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Subject: SPACE Digest V10 #169

SPACE Digest                                     Volume 10 : Issue 169

Today's Topics:
        Re: Alledged Catholic Anti-Technology
        Re: Galileo Spun/Despun section communications
          Re: prevention of asteroid impacts
           Re: Try thinking before stinking
                 Re: finally!
                Neptune update
              Re: Galileo Update
Re: NASA seeks Space Station Assured Crew Return Vehicle proposals (Forwarded)
          Pu in Environment and Effects: Correction
         Electronics and Microphones in >20kHz range
               Re: Pharmacies in Space
----------------------------------------------------------------------

Date: 20 Oct 89 16:57:02 GMT
From: bfmny0![e-mail]  (Tom Neff)
Subject: Re: Alledged Catholic Anti-Technology

Discussion of the Church vs technology should be moved to one of the
talk, politics or religion newsgroups -- it ain't space.  Thanks.

--
"UNIX should be used          ::   Tom Neff <[e-mail]> or
 as an adjective." -- AT&T   ::    ...uunet!bfmny0!tneff (UUCP only)

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

Date: 20 Oct 89 15:46:11 GMT
From: jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Galileo Spun/Despun section communications

In article <[e-mail]> [e-mail] (Loren (Buck) Buchanan) writes:
>The question I have is how does the Despun section (the part with most
>of the instruments) communicate with the Spun section (the part with
>the main antenna and most of the computers)?

The usual sorts of methods:  slip rings and rotating transformers.  The
latter may not be entirely obvious:  the two halves of a transformer don't
*have* to be in mechanical contact, and with suitable design there can be
a small air gap and the two halves can rotate with respect to each other.

If it were being built with modern technology (remember how old much of
that hardware is), it would probably use optical transmission for data.
--
A bit of tolerance is worth a  |     Henry Spencer at U of Toronto Zoology
megabyte of flaming.           | uunet!attcan!utzoo!henry [e-mail]

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

Date: 20 Oct 89 06:45:49 GMT
From: bungia!orbit!pnet51![e-mail]  (S Schaper)
Subject: Re: prevention of asteroid impacts

Yes, I was thinking of many boosters so that there would be multiple devices
to use at the target, both US and CPSU.
  But there must be something wrong with that, too.

UUCP: {amdahl!bungia, uunet!rosevax, chinet, killer}!orbit!pnet51!schaper
ARPA: crash!orbit!pnet51![e-mail]
INET: [e-mail]

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

Date: 20 Oct 89 16:21:48 GMT
From: oliveb!mipos3!td2cad![e-mail]  (John Reece )
Subject: Re: Try thinking before stinking

In article <[e-mail]> [e-mail] (David Smith) writes:
>Ah, yes, the olden days were so golden.  So the Atlas program's performance
>record gleams when compared to the Shuttle?  Are you saying that of the
>first 30 Atlas launches, fewer than one failed?  Or are you claiming that
>Atlas has not failed since Shuttle did?  If the Shuttle program had been
>terminated after 13 successful flights, with the orbiters consigned to
>museums, would it have been as successful and reliable a launcher as the
>Saturn V?


Let's also remember that one Titan II during the Gemini program shut
itself down at about T - 1.  Two seconds later, and two Gemini
astronauts would have been history.



--

John Reece
[e-mail]

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

Date: 19 Oct 89 20:27:09 GMT
From: portal!cup.portal.com![e-mail]  (Laurence Larry Sheldon)
Subject: Re: finally!

That the shuttle and galileo are on their way is good news, indeed.

(That _does_ mean all the rants and screeds about and by the techniphobes
will stop, does it not?)

Oh.  Sh*t!  Well.   Is there a news-group here where I can find out
about real-world stuff, status reports, and plans?

I can't read shuttle status here because the brain-damaged reader on this
service lumpw them under a "thread" that started back in August, and
now contains far too many Chrisitc fits to be worth wading through, even
for deseirable material such as shuttle status.

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

Date: Fri, 20 Oct 89 11:36:07 PDT
From: Peter Scott <[e-mail]>
Subject: Neptune update

Extracted from NASA's _Voyager Bulletin_, Mission Status Report No. 96,
October 4:

NEPTUNIAN METEOROLOGY

[...]

Although Neptune receives only 1/900th as much energy from the Sun as the Earth
does, it reemits about three times this amount - an indication that heat is
being generated in Neptune's interior and radiated to space.  Scientists have
long thought that the winds in a planet's cloud tops are driven by the Sun's
heat, but now they must consider more strongly the contributions of the planet's
own interior heat source.

Voyager's infrared observations of Neptune showed that temperatures are
warmer near the equator and south pole, and cooler in mid-lattitudes -
surprisingly similar to the case at Uranus.  Since the south pole is tilted
slightly toward the Sun at this point in Neptune's orbit, it is not
surprising that it is warm.  But the warmth at the equator is surprising
because less sunlight falls there due to the planet's tilt.  Voyager's
ultraviolet investigation measured temperatures at high altitudes in Neptune's
stratosphere at about 400 kelvins (250 deg F), while the infrared investigation
measured the temperature at the 100 millibar pressure level to be about 55 K
(-360 F).

While analysis continues, the results of the radio science investigation seen
consistent with an atmospheric chemical composition of about 85 percent
molecular hydrogen, 13 percent helium, and 2 percent methane.  The infrared
investigation's results indicate that some amount of acetylene exists as well.
[God help any astronaut who leaks any oxygen into that stuff - PJS]

[...]

The Great Dark Spot, at about 22 degrees south latitude, is probably at
lower altitude than its accompanying bright clouds.  The size of the [GDS]
in its east-west extent is comparable to the diameter of the Earth - over
12,500 km (nearly 8,000 mi).  Time-lapsed movies constructed from single
frames show that the [GDS] is not totally oval, has spiral arms, and appears
to have a counterclockwise circulation pattern.  Imaging scientist Dr. Andy
Ingersoll of Caltech drew chuckles with the remark that the [GDS] looks
like "a great glob of pizza dough going around".  The [GDS] circles Neptune
in a little less than 18 hours, implying that it is in an atmospheric
zone with westward (retrograde) winds of more than 300 meters per second
(700 mph!).  Bright, wispy, "cirrus-type" clouds overlie the [GDS] at its
southern and northeastern boundaries.

According to atmospheric scientist Dr. Jim Pollack of NASA's Ames Research
Center, some of the bright spots on Neptune may be convective clouds rising
above the base of the methane clouds.  He suggests a cycle of methane on
Neptune wherein ultraviolet sunlight first converts methane to hydrocarbons
in the stratosphere.  The major hydrocarbons, such as ethane and acetylene
then drift down to the colder lower stratosphere, where they evaporate and
condense into hydrocarbon ices.  These ice particles fall into the warm
troposphere, evaporate, and are converted back to methane.  The methane is
returned to the stratosphere by buoyant convective clouds, which rise to the
base of the stratosphere or higher.  The bright central core of the
southern dark spot is probably such a rising convective cloud, and the bright
cloud at about 42 degrees south latitude may be interpreted as a cloud plume
rising between the methane and hydrogen sulfide cloud decks.

As Voyager 2 approached the planet, imaging scientists were able to track the
features in the clouds to determine the wind speeds.  They were surprised
to find that some features, such as the [GDS], had a rotation period of 18
hours, in close agreement with ground-based observations, but that other
features moved much faster.  The bright cloud at about 42 degrees south
latitude was nicknamed "Scooter" because of its 16-hour rotation period.
However, motions in the atmosphere are indicative only of wind speeds.  The
rotation of the bulk of the planet can best be measured by studying the
periodicity of the planet's radio signals, generated by deep-seated convection
currents in the planet's interior, and carried to space along the planet's
magnetic field lines.  The Planetary Radio Astronomy Team [PRAT?], led by
Dr. Jim Warwick of Radiophysics, Inc., determined from Neptune's radio signals
that a Neptunian day is 16 hours 3 minutes.

Dr. Brad Smith, leader of Voyager's Imaging Science Team, suggests that the
clouds near the [GDS] are not moving rapidly themselves, but that the air
around them is, analogous to lenticular clouds that form over mountains here
on Earth.  As winds go through the region, they are deflected upward where
the volatiles condense out and form clouds.

Voyager also saw cloud shadows in Neptune's south polar region, the first time
a Voyager spacecraft has been able to see any such features on a planet.  The
shadows are cast by methane cirrus-type clouds that are estimated to be 50 to
75 km (30 to 45 mi) above the haze or stratus clouds.


Peter Scott ([e-mail])

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

Date: 20 Oct 89 19:30:27 GMT
From: jarthur![e-mail]  (Mark Wilkins)
Subject: Re: Galileo Update

In article <[e-mail]> [e-mail] (Scott Pinkerton) writes:
>In article <[e-mail]> [e-mail] (Ron Baalke) writes:

>>2.9 revolutions/second for the separation of the IUS from Galilio sooned
>>followed.
>
>Was this correctly printed ??  The IUS spun itself and the payload up to
>174 RPM prior to separation ??  That seems like an incredible controls
>problem to prevent the stack from spinning in a very wide "cone".  Also at
>actual separation, the CG will jump back some 30-40 feet maybe (don't know
>actual Galileo dimensions) - again sounds like one hell of a controls
>problem.  Was this meant to be 2.9 RPMinutes ??

   Sometime if you ever get the chance watch some of the footage of one of
those satellites with an IUS being launched.  When STS-26 went up many at
our school watched the TDRS deployment and the thing was rotating
about one or two times each second during the deployment from the cargo
bay.  Galileo is (I think) smaller than TDRS and I would not be surprised at
2.9 revolutions per second, especially after the IUS has carried the thing
some distance from the shuttle.

       -- Mark Wilkins

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

Date: 20 Oct 89 17:18:15 GMT
From: stsci![e-mail]  (Giggles Gonzaga -- Prophetess of Wisdom and Truth)
Subject: Re: NASA seeks Space Station Assured Crew Return Vehicle proposals (Forwarded)

From article <[e-mail]>, by [e-mail] (Peter E. Yee):
> Headquarters, Washington, D.C.                    October 3, 1989
>
> NASA SEEKS SPACE STATION ASSURED CREW RETURN VEHICLE PROPOSALS
>
>      NASA today released a request for proposals (RFP) for
> definition studies of a new vehicle that would serve as a
> lifeboat for Space Station Freedom, providing the capability for
> assured crew return from space.  Deadline for proposal submission
> is Nov. 16, 1989.

Here's something I don't understand -- the release is dated Oct 3 1989. The
deadline for proposal submission is Nov 16 1989. That's not a whole lot of
time. Somebody please educate me ... have sub-contractors been secretly working
on this vehicle? Even if it is for a preliminary study, 1.5 months is very
short notice!

Thanks,
    Shireen

--
______________________________________________________________________________
Shireen Gonzaga/Space Telescope Science Inst./3700 San Martin Dr., Baltimore,
MD21218/tel[phone]/ARPA [e-mail]/SPAN SCIVAX::GONZAGA/ "which
planet is the Hubble Space Telescope going to?" -- question from you-know-who ...

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

Date: 20 Oct 89 17:19:11 GMT
From: jumbo![e-mail]  (Bob Ayers)
Subject: Pu in Environment and Effects: Correction

[e-mail] (John Sahr) and [e-mail]
(RAMontante) quote my remark

    We (the USA and the USSR) have atomized hundreds of kilograms of Pu in
    the atmosphere, creating maximally-dispersed Pu and daughter products.
    Nothing much happened. Statistical studies have usually shown no
    increase (above background) in *anything*.

and supplies a number of references describing quite-noticable physical
changes.

Sorry.  I mis-spoke.  I should have said

    We (the USA and the USSR) have atomized hundreds of kilograms of Pu in
    the atmosphere, creating maximally-dispersed Pu and daughter products.
    Nothing much happened. Statistical studies have usually shown no
    detectable increase (above background) in *any* human ailment.

John also adds Chernobyl and the Soviet satellite-reactor that hit Canada
to the list of man's contributions to radioactivity in the environment.
All true. And yet they too didn't cause great harm. The last I read about
Chernobyl ina  reputable publication (i.e. Science), the feeling was that,
except in the immediate vicinity, the medical effects (increased cancer
incidence etc) of the radioactivity would not be statistically discernable
in the European population.

Bob

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

Date: 20 Oct 89 14:31:45 GMT
From: cbmvax!vu-vlsi!swatsun![e-mail]  (Leif Kirschenbaum)
Subject: Electronics and Microphones in >20kHz range

Hello, I'm sorry to have to post this here, but I thought that with the
number of people involved in reseacrh someone might have an answer.

I'm looking for a source of microphones with a response in ranges over
20kHz (above audio) preferable up to 100-200kHz.  I'm planning to build
a heterodyner to transfer ultrasonics down to audio, but need a microphone
that'll pick it up.  None of the electronics catalogs seem to have it.

Please e-mail me direct if anyone has any information as school closes
for the next week and I won't be reading Usenet.
Thanks very much in advance.

--
Leif Kirschenbaum '91            Chemical Physics Major
Swarthmore College            "How does that work?" [in a math class]
UUCP:  rutgers!bpa!swatsun!leif        "It's the *magic* of complex analysis."
CSnet: [e-mail]    Bitnet: [e-mail]
--
Leif Kirschenbaum '91            Chemical Physics Major
Swarthmore College            "How does that work?" [in a math class]
UUCP:  rutgers!bpa!swatsun!leif        "It's the *magic* of complex analysis."
CSnet: [e-mail]    Bitnet: [e-mail]

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

Date: 20 Oct 89 17:35:10 GMT
From: telesoft![e-mail]  (David Reisner)
Subject: Re: Pharmacies in Space

In article <[e-mail]>, [e-mail] (Roger Arnold @prodigal) writes:
> [e-mail] (Paul Dietz) writes:
> > [..]
> > McDonnell-Douglas had a project -- continuous
> > flow electrophoresis -- that was obsoleted by advances in earth-based
> > protein separation technology.  McDD terminated CFE last year.
> > [..]
>
> Whoa, there!  CFE was terminated, true, and it's also true that for
> specific compounds, alternative separation methods have been found
> that don't require microgravity.  But the alternative methods are not
> as direct as CFE, and, as I understand it, require some pretty fancy
> molecular engineering that has to be invented for each new compound.
>
> It's a little unfair to say that CFE has been obsoleted.

The CFE equipment is still around.  The equipment required substantial
update (probably due to some of the earth-based advances), and Douglas
didn't want to spend the money.  They gave the whole thing to NASA, who
might well fly it if they ever do update it.

-David

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

End of SPACE Digest V10 #169
*******************