Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V12_6/V12_680.TXT

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Subject: SPACE Digest V12 #680

SPACE Digest                                     Volume 12 : Issue 680

Today's Topics:
    Re: Japanese "cosmoreporter" begins broadcasts from USSR's Mir
              LLNL vrs. Freedom flamewar
              Galileo Update - 12/11/90
           Re: space news from Nov 12 AW&ST
             Re: A human being in vacuum
             Re: A human being in vacuum
               Magellan article
             Holes,station,vulcan
     STS-35 postflight crew press conference (Forwarded)

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription notices,
  should be sent to [e-mail], or, if urgent, to
             [e-mail]

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

Date: 11 Dec 90 16:16:00 GMT
From: censun1!lescsse![e-mail]  (Gary A. Morris)
Subject: Re: Japanese "cosmoreporter" begins broadcasts from USSR's Mir

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


>     On board the Mir space station ...

>Two experiments will be performed.  The
>first is transmission of amateur radio and TV signals to Ham radio groups
>in Japan.  That may have been the equipment that was tried when Mir and the
>shuttle were within 65 Km (40 mi) of each other on Dec. 4th.  Unfortunately
>they could not communicate - someone had an antenna pointed in the wrong
>direction (the report did not say whom).

There was no attempted amateur radio contact with the Mir on Dec 4th,
the Soviets said they would be too busy with docking and unloading to
schedule a contact.

Perhaps Musa was trying anyway, unfortunately Ron was not operating
at the time.  If so they may have assumed an antenna pointing problem.

There was a contact scheduled for the next close conjunction which would
have occurred today (Tues 12/11/90) but since they landed last night,
that won't take place :-(

--GaryM
--
Gary Morris                    Internet: lobster!lescsse![e-mail]
Lockheed (LESC), A22           UUCP:     lobster!lescsse!gamorris
Space Station Freedom          NASAmail: gmorris/jsc/nasa
Houston, Texas                 Internet: [e-mail]

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

Date: 11 Dec 90 21:05:03 GMT
From: swrinde!zaphod.mps.ohio-state.edu!sdd.hp.com!news.cs.indiana.edu!msi.umn.edu!cs.umn.edu!kksys!orbit!pnet51![e-mail]  (S Schaper)
Subject: LLNL vrs. Freedom flamewar

I have much enjoyed these postings, but please, keep out the flames?
  I would much like to see each of you post the current specifications for the
proposed stations. LLNL in detail sufficient for us to visualize it as well as
understand its' capabilities, and likewise for the current revision of
Freedom.
   Thank you.

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

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

Date: 12 Dec 90 01:24:45 GMT
From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Galileo Update - 12/11/90


                        GALILEO STATUS REPORT
                          December 11, 1990

     Yesterday, the Galileo spacecraft successfully completed a SITURN to
lead the sun, and the RPM (Retro Propulsion Module) thruster maintenance
activity and enabling of Sun Gate fault protection.

     Today, the spacecraft successfully completed the Target Motion
Compensation (TMC) activity associated with the remote science pointing
platform.  Earth spin movie photographs are presently in process.  About
1500 of the planned 1630 remaining photographs will be taken for the spin
movie as Galileo recedes from Earth.  The majority of science instruments
continue to collect valuable Earth encounter data.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

Date: 12 Dec 90 15:02:11 GMT
From: eagle![e-mail]  (Ronald E. Graham)
Subject: Re: space news from Nov 12 AW&ST

In article <[e-mail]>,
     [e-mail] (Henry Spencer) writes...

Regarding Fred...

>Speaking of which...  Redesign work has been underway quietly for some time,
>but now it is out in the open.  The long truss is probably not long for this
>world, in particular:  a Goddard project to attach science payloads to it
>has been cancelled, and the request for bids for the assembly training
>facility in Houston has been withdrawn.  The leading idea right now is
>simply to retain the central cluster of modules, but kill the truss.
>Among other advantages, the resulting station should have gravity-gradient
>stability, eliminating attitude-control thruster firings that eat fuel and
>bother the microgravity people.

Gravity-gradient stability may not necessarily mean that all attitude control
firings are eliminated (although I'm not sure whether that's what the article
intended to say).  Although a body will tend to stay in a gravity-gradient
stable position once that position is reached, aero forces could perturb the
body.  If Fred retains solar arrays, those guys will have to be pointed, and
that would cause your aero to vary during the orbit.  That being the case,
you'd need your control-moment gyros to trim Fred, and you may need a firing
from time to time to "dump" the gyros.

The article didn't say anything about Fred's photovoltaic arrays, but we
have been hearing that *that* part of the design will most likely not be
changed much - only where they get positioned would get changed, and how
many there would be, since "Assembly Complete" is now a wild dream.

Anyway, under those conditions, although you could reduce your firings, you
can't get rid of 'em altogether.  Looks like the reaction control system
would certainly be sized down, at least.

RG

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

Date: 12 Dec 90 20:55:52 GMT
From: ogicse!unicorn![e-mail]  (james d. Del Vecchio)
Subject: Re: A human being in vacuum

Followups To: sci.space

Someone posted that vacuum was an isulator.

    [e-mail] (Douglas S. Rand) writes:

>Radiational cooling is pretty effective,  especially when
>the surrounding black body temperature is 3 or 4 degrees K.  If the
>person in the vacuum is in shadow they could probably freeze in just
>a few minutes.  If they're in direct sunlight then they might boil on
>one side and freeze on the other (lots of fun).
        --------
I don't have a clear idea of how that would work.  If the heat in your
body isn't going _into_ something (like air), then where is it going?

I don't understand the "3 or 4 degree K" outside temp.  How can it have
a tempature if there's nothing there?   Do you just mean an imperfect vacuum
where the particles hitting you are at 3-4 deg K?
I always had the idea that something being cold was only relavent if it was
actualy touching you.  What's touching you in space?

        Jim Del Vecchio

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

Date: 12 Dec 90 22:32:04 GMT
From: agate!linus!linus!mir![e-mail]  (Douglas S. Rand)
Subject: Re: A human being in vacuum

In article <[e-mail]>, [e-mail] (james d. Del Vecchio) writes:
> Followups To: sci.space
>
> Someone posted that vacuum was an isulator.
>
>     [e-mail] (Douglas S. Rand) writes:
>
> >Radiational cooling is pretty effective,  especially when
> >the surrounding black body temperature is 3 or 4 degrees K.  If the
> >person in the vacuum is in shadow they could probably freeze in just
> >a few minutes.  If they're in direct sunlight then they might boil on
> >one side and freeze on the other (lots of fun).
>         --------
> I don't have a clear idea of how that would work.  If the heat in your
> body isn't going _into_ something (like air), then where is it going?
>
> I don't understand the "3 or 4 degree K" outside temp.  How can it have
> a tempature if there's nothing there?   Do you just mean an imperfect vacuum
> where the particles hitting you are at 3-4 deg K?
> I always had the idea that something being cold was only relavent if it was
> actualy touching you.  What's touching you in space?
>
>         Jim Del Vecchio

No.  The meaning of all this is that objects lose and gain heat through
two basic mechanisms (not including other physical alterations like
kinetic changes, chemical reactions, etc.). The first is conduction.
In conduction the object is in contact with another object at a different
temperature and the result  is that over time the hotter object becomes
cooler and the cooler object becomes warmer.  This is the most familiar
mechanism to most people.  But this is only one of the mechanisms where
an object loses or gains heat.

The other mechanism for changing an otherwise inert object's temperature
is through radiation.  The easiest example is the warmth you feel in front
of a fireplace or bonfire,  or the heat on your skin on a sunny day.  This
is heating through radiation.  If you place a piece of cardboard between
your face and the fire you'll suddenly feel much cooler.

In radiational heating you are absorbing energy from infared radiation which
warms you.

Now if you put something in a vacuum it will only be heated through radiation.
But,  in addition to absorbing radiation the object will also produce radiation!
This produced radiation is in proportion to things like the surface area and
temperature of the object.  If one is in deep space and not being radiated by
some large hot object (like the sun) then one is effectively not being warmed
at all.

The 3->4 degrees Kelvin figure is about the temperature being (or not being)
radiated by 'space'.  That is an object left indefinitely in deep space would
eventually equilibrate at 3->4 degrees K.  So the human in space will radiate
quite alot of energy at ~300 K but absorb almost no energy in return.

You can get a really disgusting description of the whole mess in a physics
text like Resnick and Haliday or Sears and Zymanski.  I actually once had
a long argument with a couple of fellow students as an undergraduate where
they were arguing that everything is heated by conduction.  To this day
I'm not sure how far my leg was being pulled (this was at an engineering
school, after all).

--
Douglas S. Rand
Internet:   <[e-mail]>
Snail:        MITRE, Burlington Road, Bedford, MA
Disclaimer: MITRE might agree with me - then again...
Amateur Radio: KC1KJ

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

Date: 13 Dec 90 22:39:16 GMT
From: swrinde!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Magellan article

Associated Press -- 12/12/90
"Venus Magellan"

"An alignment of the planets will interfere with the Magellan
spacecraft's ability to send pictures of Venus back to Earth for
the next six weeks beginning Sunday, NASA says."

The AP reports that in late October and early November the
sun was between Venus and Earth, forcing a two-week halt to
Magellan's $744 million mission to use radar to map the
surface of cloud-shrouded Venus.

Now, the AP says, it is the planet Venus itself which is getting
in the way, although the mapping mission will continue.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

Date:         Thu, 13 Dec 90 17:58:23 EST
From: Tommy Mac <[e-mail]>
Subject:      Holes,station,vulcan

Hey folks!  I just jumped on this listserv (Like it a lot, too), and it looks
like I'm getting about a weeks delay in recieving things.  I don't know if this
is true for the rest of you, so if it seems like I'm out in the dark on some of
these topics, that's why:

Re; Vulcan.  It seems that I remember "Vulcan", as a planet name was first used
for the planet that some believed held the same orbit as Earth, but at constant
conjunction with Sol (other side).  Does this sound familiar?  I think they
dropped this idea quite a while ago.

Re; Black Holes
Ray, remember your four forces.  Star happen because of gravity defeating
the weak force (I think), as do white dwarves and nuetron stars.  Black
holes happen when gravity defeats the strong force (this is the strongest
of the four).  The reason they are black is because light doesn't move faster
than their escape velocity, so no matter how 'unstable' it might become, it
could not explode, if you define exploding as matter being thrown from it.  If
light doesn't move fast enough to escape, how could matter?  The structure of a
black hole is totally unknown because we simply can't see it.  The best images
we have of black holes are based on the assumption that they are compressed by
gravity until not even nuetrons hold up to the pressure.  This kind of force
would certainly create stability, as nothing can move.  Although, spinning
holes could be another story...

Re; Politicians in space.
I have no idea what the record or beleifs of "barfin" are, but; Every naut
(astro and cosmo) has returned with new impressions of earth, usually focussing
on 'oneness' with others, fragility of the biosphere, lack of natioanal borders
and other similar visions.  Maybe we should send all politicians into space, or
have all the arms talks there.  Maybe we'd get some long-range policy enacted
by this frustrating and petty group.


Re; space stations

When the polynesians (sp?) left on their sea voyages for the islands of the
pacific, they certainly did not plan to return, so they did not build ports.
likewise, all the people who have created successful 'deep space' missions
did not include a space stations (viking, mariner, galilieo, voyager, etc), for
what I think are obvious reasons.
The moon mission was a few shot, exploratory/show-off mission, not a trip
with long-range planning in mind.  I'm quite certain that Magellan and
Columbus did not start buying property at every place they landed with the
intention of building ports (wasn't cost-effective).
However, if we want a permanent place in space, a space "station" is very
necessary.   Why?

-Space in space.  GEO is a very popular place (all of you watching Satcom for
NASA broadcasts know that).  With space stations, the density of GEO vehicles
can be increased, allowing greater use of this position

- Storage.  Currently, the ETs from the Shuttle are dropped into the Indian
ocean, at a net payload loss, because of lack of something to do with them
in space.  A station would allow their storage for future use, as well as the
fuel that is left in them after a boost.

-  Industrial processing.  Any industrial processing in space (not glass beads
and crystals, I'm talking energy and raw materials) will require a lot of
equipment.  Put it all in one place, add some docking ports and habitats, and
you've got a station.  Why not send up the parts we can use now with this end
in mind?  If you don't want to live or create in space, then why do you read
this stuff?

- Use of cis-lunar space.  Of course, the best place for this kind of station
would be on the moon.  Does that make it a 'planet-station'?


----Build a PRACTICAL (i.e. designed with long-range goals) space station, and
let the space age begin

           -If God had wanted us to travel in space, he would have given us a
            large moon full of metal oxides (applies to viewing the corona too)

Tommy Mac
Acknowledge-To: <18084TM@MSU>

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

Date: 12 Dec 90 21:16:17 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: STS-35 postflight crew press conference (Forwarded)

Mark Hess/Ed Campion
Headquarters, Washington, D.C.                  December 12, 1990
(Phone:  [phone])

Barbara Schwartz
Johnson Space Center, Houston
(Phone:  [phone])


EDITORS NOTE N90-101:  STS-35 POSTFLIGHT CREW PRESS CONFERENCE


     The STS-35 Crew Postflight Press Conference will be held at
the Johnson Space Center, Houston, Building 2, Room 135, on
Thursday, Dec. 20, at 2 p.m. EST.  Crew members will narrate
slides and film from their recent Astro-1 mission, followed by a
question and answer session.

     News media are invited to participate at JSC or by two-way
audio from NASA Headquarters, Washington, D.C., and other
participating NASA facilities.

     The briefing will be carried live on NASA Select television,
Satcom F2R, Transponder 13, C-band, at 72 degrees West Longitude,
Frequency 3960.0 MHz, Audio 6.8 MHz.

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

End of SPACE Digest V12 #680
*******************