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Subject: SPACE Digest V13 #286

SPACE Digest                                     Volume 13 : Issue 286

Today's Topics:
              cause of shuttle disaster
            GRO Payload Sheet (Forwarded)
          Gailileo asteroid photo techniques
               Re: He3 on Moon?
               Re: He3 on Moon?
       SOLAR TERRESTRIAL BULLETIN - WARNING UPDATES - 16 MARCH
            Re: Magellan Update - 03/11/91

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

Date: 10 Mar 91 23:12:00 GMT
From: agate!linus!philabs!ttidca!quad1!bohica!mcws!p0.f851.n102.z1.fidonet.org![e-mail]  (Greg Roberts)
Subject: cause of shuttle disaster

From: [e-mail] (Greg Roberts)
Path: wciu!elroy.jpl.nasa.gov!usc!samsung!news.cs.indiana.edu!nstn.ns.ca!Iris1.UCIS.Dal.Ca!roberts
Newsgroups: sci.space
Subject: cause of shuttle disaster
Message-ID: <[e-mail]>
Date: 10 Mar 91 15:12:18 GMT
I have watched this thread of discussion about two 'high level' engineers
and their claim about the cause of the accident. I suggest that for anyone
interested in the facts, they obtain Volume 1 of the Presidential Commission
on the Space Shuttle Challenger accident, and look at the photographs on pages
22 - 36 and 74 - 81.
The strut failure is a nice theory, but has no photographic evidence to
support it. What the photographic (still and video) does support is exhaust
gas erosion of the ORing, which caused a hole in the SRB casing. This resulted
in hot exhaust gas burning the insulation on the ET, and causing a rupture.
It was the combustion of the contents of the ET causing the severe loading on
the shuttle. The strut broke because the lower attach point gave way from the
weakened ET causing it to rotate about the support.

I would like to see the 'evidence' cooked up by these two. Did they appear at
the Rogers Commission to testify? Do they have any materials testing reports,
independent photographic analysis, fatigue analysis or the like to support
their claim? Enquiring, although seriously skeptical minds, want to know.


--
: Greg Roberts - via FidoNet node 1:102/851 [phone]
: ARPA/INTERNET: [e-mail]
: UUCP: ...!{elroy!bohica,elroy!wciu,cit-vax!wciu}!mcws!851.0!Greg.Roberts
: Compu$erve: >internet:[e-mail]

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

Date: 18 Mar 91 23:39:15 GMT
From: agate!bionet!uwm.edu!zaphod.mps.ohio-state.edu!swrinde!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: GRO Payload Sheet (Forwarded)


                               PAYLOAD TEST AND ACTIVITY SHEET
                               Kennedy Space Center, Florida
                               March 18, 1991


          George Diller
          407/867-2468
          FTS 823-2468


          GAMMA RAY OBSERVATORY
          STS-37/Atlantis

          HISTORICAL ACTIVITY

          Arrival of Spacecraft at PHSF: 2/6/90
          First functional test begins: 2/26
          Install High Gain Antenna: 11/8
          Final functional test complete: 12/4/90
          Spacecraft Fueling complete: 1/11/91
          Install Flight Batteries: 1/15
          First Joint Integrated Simulation (JIS): 1/16
          Airborne Electrical Support Equipment (AESE) arrives: 1/24
          Install orbiter Airborne Electrical Support Equipment (AESE): 2/1
          Transfer GRO to Vertical Processing Facility: 2/7
          Installation into west test cell: 2/9
          VPF Standalone Functional Test: 2/12-13
          Interface Verification Test (IVT) of AESE: 2/17
          IVT of GRO (orbiter interfaces simulated): 2/23
          End-to-End (ETE) communications test (MILA/GSFC/TDRS): 2/25
          Payload Readiness Review: 2/25
          MILA RF communications test: 3/4
          Transfer payload to canister: 3/11
          Roll to Pad 39-B/Transfer to PCR: 3/13
          Initial GRO Battery Charging: 3/13
          Payload installation into Atlantis: 3/17


          ACTIVITY FORECAST   * Denotes Change

          TCDT: 3/19-20
          Astronaut payload bay walk down:  3/19
          Interface Verification Test: 3/21
          Launch Readiness Review: 3/21
          GRO/orbiter end-to-end test: 3/25
          Battery reconditioning: 3/25-30
          Final JIS-Day 3 deploy: 3/27
          GRO Flight Closeout operations: 4/1
          Close payload bay doors: 4/2

      ___    _____     ___
     /_ /|  /____/ \  /_ /|      Ron Baalke         | [e-mail]
     | | | |  __ \ /| | | |      Jet Propulsion Lab |
  ___| | | | |__) |/  | | |___   M/S 301-355        | Change is constant.
 /___| | | |  ___/    | |/__ /|  Pasadena, CA 91109 |
 |_____|/  |_|/       |_____|/                      |

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

Date: 19 Mar 91 17:58:57 GMT
From: borg!vangogh![e-mail]  (Jonathan Leech)
Subject: Gailileo asteroid photo techniques

In article <[e-mail]>, [e-mail] (Magnus Olsson) writes:
|> How "close" is 1000 miles in this context - i.e. what kind of resolution will
|> the images have? Will they be comparable ith e.g. Voyager's pictures of
|> Miranda?

    Which leads me to wonder: is the ``exposure time'' for the Galileo
CCDs much shorter than the Voyager vidicons?  Either way, will the
Target Motion Compensation technique developed for Voyager be useful
when zipping by such a close target?
--
    Jon Leech ([e-mail])    __@/
    ``God is more interested in your future and your relationships
      than you are.'' - Billy Graham

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

Date: 19 Mar 91 18:34:38 GMT
From: rex!samsung!usc!jarthur!nntp-server.caltech.edu!iago.caltech.edu![e-mail]  (Horowitz, Irwin Kenneth)
Subject: Re: He3 on Moon?

In article <[e-mail]>, [e-mail] (Jon J Thaler) writes...
>In article <[e-mail]>,
>Horowitz,[e-mail] (Horowitz, Irwin Kenneth)
>says:
>>It is left as an exercise for the reader to estimate the total mass of He3
>>that would be on the lunar surface...:-).
>
>I'd like to do that exercise, but I don't know:
>1: The flux of He3 in the solar wind,
>2: The residence time for He3 in the lunar soil.
>
>Please supply us eager NetNews fans with these numbers.
When I said it was left as an exercise for the reader, I meant it was left as
an exercise for the reader.  Get up from that computer terminal and walk to
the local science library (or better yet, an astronomy library) and look up
those values for yourself! :-)  Shouldn't be too difficult...just need the
total flux of the solar wind, and the percentage of He3 in the solar wind.
As for the "lifetime" of He3 in the lunar soil, I can't think of any loss
mechanisms that would necessarily apply (except perhaps evaporation and
thermal escape from the "lunar atmosphere").  He3 is a stable isotope, so
it won't decay radioactively.
-------------------------------------------------------------------------------
Irwin Horowitz                        |"Suppose they went nowhere?"-McCoy
Astronomy Department                  |"Then this will be your big chance
California Institute of Technology    | to get away from it all!"-Kirk
[e-mail]               |       from STII:TWOK
[e-mail]                 |
-------------------------------------------------------------------------------

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

Date: 20 Mar 91 04:05:45 GMT
From: usc!rpi!zaphod.mps.ohio-state.edu!ub!uhura.cc.rochester.edu!rochester![e-mail]  (Paul Dietz)
Subject: Re: He3 on Moon?

In article <[e-mail]> [e-mail] (Jon J Thaler) writes:

>That's the crux of the problem.  Since the He3 in the solar wind will only
>penetrate a few microns into the lunar surface, it is probably going to
>escape (due to thermal effects) very quickly.  Thus, I'd expect only
>microscopic amounts of He3 to be present at any time.  (It sounds to me like
>you don't know the answer either...)

Also, bombardment of the lunar surface will periodically bury some
regolith particles and expose fresh ones.

The Apollo program got measurements of helium in the lunar regolith.
Here are some numbers for helium-4 abundance, in ppm:

       Mission    Regolith Type     Helium-4
    ------------------------------------------------------
       A-11         High Ti Mare     60 ppm
       A-17         High Ti Mare      36 ppm
       A-12         Low Ti Mare      10 ppm
       A-15         Low Ti Mare       8 ppm
       A-16         Highland       6 ppm
       A-14         Basin ejecta       8 ppm

I understand the high concentration of helium in the high-Ti mare is
due to the high abundance of solar wind helium in ilmenite, FeTiO3, a
mineral which apparently readily traps volatiles.  This ore has also
been discussed as a source of oxygen, since when heated with hydrogen
it reacts to form water, iron and titanium dioxide (the water being
electrolysed to recover the hydrogen).

I assume helium-3 is mixed with helium-4 at the normal solar ratio.  I
can imagine, however, that local magnetic fields on the lunar surface
may have, over the eons, led to some variations in local isotope
ratios.  I understand some features in Lunar Orbiter photos of the
lunar surface have been interpreted as patterns formed by variations
in solar wind weathering caused by local magnetic shielding.

    Paul F. Dietz
    [e-mail]

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

Date:    Sat, 16 Mar 91 12:00:39 MST
From: [e-mail] (CARY OLER)
Subject: SOLAR TERRESTRIAL BULLETIN - WARNING UPDATES - 16 MARCH
X-St-Vmsmail-To: st%"[e-mail]"

                /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\

                        SOLAR TERRESTRIAL BULLETIN

                              16 March, 1991

                  Solar Information and Warning Updates

                /\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\


UPDATED WARNING INFORMATION

     An interplanetary shock has not yet arrived as of 18:00 UT on 16 March.
It is odd that a shock has not yet been observed and is causing conflicting
views on whether or not we might still see storming.  It is quite possible
this shock could still impact with the earth anytime over the next 24
hours.  However, as time passes by, the probability for any significant
storming is decreasing.  The SESC has dropped their storm warnings but do
not deny that the potential still exists for storming if a shock arrives.
On the other hand, the U.S. Air Force still have their warning flags up.
So there is uncertainty regarding the state of affairs over the next 24
hours.  A shock should have been observed over 24 hours ago.

     We still believe there is a fair possibility that an interplanetary
shock could impact with the earth on 16 or early on 17 March.  However,
there is also a good possibility that the sun-earth trajectory of the mass
ejection was simply not in a good position and may have missed the earth
altogether.

     All things being considered, we will maintain our POTENTIAL
GEOMAGNETIC STORM WARNING for the next 12 hours.  If nothing materializes
by 06:00 UT on 17 March, the warning will probably be terminated for this
earlier flare event.  If a shock does arrive, storming probably will not be
nearly as intense as was previously forecasted.  Hence, we are cancelling
the POTENTIAL GEOMAGNETIC INDUCTION WARNING effective immediately.  Also,
we are cancelling the POTENTIAL LOW LATITUDE AURORAL ACTIVITY WARNING since
the window for very significant activity has passed.  However, if a shock
arrives and conditions are particularly powerful thereafter, this warning
could possibly be reinstated.  For auroral observers, it wouldn't hurt to
take a peak on the evening of 16 March (local time).

     A POTENTIAL SATELLITE PROTON EVENT WARNING continues in progress at
the present time.  Also, a POTENTIAL PCA ACTIVITY WARNING remains in
progress.  Protons could easily surpass event thresholds with a powerful
proton flare from Region 6545 (which is now on the central meridian).  A
proton enhancement continues in progress.

     Geomagnetic activity could still reach moderate intensity minor storm
levels, giving possibly moderate to high auroral activity over the northern
middle and high latitude regions.  However, no significant southward
migration of the auroral zone is expected given the recent events (or lack of
events).  Geomagnetic activity at the present time (over middle latitudes) is
very quiet.  Abnormally quiet, in fact.  No auroral activity was visible on the
evening of 16 March.


SOLAR ACTIVITY INFORMATION UPDATE

     Region 6545 continues to be a threat.  It continues to sport a
magnetic beta-gamma-delta configuration and has a fairly significant amount
of shear in the main spot complex.  It has grown over the past 24 hours and
appears to be slightly more complex than it has been in the past.
Continued major flaring from this region is expected.  However, judging by
its past history, the majority of the major flares will probably be of
relatively short duration, but could include significant radio emissions
and produce intensive short-duration SIDs/SWFs.

     Further analysis has been performed on the most recent X-class flare
originating from Region 6545 (at 00:52 UT on 16 March).  Again, there are
conflicting views regarding the potential impacts of this latest flare.  It
had most of the ingredients and emissions characteristic of flare-induced
terrestrial impacts.  However, the problem arises when its past history is
considered.  It has produced strong Type II and IV flares previously that
(in most other cases) would have produced moderate to strong intensity
terrestrial impacts.  However, nothing has yet been observed.  Also, the
duration of the flaring has been unusually short for the x-ray intensities
that have been achieved.  We know that Pioneer Venus was struck with an
interplanetary shock and experienced some significant space environment
conditions which could have produced major storming had it occurred near
the earth environment.  But we have not yet observed any of the conditions
which that satellite apparently experienced.

     It is entirely possible that the entire problem has simply been a
positional one.  No one can say for certain.  If that has been the problem,
there is a much better probability that we could see an interplanetary
shock associated with the 00:52 UT flare event occurring late on 17 March
or on 18 March sometime, followed by possible minor storming shortly
thereafter.  A potential geomagnetic storm warning may be issued for 17/18
March if a better consensus can be achieved regarding possible impacts.  It
should be noted that the majority of flares accompanied by strong Type II
and IV sweeps have resulted in magnetic storming when well placed as this
latest flare was.  But again, uncertainty exists because previous major
flaring from this region SHOULD have produced impacts, but hasn't (yet).
The short duration of the flare event is also of concern in this regard.

     To summarize, the POTENTIAL GEOMAGNETIC STORM WARNING is being
continued for the next 12 hours. The POTENTIAL SATELLITE PROTON EVENT WARNING
is being continued.  The POTENTIAL PCA ACTIVITY WARNING is also being
continued.  And finally, the POTENTIAL MAJOR SOLAR FLARE WARNING remains
in effect.

     The POTENTIAL GEOMAGNETIC INDUCTION WARNING has been cancelled.  Also,
the LOW LATITUDE AURORAL ACTIVITY WARNING has been cancelled for now.

     A re-evaluation of the Potential Geomagnetic Storm Warning will be posted
around 06:00 UT on 17 March.


**  End of Bulletin  **

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

Date: 17 Mar 91 23:57:08 GMT
From: pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!swrinde!elroy.jpl.nasa.gov!freedom!xanth![e-mail]  (Jonathan McDowell)
Subject: Re: Magellan Update - 03/11/91

[e-mail] (Ron Baalke) writes:
>In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>>In article <[e-mail]> [e-mail] (John A. Weeks III) writes:
>>>... As always, the brilliant people
>>>at JPL and NASA have found ways to keep Magellan running while maximizing
>>>the amount of data collected.
>>Well, be honest:  "as usual", not "as always".  JPL has had failures.
>This is true, but the last one was in 1964 with Ranger 6.

How about Mariner 8 in 1971? OK, so the failure wasnt JPL's fault,
and it may be unreasonable to expect
you to collect *too* much Mars data from the bottom of the Atlantic...

Just quibbling, of course. JPL have an amazing record and I'm sure it
will continue. I'm already getting excited about waiting for the
Cassini/Huygens results to come out.. :-)

 - Jonathan

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

End of SPACE Digest V13 #286
*******************