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Subject: SPACE Digest V9 #258

SPACE Digest                                      Volume 9 : Issue 258

Today's Topics:
              Re: MARS the Movie
             Re: NSS and space settlement
             Re: NSS and space settlement
                 Photography
              Re: 1992 moon base
          Orbital debris study completed (Forwarded)
            Re: question.shuttles
----------------------------------------------------------------------

Date: 20 Feb 89 23:19:18 GMT
From: [e-mail]  (Mike Smithwick)
Subject: Re: MARS the Movie

In article <[e-mail]> [e-mail] writes:
<
<
<I have seen all these videos and I must compliment the Image Processing
<people here for an excellent job!   The next movie is "Gallium Arsenide
<the Movie".

What I'm really waiting for is >>> Henry Spencer the Movie <<<

:-)


>
--
          *** mike (cerbral GURU, insert M&Ms to restart) smithwick***
"The great thing about standards is that there are so many of them!"

[disclaimer : nope, I don't work for NASA, I take full blame for my ideas]

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

Date: 20 Feb 89 22:56:53 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: NSS and space settlement

In article <[e-mail]> [e-mail] (Nick Szabo) writes:
>>please name a date, or cite specific criteria that would indicate
>>that the time is at hand.
>
>Criteria:  A manned mission or base is desirable when
>1) It can return discoveries and/or resources, unrelated to further manned
>spaceflight, that are equivalent or better than what can be done by spending
>the same money on unmanned missions.
>OR
>2) It cannot quite meet criteria (1), but the costs are borne by the
>mission promoters, not taxpayers or stockholders.

On the whole I agree with this, but with a couple of important reservations.

First, I don't understand the mention of stockholders in (2) -- stockholders
can always take their money elsewhere if they don't like what the company
is doing.  Their *purpose* is to provide capital for the company; it is
silly to say that they shouldn't bear the costs of a speculative venture.

Second, more important, the "unrelated to further manned spaceflight" part
of (1) basically gives us the same situation that is ruining North American
industry:  only immediate returns are of interest; long-term planning and
investment in the future is forbidden.  Not a promising policy.
--
The Earth is our mother;       |     Henry Spencer at U of Toronto Zoology
our nine months are up.        | uunet!attcan!utzoo!henry [e-mail]

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

Date: 21 Feb 89 03:51:36 GMT
From: right![e-mail]  (Nick Szabo)
Subject: Re: NSS and space settlement

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>In article <[e-mail]> [e-mail] (Nick Szabo) writes:
>>Criteria:  A manned mission or base is desirable when
>>1) It can return discoveries and/or resources, unrelated to further manned
>>spaceflight, that are equivalent or better than what can be done by spending
>>the same money on unmanned missions.
>>OR
>>2) It cannot quite meet criteria (1), but the costs are borne by the
>>mission promoters, not taxpayers or stockholders.

>On the whole I agree with this, but with a couple of important reservations.
>First, I don't understand the mention of stockholders in (2)

Stockholders expect a return on their investment.  If a company promises such
a return, but does not come through, the stockholders are cheated and future
investors will be reluctant to invest in that industry.  (2) applies to those
people ready and willing to sacrifice their own resources; this excludes normal stock-market investors.

>Second, more important, the "unrelated to further manned spaceflight" part
>of (1) basically gives us the same situation that is ruining North American
>industry:  only immediate returns are of interest; long-term planning and
>investment in the future is forbidden.  Not a promising policy.

The reference is to "further manned spaceflight", not the future.
I specifically included that phrase because the argument, "we should
do manned spaceflight now for the sake of manned spaceflight in the future",
is self-referencing and self-absorbed.  (And wrong anyway, because as I
have pointed out the best thing we can do for manned spaceflight in the
future is unmanned spaceflight and basic R&D now).  The space program cannot
endure as a welfare case.




Nick Szabo              [e-mail]

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

Date: 19 Feb 89 21:19:51 GMT
From: bgsuvax![e-mail]  (Scott F. Brown)
Subject: Photography


    Hello.  In the near future, I will be using our university's 1/2
meter for photography.  I will be using Tri-x film for starters.  What I
would like to know is recommended exposure and F-stop settings for the
following objects:

    1 : The moon
    2 : Brighter planets (Jupiter / Venus)
    3 : Dimmer planets (Mars, Mercury, Saturn)
    4 : Remaining planets
    5 : Bright deepsky objects (M42, M31)
    6 : Faint deep sky (M81, M33)
    7 : Meteor storms (no telescope)
    8 : Milky wat (no telescope)

    An additional note:  Anything taken through the telescope has
the misfortune of the campus lighting.  The sky in Bowling Green is bright
and causes many stars to not be visible.  Thanks in advance.

                    - Scott F. Brown

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

Date: 21 Feb 89 04:37:32 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: 1992 moon base

In article <[e-mail]> [e-mail] (Paul Dietz) writes:
>One additional problem with the shuttle (vs. the Saturn V) is that a
>lunar vehicle launched by the shuttle must use solid or storable
>propellant rockets to leave earth orbit, rather than oxygen/hydrogen,
>unless you are proposing to refuel in orbit with propellants launched
>by something other than the shuttle.

Don't forget that the first Shuttle/Centaur launch was only a few months
away when Challenger was lost.  A shuttle-based plan made *today* cannot
assume oxygen/hydrogen without orbital assembly or something like that,
but before January 1986 oxygen/hydrogen was a reasonable choice of fuel.
--
The Earth is our mother;       |     Henry Spencer at U of Toronto Zoology
our nine months are up.        | uunet!attcan!utzoo!henry [e-mail]

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

Date: 21 Feb 89 06:29:01 GMT
From: [e-mail]  (Peter E. Yee)
Subject: Orbital debris study completed (Forwarded)

Jim Cast
Headquarters, Washington, D.C.                  February 17, 1989

Pam Alloway
Johnson Space Center, Houston

Lt. Col. Rick Oborn
Department of Defense, Washington, D.C.


RELEASE:  89-20

ORBITAL DEBRIS STUDY COMPLETED


     The U.S. Government today released results of a 6-month
interagency study on orbital debris.

     The study, co-chaired by NASA and the Department of Defense,
cites satellite and rocket body fragmentation as the principal
source of orbital debris and concludes that, left unchecked, the
growth of debris could threaten the safe and reliable operation
of manned and unmanned spacecraft in the next century.

     A major finding concerns the limits of our knowledge about
the current population of orbital debris objects.  While the U.S.
Space Command routinely tracks objects in space that are larger
than a softball (about 10 centimeters and larger), the ability to
track smaller objects is hampered by system design.  The
uncertainty, therefore, as to exactly how much debris is in orbit
makes it difficult to assess the true risk posed to spacecraft.
This, in turn, creates uncertainty as to the urgency for action
and the potential effectiveness of any corrective action.  The
report states that the need for enhancing debris measurement
capabilities "has been universally recognized."

     The report reviews current policies and activities designed
to reduce debris or mitigate its effects and explores potential
opportunities for further action.  International efforts, legal
issues and commercial regulation also are examined.

     Along with NASA and DOD, other federal organizations
participating in the orbital debris study included the
Departments of State, Commerce, Transportation and Treasury as
well as the Office of Management and Budget, Federal
Communications Commission and the Intelligence Community Staff.

     A fact sheet concerning the orbital debris study follows.
Limited quantities of the report itself are available in the
newsrooms of NASA Headquarters, Johnson and Kennedy Space Centers
and at the Office of Secretary of Defense/ Public Affairs.
------------------------------------------------------
                                                February 17, 1989

    ORBITAL DEBRIS STUDY

     The U.S. government today released the Interagency Group
(Space) Report on Orbital Debris.

     The report is the culmination of an intensive 6-month study,
which was initiated in response to a directive contained within
the National Space policy approved by President Reagan in
February 1988.  The directive stated that "all space sectors will
seek to minimize the creation of space debris.  Design and
operations of space tests, experiments and systems will strive to
minimize or reduce accumulation of space debris consistent with
mission requirements and cost effectiveness."

     An interagency working group was tasked last July by the
National Security Council to review the extent of the orbital
debris problem, identify options for minimizing or reducing the
accumulation of orbital debris and its impact on future space
activities and recommend courses of action.  The group was co-
chaired by senior officials from NASA and DOD and included
representatives from the departments of State, Commerce,
Transportation and Treasury, as well as the Office of Management
and Budget, the Federal Communications Commission and the
Intelligence Community Staff.

     The report is written in concise, non-technical language.
It begins with a description of the current space environment, a
discussion about the major sources of debris, and an assessment
of the implications of current debris growth trends.  It then
reviews current policies and activities designed to reduce debris
or mitigate its effects and explores potential opportunities for
further action.  International efforts, legal issues and
commercial regulation also are examined.

     According to the report, the principal source of orbital
debris has been fragmentation of satellites and rocket bodies.
Other sources include inactive satellites and objects discarded
during satellite delivery or operations, such as lens caps,
packing devices or empty propellant tanks.  The report concludes
that, left unchecked, the growth of debris could threaten the
safe and reliable operation of manned and unmanned spacecraft in
the next century.

     A major finding of the report is that not enough is known
about the extent of the problem posed by small debris in the
orbital environment.  Although the U.S. Space Command routinely
tracks objects in space that are larger than about 10 centimeters
in diameter, the limited ability (a design limitation) of current
surveillance systems to detect and track the much greater number
of small debris objects creates high uncertainty in the debris
environment models that scientists have constructed.  This makes
it difficult to assess the true risk posed to spacecraft by
orbiting debris, which in turn creates uncertainty as to the
urgency for action and the potential effectiveness of any
corrective measure.  The report states that the need for
enhancing debris measurement capabilities "has been universally
recognized."

     The report's recommendations call for appropriate agencies
to make debris minimization a design consideration for all future
civil, military and commercial launch vehicles, upper stages,
satellites, space tests and missions.  This would include
promulgating and implementing agency-level internal policy
guidance consistent with the debris minimization directive of the
National Space Policy.  The report also recommends that NASA and
DOD undertake a joint study to develop a comprehensive R&D plan
to improve orbital debris environment monitoring, statistical
modeling and data management capabilities.  A second joint study,
to be undertaken by NASA and DOD in consultation with the
Department of Transportation and the commercial space sector,
would construct a basic research plan for developing technologies
and procedures for debris minimization and spacecraft
survivability.

     The report further recommends a continuing dialog between
the federal government and industry, recognizing that any
imposition of requirements on the private space sector to control
or prevent the proliferation of space debris will have important
commercial implications.

     The report also includes these recommendations:

--  Current agency operational practices for debris mitigation
during launch and space operations should be continued and, where
feasible and cost-effective, improved.

--  The following activities should be emphasized and, where
appropriate, accelerated:

        - efforts to improve debris characterization measurements
          and inventory through use of ground-based radars and
          development of an improved data base

        - modeling and statistical analysis of the debris
          characterization measurements

        - analysis of physical evidence returned from space

        - technological research directed toward improved
          spacecraft shielding and a better understanding of the
          fragmentation processes that result from hypervelocity
          collisions

        - licensing agency development of performance
          requirements and regulations to guide private industry
          activities

        - ongoing studies of design and operations techniques to
          minimize the cost of debris elimination

--  Representatives of commercial licensing agencies (DOT, DOC
and FCC) should continue their discussions to define the
boundaries of regulatory authority among the licensing agencies
over commercial activities that may produce orbital debris.

--  An ad hoc interagency working group on orbital debris,
chaired by NASA and DOD, should be retained as a coordinating
mechanism for issues, policies and activities concerning the
orbital debris problem.

--  The U.S. should inform other spacefaring nations about the
conclusions of this report and seek to enhance understanding
about orbital debris issues.  As appropriate, the U.S. should
enter into discussions with other nations to coordinate debris
minimization policies and practices.

--  Within 18 months, an interagency working group should develop
a long-term strategy for researching, developing and implementing
means to minimize the accumulation of orbital debris and protect
spacecraft operations (within an acceptable level of risk) from
collision with debris objects.  As a minimum, this strategy
should include establishing long-range goals, providing a
milestone plan and schedule leading to achievement of these long-
term goals, and preliminary resource implications.

     The Interagency Group (Space) Report on Orbital Debris is
being prepared for printing, and finished copies will be
available for distribution by early April 1989.  Meanwhile, a
limited number of photocopies is now available upon request.

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

Date: 21 Feb 89 04:42:36 GMT
From: mailrus!jarvis.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: question.shuttles

In article <[e-mail]> [e-mail] (Lord Shadowhawk) writes:
>I'm just curious if anybody knows whether or not two space shuttles can be
>launched simultaneously.....like the Atlantis and Discovery??

There is no theoretical reason why it can't be done, since all the big
hardware (VAB bays, launch platforms, pads, control rooms) is at least
duplicated, but the current processing and support organization is very
much keyed to one launch at a time.  Also, not all of that duplicated
equipment is really ready to go -- pad 39A is not up to 39B standard
at present, for example, and I'd suspect that there's only one fully
up-to-date control room.
--
The Earth is our mother;       |     Henry Spencer at U of Toronto Zoology
our nine months are up.        | uunet!attcan!utzoo!henry [e-mail]

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

End of SPACE Digest V9 #258
*******************