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Subject: SPACE Digest V13 #629

SPACE Digest                                     Volume 13 : Issue 629

Today's Topics:
       Re: Request For Discussion: sci.space.moderated
          Astro mission to refly (Forwarded)
            Budget Numbers Wanted
           Re: Rational next station design process
          Re: space news from March 18 AW&ST
          Re: What comes after Fred's death?
  Re: Desaturation of the Reaction wheels on the Magellan Spacecraft
     Re: Gravity waves (was Re: LIGO (was Re: IT'S OVER))
           Re: Rational next station design process

Administrivia:

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

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

Date: 20 May 91 16:28:33 GMT
From: gauss.rutgers.edu!math.rutgers.edu![e-mail]  (Scott Cromar)
Subject: Re: Request For Discussion: sci.space.moderated

In article <[e-mail]> [e-mail] (Michael Woodhams) writes:

> I suggest that the moderator accept submissions that
> (1) contain new factual information regarding space science and
> technology.

> (2) add substantial new ideas to an existing discussion, from people
> with experience in the field or with supporting references.

> (Anyone suggest more criteria?)

This is probably included under heading #1, but I would like to see
the solar flare reports in any such moderated group.  They are one of
the few things that keeps me subscribed to this group.
--
--Scott Cromar *Support S 3 and HR 1177 (The Clean and Fair Election Act)

"Anything we do is in our national security interest."
--Ronald Reagan to reporters 16 July 1986

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

Date: 20 May 91 17:19:40 GMT
From: [e-mail]  (Peter E. Yee)
Subject: Astro mission to refly (Forwarded)

Paula Cleggett-Haleim                                          May 20, 1991
Headquarters, Washington, D.C.
(Phone:  [phone])


RELEASE:  91-76

ASTRO MISSION TO REFLY

    NASA today announced that the second Astro mission will fly
aboard the Space Shuttle.  "We are delighted to be able to refly this
proven scientific performer," said Dr.  Lennard A. Fisk, Associate
Administrator for Space Science and Applications.

    The success of the earlier mission and the demonstrated ability
of the instruments to acquire high-quality scientific data are among
the major reasons for reflight of the Astro payload.

    Astro-2, like Astro-1 which flew in December of 1990 aboard Space
Shuttle Columbia, will be dedicated to a single scientific discipline -
astrophysics.  The following three instruments will fly on Astro-2 and
observe energetic objects in space in the ultraviolet portion of the
electromagnetic spectrum:

    o      The Hopkins Ultraviolet Telescope  (HUT), developed at
    Johns Hopkins University, performs spectroscopy, breaking light
    into its constituent colors, allowing scientists to analyze the
    chemical composition and temperature of the objects HUT    observes.

    o      The Ultraviolet Imaging Telescope (UIT), developed by
    NASA's Goddard Space Flight Center, produces images of especially
    hot components of nebulae, stars and galaxies. These images
    help to explain the physical structure of such objects.

    o  The Wisconsin Ultraviolet Photopolarimeter Experiment
    (WUPPE), developed at the University of Wisconsin, measures
    a subtle characteristic of light, its polarization.  These
    measurements probe the orientation and detailed physics of the
    distant regions in which the light originates.

    Astro-2 complements the much larger Hubble Space Telescope.  HUT,
for example, explores a region of the spectrum immediately adjacent to
that studied by Hubble.  UIT, because of its very large field of view,
can serve as a "finder" for the powerful imaging devices aboard
Hubble.  Finally, WUPPE's precision polarimetry adds another dimension
to the physical understanding of astronomical objects obtained from
Hubble's collection of instruments.

    During the Astro-1 mission, new results were obtained at wavelengths
observable only from space.  Astronomers gained insights into the
properties of diffuse dust found between stars as well as details of
the formation of new stars in distant galaxies.  They also learned that
the predicted decay of certain sub-atomic interstellar particles did
not occur, at least not at the expected level.

    Dr. David Huenemoerder, Program Scientist on Astro-1, said, "The
Astro Principal Investigators and their teams will be very pleased.
That first flight was just a taste of the scientific insights they
expect to emerge from Astro-2."

    Astro-2 will be managed by the Marshall Space Flight Center,
Huntsville, Ala., for the Office of Space Science and Applications,
NASA Headquarters, Washington, D.C.

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

Date: 20 May 91 23:54:53 GMT
From: [e-mail]  (William Dow Rieder)
Subject: Budget Numbers Wanted

With all the smoke and flames about the Freedom cancellation, I think
it would be useful if some kind, informed soul could post some of the
relevant numbers - specifically:
*Original NASA budget - what the President asked for.
    (with breakdowns by category/progect)
*Original HUD/whatever budget - other programs funded from the same pot.
Current figures for both after the cuts - with breakdowns.
Last years' numbers for both.
    This would help give more substance to the debate, I believe.
Anyone have the info? (Allen?)   Thanks in advance.

                    W. Dow Rieder

     When the only tool you have is a hammer, all your problems
start to look like nails...

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

Date: 22 May 91 16:21:49 GMT
From: sdd.hp.com!cs.utexas.edu!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Rational next station design process

In article <[e-mail]> [e-mail] writes:
>>The United States has no space program.
>>The last space program in the US was Apollo.
>
>Good frigging grief.

He's right, Nick.  You have no *program*.  You have a random collection
of missions, on the "he who screams loudest gets to fly next" principle.
Successes are not followed up.  Failures are not re-tried.  There is no
overall plan behind any of it, no priorities, no coordinated sequences of
missions that build on each other to achieve specific goals, no systematic
development of technology to make easy missions easier and hard missions
possible, no reflight opportunities for fruitful instruments or second
chances for ones that didn't make the cut the first time.
--
And the bean-counter replied,           | Henry Spencer @ U of Toronto Zoology
"beans are more important".             |  [e-mail]  utzoo!henry

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

Date: 23 May 91 11:18:33 GMT
From: mcsun!ukc!icdoc!syma![e-mail]  (Nick Watkins)
Subject: Re: space news from March 18 AW&ST

From article <[e-mail]>, by [e-mail] (Henry Spencer):
>
> Story about planned upgrades and possible future directions at the Cape.
> Current approaches to launcher and payload processing, and current launchers
> themselves, are considered inadequate for future activity.  "We've forgotten
> that launch vehicles are transportation systems."
Has interesting artist's impression of Cape in future. Appears to show pad
20 & pad 34 back in use. Anybody know which boosters they assumed to be
using them ( were once Titan I/II and Saturn I respectively)?

Also, has anybody any pics of Atlas Agana launches from pad 13 post 1969 ?
I'm interested in the late model of the Atlas Agena D.

Nick
--
Dr Nick Watkins, Space Plasma Physics, Univ. of Sussex, Brighton BN1 9QH, UK
JANET: [e-mail]        BITNET: [e-mail]

ISU Class of '91

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

Date: 22 May 91 16:20:06 GMT
From: agate!spool.mu.edu!rex!wuarchive!hsdndev!cfa203![e-mail]  (Steve Willner)
Subject: Re: What comes after Fred's death?

> In article <[e-mail]> I wrote:
>>...keeping a couple of astronauts in orbit for a year or so can be
>>done without a space station?

I'm glad this has generated so much discussion.

From article <[e-mail]>, by [e-mail] (Allen
W. Sherzer):
> you would need to arrange
> schedules so that the desired orbits of all the missions are compatable.

No harder than launching construction materials for a station.
Besides, you may get to take up some unrelated cargo on each mission.

> you still couldn't launch Shuttles fast enough

Recall that I suggested buying two more orbiters, giving a total of
six.  Current plans are 12 launches/year with four orbiters, aren't
they?  Processing and mission control facilities would have to be
beefed up, but no new development is required except for the extended
duration, which is already planned.

From article <[e-mail]>, by
[e-mail] (Henry Spencer):
> Much of the life-sciences work people would like to do involves experimental
> animals other than astronauts, and non-trivial amounts of hardware.  Taking
> it from one orbiter to another would be quite a job.

Large numbers of animals would be a problem, but small numbers could
be packaged for EVA and carried over.  Cages and other hardware would
have to be duplicated.  The disadvantage of duplication might be
partially offset by the advantage of using different kinds of
apparatus on the same experimental subjects and the ability to modify
apparatus as the mission proceeds.  It's not clear to me where the
balance lies.

From article <[e-mail]>, by [e-mail]
(Charles Frank Radley):
> Keeping the shuttle up longer than 30 days is not very practical.

With six orbiters, 30 days should be sufficient.

From article <[e-mail]>, by
[e-mail] (Frank Crary):
>  First of all, it would be nice to have a large sample of
> human subjects, e.g. 4 or more per year.

Nice, yes, but is it essential?  Remember we are spending _far_ less
than half the money.

> Second, it would be a real mental hardship (something I generally
> like to ignore.) for someone to spend a year in such a confined
> space

Might be a problem.  How does volume in Fred or Mir compare with a
Spacelab module?

[in private e-mail, someone suggested the cost would be too high]

Building two orbiters, additional mission control and processing
facilities, spacelab modules, and paying for all the launches has to
cost vastly less than Fred construction.  Perhaps just as important,
the costs can be determined in advance, since everything has been
done before.  (Except the extended duration, of course.)  There might
be additional savings if unrelated cargo can be launched on some of
the missions.

So far, the only potential show-stoppers I see are:
1) Extended duration orbiters (30 days) are not possible.
2) Necessary experiments cannot be conducted with hardware that will
be available.
3) Volume available is not sufficient for necessary experiments.

None of these seems plausible to me.

--
-------------------------------------------------------------------------
Steve Willner            Phone [phone]         Bitnet:   willner@cfa
60 Garden St.            FTS:      830-7123           UUCP:   willner@cfa
Cambridge, MA 02138 USA                 Internet: [e-mail]

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

Date: 22 May 91 18:15:01 GMT
From: agate!spool.mu.edu!rex!wuarchive!news.uu.net!valid!caber![e-mail]  (Louis K. Scheffer)
Subject: Re: Desaturation of the Reaction wheels on the Magellan Spacecraft

[e-mail] (Mark A Wieczorek) writes:


>    I've got a question for everyone out their. Why do the reaction
>wheels have to be desaturated on the magellan spacecraft?

Possible torques are:

>1) a frictional force coming from the upper atmosphere--how far does the
>venutian atmosphere extend anyways?

>2) momentum from the solar wind

>3) tidal forces acting on the spacecraft

>4) irregularities of the gravitational field of the planet

At least two others are:

   5) Interaction with magnetic field of planet.

   6) Leakage of thrusters

-Lou Scheffer

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

Date: 23 May 91 21:58:33 GMT
From: sdd.hp.com!zaphod.mps.ohio-state.edu!unix.cis.pitt.edu![e-mail]  (Judyth T Gibson)
Subject: Re: Gravity waves (was Re: LIGO (was Re: IT'S OVER))

>The idea of using gravity waves as a means of communicating through
>space was proposed by Larry Niven in a short story some time ago.  I
>don't remember the name of the story but it is included in the book
>"N-Space".
>
>It is an interesting idea but aside from the problem of detecting
>gravity waves, how would we (or anyone 'out there') generate them in
>an organized manner?  (Niven's story uses a primordial black hole
>contained in a magnetic bottle.)
>

Gravity waves... remined me of a cartoon I once saw.  There's this
uptight, somewhat angry scientist walking down the hall towards an open
door.  This scientists is saying "What's this nonsense I hear about
you discovering anit-gravity waves?"  Behind the open door (in a room) is
another scientist (we know they are scientists, by the way, because
they are wearing lab coats) on a surfboard, which is in mid air, apparently
riding an anit-gravity wave the way a surfer would ride a water wave.
It's probably funnier if you see it but this is one of my favorit
cartoons.

___
Practice a thousand times, and it becomes difficult; a thousand
thousand, and it becomes easy; a thousand thousand times a thousand
thousand, and it is no longer you that does it, but It that does
itself through you.  Not until then is that which is done well done.

Judy
[e-mail]

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

Date: 21 May 91 05:32:28 GMT
From: usc!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Kieran A. Carroll)
Subject: Re: Rational next station design process

In article <[e-mail]> [e-mail] writes:
>
>Instead of _assuming_ a design concept "space station", start with the
>question: "what do space users need?"  The major space users being
>defense, commerce (mostly communications), and exploration.
>
>If we start out with the question "what can we do with a manned
>space station", then of course we can make up some justifications
>for it.  If we start out with the question "what do space users need",
>then we can design the most useful infrastructure to extend our reach into
>space.  It may or may not have anything to do with a "space station" --
>we must examine many alternatives and be prepared to change or
>preconceived notions.
>

You're going in the right direction...now, take one >little< step
further back...

Try asking the question, "What is our long-term reason for carrying out
space exploration?" It's good for the soul for a space enthusiast to
occasionally ask himself what the basic reason is that people should
spend money on this stuff.

The United States has no space program.

The last space program in the US was Apollo. That was the last time
that you folks did spaceflight for a reason, with a goal in mind.
Given a goal, missions could be planned and carried out. You have
no goal now. You still carry out missions, but they are to no
particular end.

Many people working on spaceflight subscribe to an unofficial
goal, the expansion of human presence into the solar system and
beyond. This is "The Dream" that keeps NASA employees at work despite
low pay, lousy working conditions and a customer that doesn't really
want what they have to sell. This goal has never been officially
endorsed, however.

Until a goal has been adopted, asking what the needs are of space
users will not be very useful. Present space users have most of what
they need already --- communications satellites are quite profitable
without the need of any further government action (thanks, of course,
to the billions of dollars of government investment that was used
to found their industry, and was never recouped). The needs of
the future users of space cannot be assessed, without deciding
the direction a hypothetical space program will take --- that is
to contingent on adopting a goal for space exploration, and a plan for
accomplishing that goal.
--

     Kieran A. Carroll @ U of Toronto Aerospace Institute
     uunet!attcan!utzoo!kcarroll [e-mail]

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

End of SPACE Digest V13 #629
*******************