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Subject: SPACE Digest V11 #595

SPACE Digest                                     Volume 11 : Issue 595

Today's Topics:
            Re: HST focus problem
            Re: HST Focus problem
            Re: HST focus problem
               Re: public image of HST
             gravity and the hubble lens
            Re: Physiology in microgravity
       Re: RE  Hubble Space Telescope Update - 06/28/90
     Re: NSS protests Chinese launch pricing (The Letter)

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

Date: 29 Jun 90 20:59:40 GMT
From: cs.utexas.edu![e-mail]  (Donald A. Varvel)
Subject: Re: HST focus problem

I have a simple request for information here.

Earth-bound telescopes are pointed in a variety of directions, from
horizontal to vertical.  The optics do not deform significantly.
I have difficulty believing that a mirror that holds the same
figure whether on edge or pointing straight up would have a significantly
different figure in microgravity.  Now, these are optics designed
for working that way.

Presumably the HST optics were not designed to be useful on the
earth's surface.  Are the mirror substrates thinner than usual?
I can easily believe they would be, to save weight and because
thicker glass is not necessary in microgravity.  Still, I would
be interested in confirmation.

This is _not_ to suggest that the usual earthbound mountings would
be appropriate for space.  It is only to say that the optics would
work there.

-- Don Varvel ([e-mail])

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

Date: 29 Jun 90 23:53:38 GMT
From: uvaarpa!murdoch!astsun8.astro.Virginia.EDU![e-mail]  (Greg S. Hennessy)
Subject: Re: HST Focus problem

Robert Dempsey

#Greg Hennesy commented that the spectral resolution will be lower.  I
#presume he was referring to WFPC as the high res spectrograph should
#not suffer losses in resolution, just throughput.  However, if one
#wants to look at faint objects lower res will need to be used.

No, what I was thinking is that the rule of thumb is that the spectral
resolution gets better as you make the slit smaller, untill the slit
is the seeing disk. Thus the better the seeing, the better the
spectral resolution. I think that for stars the spectral resolution
would not be degraded, but I think (but am not positive) that the
spectral resolution would be degraded.


--
-Greg Hennessy, University of Virginia
 USPS Mail:     Astronomy Department, Charlottesville, VA 22903-2475 USA
 Internet:      [e-mail]
 UUCP:        ...!uunet!virginia!gsh7w

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

Date: 30 Jun 90 02:26:15 GMT
From: uoft02.utoledo.edu![e-mail]
Subject: Re: HST focus problem

In article <[e-mail]>, [e-mail] (Donald A. Varvel) writes:
> I have a simple request for information here.
>
> Earth-bound telescopes are pointed in a variety of directions, from
> horizontal to vertical.  The optics do not deform significantly.
> I have difficulty believing that a mirror that holds the same
> figure whether on edge or pointing straight up would have a significantly
> different figure in microgravity.  Now, these are optics designed
> for working that way.
>
>

This not correct.  Telescope and instrument flexure can be significant
on ground based telescopes.  However, this can be countered by throwing
stronger and heavier materials in, a luxury you don't have when launching
with payload restrictions.  Even if there are changes they may be lost
in the seeing which are then serious when you are trying to observe
at the diffraction limit.  The larger the telescope the more massive
the structure.

Robert Dempsey
Ritter Observatory

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

Date: 29 Jun 90 15:55:02 GMT
From: dinl![e-mail]
Subject: Re: public image of HST

In article <[e-mail]>, [e-mail] (THOMAS DAVID J) writes:
>
> I must agree that the general public will probably react to the current events
> in the manner Mr. Palfreyman describes.  However, as Ron Baalke at JPL has
> pointed out, the mechanisms of the HST are too sensitive to be tested in
> Earth-normal gravity.
>
> Our space program, as old as it is, is still quite experimental.  With
> investments (scientific and financial) as large as the HST, there are bound
> to be risks.  However, I believe that the potential benefits are well worth the
> risks.

I generally agree; however, risks must be mitigated by sound
NASA and contractor management.


===================================================================

--------------> rich <-------------- ([e-mail])

Martin Marietta Information Systems Group | Accept AI for what it can
Box 1260                                  | do, just as we accept
MS XL8058                                 | the 747 because it can
Denver, Colorado 80201-1260               | fly fast and carry lots
                                          | of people; don't criticize
[phone]                            | the plane because it
                      | doesn't sing or perch well
                      | on branches.

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

Date: 29 Jun 90 11:18:11 GMT
From: voder!dtg.nsc.com![e-mail]  (Lord Snooty @ The Giant Poisoned Electric Head )
Subject: gravity and the hubble lens

if the problem is really microgravity (rather than a defective spec)
i would have thought that, given accurate surface profile measurements
and six years of computer time, the effects of gravity changes on the
performance would be well understood. after all, the bulk modulus of
the material is known...

if it's a design flaw, one can equally well point the finger.
i am not happy.
--
...........................................................................
Andrew Palfreyman    that asteroid has our names on it
[e-mail]            " 'course, the 'addock's very nice "

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

Date:         Fri, 29 Jun 90 15:07:08 CDT
From: John Nordlie <[e-mail]>
Subject:      Re: Physiology in microgravity

The effects on humans of living in a microgravity environment are
begin intensively studied, but has anyone heard of any research
being done on so-called "atrificial gravity" produced by spining
a spacecraft?

A group of engineering students here at the University of North
Dakota came up with the idea of using a space station module,
a space shuttle external tank, and some kevlar ropes to construct
a "Variable Gravity Research Facility", which would investigate
atrificial gravity's effects on people and things.  In their
plan, the module was connected to the ET (external tank) by
kevlar ropes.  The assembly was then spun up to 3 rpm, and the
intensity of the artificial gravity varied by changing the
lengths of the ropes.

The idea was presented to NASA and the aerospace community at
a conference last summer at Huntsville, Alabamma.  (All the
engineering students had graduated, so I was handed the paper
and told to present it.  Ever see a comp. sci. student lecture
professional engineers about space hardware?)  It seemed a
good idea, but have heard no more about it.

What are your opinions about the effectiveness of "artificial
gravity" and the need to build a research facility to study it?

PS A fellow from Martin Marietta told me they had done some
   tests that show people can be spun up to 6 rpm without getting
   motion sickness.







=======================================================================
John Nordlie   |   I tried to think of something intelligent to say.
               |    " Urgh..", I managed.
               |               - Harry Harrison 'A Stainless Steel Rat
               |                                 is Born'
=======================================================================

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

Date: 30 Jun 90 03:32:14 GMT
From: ogicse!plains![e-mail]  (Glen Overby)
Subject: Re: RE  Hubble Space Telescope Update - 06/28/90

In article <[e-mail]> [e-mail] (Doug Mohney) writes:
>If Hubble was run on a shoe-string budget, instead of big bucks...well...
>I can't help but think the thing would have A) Gotten off the ground about
>4 years sooner and B) Given us more than we bargained for.

HST was trundled across the country for launch two previous times, but was
delayed both times by shuttle problems.  Complaint "A" above isn't the HST
project's fault (except that they should have chosen a different booster).

As for "B", we'll have to wait and see what we DO get out of HST.  We won't
get as many initial "pretty picures", but the information content could be
just as good.

--
        Glen Overby    <[e-mail]>
    uunet!plains!overby (UUCP)  overby@plains (Bitnet)

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

Date: 30 Jun 90 03:27:00 GMT
From: usc!venera.isi.edu![e-mail]  (Craig E. Ward)
Subject: Re: NSS protests Chinese launch pricing (The Letter)


/*
 * Here is the letter the NSS sent to the USTR.  We've been arguing about
 * it enough that I thought it reasonable to get an online copy.  It outlines
 * why the protest and why the USTR should do something about it.  While it
 * emphasizes the US industry, -- it is to the *US*TR-- its logic applies to
 * every other country that has a private launch industry.
 *
 * This is courtesy of Glenn Reynolds, Chair of the NSS Legislative Committee.
 *
 * cew
 */


                              June 15, 1990





The Honorable Carla Hills
United States Trade Representative
Executive Office of the President
Washington, DC  20500

Dear Ambassador Hills:

     I am writing in order to direct your attention to a serious
problem facing a new and strategic industry.  I refer to the
problem of unfair trade practices on the part of the People's
Republic of China in the area of commercial launch services.

     The commercial launch services industry is a strategic
industry, providing an essential input to virtually all space-
related goods and services:  satellite hardware, space
manufacturing, remote sensing, communications, etc.  The
civilian space industry accounted for nearly $25 billion in sales
and 210,000 employees in 1987.  According to Norman Augustine,
CEO of Martin Marietta, each commercial Titan launch offsets the
import of 10,000 Toyotas.  That is why the commercial launch
industry has been identified as a vital national priority by both
the Executive branch and Congress.  Moreover, the United States
is truly a technology leader in this vital area, with a number of
established competitive firms including General Dynamics, Martin
Marietta, and McDonnell Douglas, as well as numerous "start up"
companies such as the American Rocket Company, Orbital Sciences,
and Space Services, Incorporated.

     No industry can flourish, however, in the face of
government-sponsored competition.  Unfortunately, that appears to
be precisely the kind of competition that the Chinese are
offering.  Beginning over two years ago, the Chinese government
has offered launches on its Long March vehicle at prices of $20-
30 million dollars -- about half the price of a comparable
commercial launch on a U.S. or European vehicle.  Such pricing is
below cost, and constitutes an unreasonable, unjustifiable burden
on United States commerce.

     Continuation of this practice also constitutes the violation
of a trade agreement.  After many complaints from the United
States launch industry in 1988, U.S.T.R. arrived at an agreement
with the Chinese government under which the Chinese were to limit
the number of launches offered to no more than nine over a six
year period, during which the launches would be spread evenly,
and to price those launches on terms "on par with those. . .
prevailing in the international market for comparable commercial
launch services."  It appears, however, that the Chinese are not
abiding by this agreement.  Published reports suggest that the
recent Chinese bid to launch for the Arabsat consortium is again
in the $20-30 million range, the same kind of price charged by
the Chinese before the agreement was signed and well below the
commercial rate in the United States or Europe.  Arianespace
officials have complained that the price is 50% below normal and
amounts to dumping.  Gerald Musarra of the Office of Commercial
Space Transportation is quoted as saying, "That certainly seems
to be totally at odds with the terms of the agreement with the
Chinese."

     As is hardly necessary for the National Space Society to
point out, these circumstances seem to support (indeed, to
mandate) action on a petition under Section 301 of the Trade Act
of 1974, for violation of a trade agreement.  NSS is seriously
considering the possibility of filing such a petition concerning
the Chinese practices.  However, we encourage you to make such a
petition unnecessary by taking prompt action on your own
initiative in response to the Chinese practices.

     It is worth stressing that NSS does not want to limit fair
competition in the launch services industry; in fact, NSS
strongly favors such competition as a means of promoting new
technology and lowering costs in the launch field.  The Chinese,
however, are not offering fair competition.  If China were to
abide by its international commitments on fair pricing and number
of launches, NSS would not be concerned.  If China refuses to
abide by those commitments, however, the impact will be severe
not only for the U.S. launch industry, but ultimately for the
payload sector -- and the future of the entire U.S. commercial
space industry -- as well.  The United States must act promptly
to prevent such an outcome.

     Such action must be firm, and (given the apparent failure of
the 1988 agreement to end the Chinese practices) may require the
imposition of sanctions as a means of persuading the Chinese
government that the United States is serious about this matter.
NSS also urges USTR to consult closely with European interests,
who are equally concerned about unfair Chinese pricing.

     We are prepared to meet with you at your earliest
convenience to discuss these matters further, and to offer
whatever assistance NSS may provide in bringing this matter to a
swift conclusion in favor of the United States launch industry
and fair competition.  NSS is a nationwide pro-space organization
made up of tens of thousands of members who support the creation
of a spacefaring civilization, a goal also endorsed by President
Bush.  NSS has repeatedly spoken and acted in favor of the
development of a truly competitive commercial space launch
industry, another goal we share with the President.  For such an
industry to develop, however, competition must be on the basis of
prices that reflect efficiency, reliability, and technical
quality.  Government subsidies and "dumping" distort such
competition, since in a government-subsidized pricing regime the
"price" charged is purely arbitrary and may reflect no more than
the desire of the government in question for hard currency,
national prestige, or technological development for national
economic or military purposes.  Competition distorted by dumping
and government subsidies will not provide the incentives for
efficiency, technology development, and real cost reduction that
a truly free market will provide.

     Given the vital role of the commercial space launch industry
for our nation's future, we cannot afford to allow the American
companies involved to be extinguished by unfair foreign
competition.  NSS asks that you act to end the Chinese practices
immediately.

                              Sincerely,



                              Lori Garver
                              Executive Director,
                              National Space Society

--
Craig E. Ward <[e-mail]>     Slogan:    "nemo me impune lacessit"
USPS:    USC/Information Sciences Institute
    4676 Admiralty Way, Suite 1100
    Marina del Rey, CA 90292

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

End of SPACE Digest V11 #595
*******************