station Costs

Henry Spencer writes:
>                                     .....  It's not likely that it will
>get a chance unless it is rammed down NASA's throat by higher management.
>Just going ahead and *doing the job*, forgetting all the crap about new
>technology and advanced robotics and 57 unmanned preliminary missions,
>may sound attractive to space enthusiasts, but the reaction from the NASA
>facilities and contractors -- who together have a lot of political clout --
>will be basically "sounds like less money for us -- we're against it".

You bought the Big Lie, Henry.

This is exactly the Big Lie that the NASA facilities and contractors
want you to believe because they know if space enthusiasts ever wake
up to the true level influence we have over the Spacefare Pogrom
it's all over.  It is therefore exceedingly urgent for them to
have the leadership of organizations like National Space Society and
others, such as yourself, repeatedly convey the message that the civil
servants and contractors somehow, magically, have Congress by the ****s
to a point that grassroots input can't win.  Only in this way can they
discourage us so that we never even TRY to get a taste of our precious
constitutional power as congressional constituents, and keep us believing
that we must suck up to these ignoble groups as "The Only Game In Town".

That this is a Big Lie is obvious when one considers the fact that the
environmental movement successfully overcame far greater odds when they
fought polluting industries that didn't even depend on Congress
for their funding.  With the Spacefare Pogrom depending entirely on
Congress for its funding, if the grassroots enthusiasts start calling
for reform, all these "Big Powerful Interests" can do is simply roll over
and play dead -- or start acting like reform was Their Idea All Along
(which is closer to what is actually happening now as a result of HR2674).

Don't let them discourage you!
---
Typical RESEARCH grant:
$
Typical DEVELOPMENT contract:
$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

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

End of SPACE Digest V11 #42
*******************