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Subject: SPACE Digest V12 #498

SPACE Digest                                     Volume 12 : Issue 498

Today's Topics:
             --- Space Station Budget ---
            Re: Magellan Update - 10/24/90
             Re: Theories needed on life
             Re: Theories needed on life
          Re: Some interesting SSME specifications.
          Re: Info wanted on Space Plane and Pegasus
                 Re: Ulysses
              Magellan Update - 10/26/90
            Re: Magellan Update - 10/26/90

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: 25 Oct 90 12:20:00 GMT
From: usc!zaphod.mps.ohio-state.edu!caen!dahm.engin.umich.edu![e-mail]  (Ken Sheppardson)
Subject: --- Space Station Budget ---


  Well folks, here's what we've got to work with now.

  I don't make the news, I just report it...


------------------------------(cut here)------------------------------


         VA/HUD/IA HOUSE-SENATE CONFERENCE REPORT, HR101-900
             MAIN POINTS REGARDING SPACE STATION FUNDING
                          OCTOBER 16, 1990

   o 1.9B for Space STation; a cut of 551M

   o Includes 106.3M for FTS

   o Includes 10M for solar dynamic power research

   o NASA should consider the possibility of an incremental
     approach to Space Station:

     ---begin man-tended capability
     ---followed by manned capability
     ---conclude with permanently manned capability

   o Maximum annual growth in NASA's budget cannot exceed 8-10%

   o NASA is to immediately implement a revised Space Sation
     design and assembly sequence with reflects an incremental
     approach:

     ---assumes outyear growth in Sation funding profile
        of approximately 10% per year with a peak year
        funding of 2.5B to 2.6B
     ---this could yield a man-tended capability on orbit
        as early as flight three or four of the assembly
        sequence
     ---NASA is to make its recommendation within 90 days
        of enactment of this bill
     ---incremental concept should permit each phase to be
        discrete and independent of the next phase

   o Space Station is capped at 640M in the interim, or 160M per
     month (will consider an extension or increase if necessary)

   o First Space Station phase should be devoted to a
     microgravity function, followed by a life science function
     and permanent manned capabillity

   o Each phase should be sufficiently independent to achieve on
     orbit operation of the phase should new funding threats
     evolve

   o It is doubtful if today's Space Sation design could be
     supported by the current launch system. Any rescoping
     should consider a realistic shuttle launch rate

   o 90-study should include principles previously committed
     to by NASA:

     ---a fully equipped U.S. microgravity laboratory
        before the launch of any habitat
     ---a requisite number of utilization flights per annum
        following the launch of the U.S. microgravity
        laboratory
     ---life science, centrifuge, and related support
        equipment shall be place in an area other than the
        U.S. microgravity laboratory
     ---a total of 75 kW of power (if all phases of the
        Station are developed) with at least 30 kW for the
        users and with power and modules added in
        increments that will ensure that user power will
        not be seriously degraded

   o NASA must redirect its efforts to designing a Space Station
     that incorporates an early manned capability and can be
     accomodated within the anticipated outyear funding
     available in the domestic discretionary spending area

   o A cut of 16M from the assured crew rescue vehicle

   o A cut of 12M from the 15M requested for integrated and
     attached payloads

   o 31M from engineering and techincal base and payload
     operations and support equipment to be allocated at the
     Agency's discretion

   o A cut of 15M from the 15M requested for Neutral Buoyancy
     Laboratory

   o A cut of 2.3M and 46 FTEs [Full-Time Equivalents] from the
     Space Station Level II office [Reston]

   o During fiscal year 1991, average employment in the
     headquarter's offices of NASA shall not exeed...482 staff
     years for the Office of Space Flight, including Level I [DC] and
     Level II activities for the Space Station...no funds may be
     used for details of employees from any organization in NASA
     to any organization included under the budget activity
     "Research and Program Management" except those details
     which involve developmental or critical short-term staffing
     assignments

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

Date: 25 Oct 90 15:09:41 GMT
From: idacrd![e-mail]  (Robert McGwier)
Subject: Re: Magellan Update - 10/24/90

From article <[e-mail]>, by [e-mail] (Ron Baalke):
>
>                     MAGELLAN STATUS REPORT
>                       October 24, 1990
> The Sun-earth-Magellan angle is now 2.5 degrees.
>     ^^^^^^^^^^^^^^^^^^^


Am I wrong in assuming that since we are near superior conjunction that
you meant Earth-Sun-Magellan.  It is amazing that the X band stuff is making
it past all the solar noise being generated at X band.  Using black body
radiation formulae (I don't even know if this correct), my guesstimate
as to the half power beamwidth's of the 70 meter dishes, it is quite
remarkable that we are still having good copy on the telemetry.

Thanks for the updates!

Bob

--
____________________________________________________________________________
    My opinions are my own no matter    |    Robert W. McGwier, N4HY
    who I work for! ;-)            |    CCR, AMSAT, etc.
----------------------------------------------------------------------------

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

Date: Thu, 25 Oct 90 21:51:27 EDT
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: Re: Theories needed on life


>From: usc!srhqla!demott![e-mail]  (Kevin D. Quitt)
>Subject: Re: Theories needed on life

>In article <[e-mail]> [e-mail] (Jenni Sheehey) writes:
>>It really *is* unlikely that anything even resembling *any* species
>>presently on earth would be found on another planet by chance...

>    Unless you actually have proof of this, please label it as opinion.
>Based on our profound lack of knowledge, it is equally likely that *most*
>earth-like planets would develop humanoid life.

"Equally likely" is a very slippery term. As you point out, likelihoods are
presented based on current knowledge, but I believe there is sufficient
information available to make an initial estimate, and I don't think the
calculated odds are likely to come out 50-50. Certainly, the calculation is
not simple, and there is a significant possibility of leaving out important
factors. This might make a good topic for a doctoral dissertation.

In reference to the original question, one possibility is that evolutionary
forces might produce organisms of the same general structure as the ones
found on earth, but with significant differences in detailed structure and
in biochemistry. If there are intelligent life forms, they might form a
society and a body of logic so alien to ours that there is little common ground.

What doesn't seem to be mentioned much is the significance of the fact that
our ecosystem evolved as a collection of organisms. A major part of our
structure appears to be designed to facilitate interaction with our fellow
creatures. Subtle feedback mechanisms are involved, and there may have been
many points at which the collective course of evolution could have taken
a different turn. Anything evolving outside of our specific ecosystem
may have been subjected to very different evolutionary forces.
       John Roberts
       [e-mail]

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

Date: 26 Oct 90 01:30:53 GMT
From: vsi1!hsv3![e-mail]  (Mike Van Pelt)
Subject: Re: Theories needed on life

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>... and humans can and did (as of a few years ago, still do) hunt
>things like antelope by chasing them until they drop from exhaustion.

There was a fascinating article in Analog a year or so ago, which
discussed the theory that humans are actually pretty well adapted as
cursorial hunters.  American Indians used to hunt horses by the "chase
'em 'till they drop" method.  A manager at Unisys was written up in the
company newsletter for running a 100 mile ultramarathon course in under
24 hours.  He did not come in first place.  There are *very* few
animals that can do this.
--
Mike Van Pelt       | "I am too controlled, I am too clear, I am too
Headland Technology |     mature to be angry."  -- Jesse Jackson.
(was: Video Seven)  | [Clear?  I didn't even know he was into Dianetics.]
...ames!vsi1!v7fs1!mvp

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

Date: 25 Oct 90 16:26:06 GMT
From: mnetor!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Some interesting SSME specifications.

In article <[e-mail]> [e-mail] (Matt Taylor) writes:
>[ On a related note, wasn't there supposed to be a beefed up
>version of the current SSME due to be incorporated into the shuttle
>sometime soon? ]

There is work in progress on a new "powerhead" -- pumps, valves, and
injectors -- for the SSMEs, but it's still some ways from completion,
and there is no firm plan to actually use it for flight.
--
The type syntax for C is essentially   | Henry Spencer at U of Toronto Zoology
unparsable.             --Rob Pike     |  [e-mail]   utzoo!henry

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

Date: 26 Oct 90 05:09:33 GMT
From: swrinde!zaphod.mps.ohio-state.edu!samsung!munnari.oz.au!metro!nuts!frey![e-mail]  (Luke Plaizier)
Subject: Re: Info wanted on Space Plane and Pegasus


    There was an excellent article on Pegasus in the October Issue
of Ad Astra. If you know anyone with a copy, i suggest you read it. I have
even contemplated writing NSS to tell them how well that article
was written.
    Luke.

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

Date: 26 Oct 90 06:41:53 GMT
From: usc!elroy.jpl.nasa.gov!jato!mars![e-mail]  (Ron Baalke)
Subject: Re: Ulysses

In article <[e-mail]> [e-mail] (Robert W Murphree) writes:
>Dear Ron Baalke:
>
>Could you comment, either by E-mail or in sci.space or sci.astro about the
>possibility of an extended mission for Ulyssess?  After 1995 comes and the
>south pole of the sun is past, what's to stop Ulyssess from making the
>trip again and again?  What does the orbit evolve too?  Also, will the
>mission be limited by 1)expendables-attitude gas 2) power from the RTG
>etc. Is there political support at ESA for an extended mission?  Is JPL
>providing the communications and ESA the operations or what? Thanks..
>

     There are currently no official plans for an extended mission for
Ulysses after 1995.  However, that doesn't mean there will not be one.
The main contraints on an extended mission will be the power output from
the RTG's and available hydrazine fuel.  At launch, Ulysses was receiving
285 watts from the RTG's, and was carrying 33 kg of hydrazine.  At the
end of its primary mission in 5 years, the power output from the RTG's
will have dropped to 250 watts, which is enough to fully power Ulysses, but
will continue to dwindle as time goes on.  The amount of hydrazine left at
that time is unknown as that is dependent on how much is used for trajectory
course corrections.

     After 1995, Ulysses will be undoubtedly be tracked by the Deep Space
Network for as long as possible, such as what is being done with the Pioneers
and Voyagers.  After a gravity assist from Jupiter in 1992, Ulysses will be
in a highly eccentric solar orbit with a period of 6 years, extending from
the orbit of Jupiter to about 1.4 AU from the Sun.  When Ulysses loops back
around for another solar pass in 1999-2000,  the power available from the
RTG's will not be sufficient of support a fully functional spacecraft; however,
a limited mission is possible to make further measurements of the Sun. Also,
with Ulysses having an orbital period of 6 years, and Jupiter having an orbital
period of 11.9 years, the two will come in close proximity of each other in
the year 2004.  If enough hydrazine is still left, a course maneuver burn
could possibly be performed to get the spacecraft close enough to Jupiter for
another gravity assist.  If this is possible, then this opens the door to
a number of possibilities of where to send the spacecraft next.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

Date: 26 Oct 90 17:48:21 GMT
From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Magellan Update - 10/26/90


                           MAGELLAN STATUS REPORT
                             October 26, 1990

     As the Magellan mission approaches Superior Conjunction, the project has
reviewed daily the increasing difficulties with telecommunication, navigation,
spacecraft performance, and radar data quality.  The basic question was not
whether to suspend mapping, but when.

     A decision was made to suspend mapping at the end of orbit #676, 6:33 AM
PDT on Friday, October 26.  The spacecraft stopped its mapping maneuvers, and
will hold its position with the High Gain Antenna pointed to earth and the
solar panels directed toward the sun.  The radar sensor remains in standby
mode.

     Although the high rate X-band communications are still possible, they are
expected to deteriorate rapidly during the next 24 to 48 hours.  The loss of
reliable communications also makes it difficult for the navigation team to
obtain the doppler data necessary for precise calculations of the radar track.

     During Superior Conjunction the spacecraft engineers will have time to
analyze the solar panel oscillations and the possible tape recorder track
degradation.  By putting the spacecraft in a quiescent state while a
a good engineering telemetry margin still exists, the expected damping of the
vibrations can be observed.  It will also provide time for careful planning of
spacecraft command sequences when mapping is resumed.

     The mapping will resume in early to mid-November.  The portion of Venus
which is not imaged during this Superior Conjunction period will be covered
during the extended mission eight months from now.

     Stephen Saunders, the Project scientist for Magellan, provided images and
text for a special pictorial on Magellan to be published in the November
issue of Scientific American.  He also provided a special images for the covers
of the abstract volume of EOS.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

Date: 26 Oct 90 21:43:42 GMT
From: att!cbnewsl![e-mail]  (Stuart Warmink)
Subject: Re: Magellan Update - 10/26/90

>      A decision was made to suspend mapping at the end of orbit #676, 6:33 AM
> PDT on Friday, October 26.  The spacecraft stopped its mapping maneuvers, and
> will hold its position with the High Gain Antenna pointed to earth and the
> solar panels directed toward the sun.

As the Sun lies pretty much in between Magellan and Earth, won't the
dish antenna be rather effective at focussing the Sun's light and heat
at the secondary reflector and perhaps even the receiver/transmitter?
I guess it all depends on how good the dish's surface is at reflecting
those wavelenghts without scattering. Is the surface shiny?
--
------------------------------------------------------------------------------
Stuart Warmink, Whippany, NJ, USA  |  [e-mail]  |       Hi!
------------------------------------------------------------------------------

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

End of SPACE Digest V12 #498
*******************