Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_3/V13_320.TXT

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Date: Fri, 29 Mar 91 02:19:34 -0500 (EST)
Subject: SPACE Digest V13 #320

SPACE Digest                                     Volume 13 : Issue 320

Today's Topics:
       MAJOR GEOMAGNETIC STORM INFORMATION UPDATE #1 - 25 MARCH
            Re: Japan Moon Probes article
           Payload Summary for 03/25/91 (Forwarded)
        Small Comets (was: Re: NASA Headline News...)
          MAJOR SOLAR FLARE ALERT - 25 MARCH
            Re: Inter-probe communication

Administrivia:

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

Date: Sun, 24 Mar 91 23:56:08 MST
From: [e-mail] (CARY OLER)
Subject: MAJOR GEOMAGNETIC STORM INFORMATION UPDATE #1 - 25 MARCH
X-St-Vmsmail-To: st%"[e-mail]"

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

                       INFORMATIONAL MAGNETIC STORM UPDATE

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

                               06:30 UT, 25 March

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


STORM UPDATE INFORMATION:

     The geomagnetic storm continues in progress as of 06:30 UT on 25
March.  The middle-latitude magnetic A-index has been adjusted to correspond
with the storm start-time, and is now rated at 84.  This represents a moderate
to high intensity major geomagnetic storm.

     Severe middle latitude geomagnetic storming was observed between 20:30 UT
and 21:30 UT on 24 March, and again between 02:30 UT and 05:00 UT on 25 March.
Major storm levels have been observed since 20:00 UT on 24 March.  Storming is
expected to continue for the next 6 to 12 hours.  We should be just about
finished the main phase of the storm.  Post-storm activity will likely include
sporadic isolated substorming.  Localized magnetic activity could be fairly
intense until things stabilize later this UT day.

     Widespread low-latitude auroral activity is being reported throughout
most of the southeast U.S. tonight, despite the phase of the moon.  Auroral
activity will continue throughout most of the night for North American
observers.  Storm detensification is expected to occur later this UT day.
This is expected to be the last night for low-latitude auroral activity for
North American observers.  However, future major flaring could cause a
recurrence of low-latitude auroral activity this coming week.  Watch for
future major solar flare alerts and terrestrial impact assessments.

     Very intense ionospheric absorption during the afternoon hours over
North American middle and northerly middle latitudes produced a heavy HF
radio blackout on all HF bands.  Practically no communications were
possible until after sunset, when ionization detensified.  Near blackout
conditions were reported at several southern hemisphere locations as well
(ex. Australia).

     The satellite proton and PCA events have decayed over the past 24
hours.  A major solar flare, which occurred at 00:24 UT on 25 March may
further enhance the proton levels.  If this occurs, the Polar Cap
Absorption (PCA) event will likely continue for another 48 hours.  If no
protons are received, the PCA will likely end later this UT day.  This flare
has a modest probability for producing a minor geomagnetic and auroral
storm.  More will be known when additional data arrives regarding this event.
For more information, consult the Major Solar Flare Alert for 00:24 UT on
25 March.

Another informational update will be posted near 21:00 UT on 25 March.
Alerts and warnings will be updated and/or cancelled then.


The following alerts are IN PROGRESS:

   - MAJOR GEOMAGNETIC STORM ALERT
   - LOW LATITUDE AURORAL ACTIVITY ALERT
   - GEOMAGNETICALLY INDUCED CURRENT (GIC) ALERT
   - SATELLITE PROTON EVENT ALERT
   - POLAR CAP ABSORPTION EVENT ALERT
   - POLAR RADIO SIGNAL BLACKOUT ALERT


The following warnings remain in progress:

   - POTENTIAL MAJOR SOLAR FLARE ALERT
   - POTENTIAL PROTON FLARE ALERT


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

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

Date: 25 Mar 91 17:45:26 GMT
From: wuarchive!rex!rouge![e-mail]  (Fraering Philip)
Subject: Re: Japan Moon Probes article

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

>Absolutly, I agree.  After all, any country that can destroy America
>can go to any moon of their choice.  In case you hav'nt herd, America
>surrendered to Japan in Kuwait.  That was the main purpose of Foreign
>Minister Taro Nakayama to Washington, to remind the President that the
>U.S. in now owned by Japan and that Washington D.C. has been moved to
>Tokyo Japan.

1. If the Japanese were running the U.S., they'd do a better job. :-)

2. More likely, the U.S., if it surrendered to anyone, surrendered to
Kuwait. I was under the impression that the Japanese position on the
whole thing was "He can't drink his oil, he has to sell it to
someone..."

3. I've also heard the Japanese critisizing the U.S. for causing the
war by its great oil consumption, and because the U.S. does not
conserve. Although we get a lot less of our oil from the Persian Gulf
in the first place, they miss the point: all the U.S. has to do is to
deceide to stop hindering local production. Given the current state of
the U.S. oil industry, _and_ the U.S. nuclear industry (and as someone
who has gone through a lot because of the near collapse of the
former), I think a lot more U.S. energy policy issues are being
deceided in Riyadh than in Tokyo. I would like to point out that a lot
of the Japan bashing, such as you said your article could be
interpreted as (in your response?  please clarify what you meant
there...), serves mainly to divert interest away from the much more
dangerous influences of the much less democratic Middle Eastern
'allies' of the U.S., with whom, by the way, IMHO, the U.S. shares one
hell of a lot less 'common values' than with, say Japan.

3.(short form): U.S. bashing in Japan, and Japan bashing in the U.S.,
isn't constrctuve or accurate, and it probrably helps hide _real_
'foreign entanglements.'

4. You should be much more careful than you have in putting accross
your views. Were this a full moon, I'd have turned into a werewolf and
really flamed you. :-)

5. I doubt the Japanese have destroyed America. If America is found to
be dead one day, the coroner will probrably rule it a suicide. :-(

Phil Fraering
[e-mail]

And I don't know the _exact_ quote, but Malcolm X once said something
to the effect (and this is the spirit of what he wrote): "America's
biggest problem is its tendancy towards self-destruction."

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

Date: 25 Mar 91 20:46:51 GMT
From: [e-mail]  (Peter E. Yee)
Subject: Payload Summary for 03/25/91 (Forwarded)


                               PAYLOAD TEST AND ACTIVITY SHEET
                               Kennedy Space Center, Florida
                               March 25, 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
          Astronaut payload sharp edge inspection: 1/29
          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
          Astronaut payload bay sharp edge inspection: 3/19
          Interface Verification Test (IVT):  3/21



          ACTIVITY FORECAST   * Denotes Change

          GRO end-to-end test: 3/25
          Battery reconditioning: 3/25-30
          Final JIS-Nominal Day 3 deploy: 3/27
          GRO closeouts for flight: 4/1
          Close payload bay doors: 4/2

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

Date: Mon, 25 Mar 91 15:37:27 PST
From: [e-mail]
X-Vmsmail-To: UTADNX::UTSPAN::AMES::"[e-mail]"
Subject: Small Comets (was: Re: NASA Headline News...)


In SPACE Digest V13 #290,
zaphod.mps.ohio-state.edu!samsung!rex!rouge![e-mail]  (Fraering Philip) writes:

>In article <[e-mail]> [e-mail] (Ron Baalke) writes:

>>NASA has terminated the operation of the Dynamics Explorer-1
>>(DE-1) spacecraft.  The spacecraft, which acquired the first global
>>images of the aurora, was launched on August 3, 1981.

>Wasn't this the spacecraft whose data touched off (or helped touch off)
>the mini-comet controversy?

Dark pixels in the images from the DE-1 UV-imager were interpreted by some
as being due to water vapor clouds, which were in turn postulated to come
from small (12 meter diameter) comets (not mini-comets, another theory).

The most likely explanation of the dark pixels, which occur in the data at
the rate of about 1 per 800 pixels, is that they were simply instrument
artifacts.  Consider, for example, that the size of the darkened pixel areas
(actually single pixel events) does not change with Earth image size as the
spacecraft goes from 1100km to 23300km in its highly elliptical orbit.

However, since the spacecraft cannot be retrieved (without considerable
expense) the instrument artifact hypothesis can't be directly proven.  On
the other hand, the small comet hypothesis, which seems so attractive on
first hearing (else it never would have been published), crumbles upon
examination like the fluffy snowballs it puports to reveal.  Nevertheless,
the "controversy" does exist and persists almost soley on the strength of
the reputation of the small comets' main proponent.

>Speaking of which, I ask again: has there been any new evidence for or
>against the theory, such as Galileo was possibly (I'm not sure) supposed
>to gather?

The European Viking (pron. veeking) satellite with UV-imager produced no
supporting evidence for the small comet hypothesis.  The word on the
grapevine is that Galileo also produced no supporting evidence.

>Phil Fraering
>[e-mail]

_____________
Dale M. Greer, whose opinions are not to be confused with those of the
Center for Space Sciences, U.T. at Dallas, UTSPAN::UTADNX::UTDSSA::GREER
"I am not making this up." -- Lou Frank in _The Big Splash_

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

Date: Mon, 25 Mar 91 00:04:21 MST
From: [e-mail] (CARY OLER)
Subject: MAJOR SOLAR FLARE ALERT - 25 MARCH
X-St-Vmsmail-To: st%"[e-mail]"

                        --  MAJOR SOLAR FLARE ALERT  --

                                MARCH 25, 1991

                              Flare Event Summary
                           MODERATE IMPACTS POSSIBLE


                                    --------



MAJOR ENERGETIC EVENT SUMMARY

     Another major X-class flare erupted from Region 6555 early this UT
day.  The flare was not well covered by optical flare patrols.  Beginning
and end times are uncertain.  From the data received so far, the event
began sometime before 23:27 UT on 24 March, peaked near 00:19 UT and ended
sometime after 01:03 UT on 25 March.  The flare was rated a class X1.1/1B
event (although the optical rating is not yet definite) and was located at
S26E01.  The integrated x-ray flux was not particularly intense, but was
"moderate" nonetheless (rated at 0.110 Joules / meter^2).  Radio coverage
of this event was difficult, in part due to the intense magnetic storming
which was in progress at the time of this event.  However, there was an
unconfirmed report of a Type IV event.  This is not official yet.

     Region 6555 is now located at S24W11 and is maintaining a very potent
configuration.  It has high magnetic gradients, high amounts of shear and
is a Beta-Gamma-Delta magnetic configuration.  This region is expected to
continue to produce potentially significant major solar flares.  It is very
capable of producing strong terrestrial impacts if a particularly intense
flare occurs.


POTENTIAL TERRESTRIAL IMPACT ASSESSMENT

     This latest flare has a good possibility for producing a potentially
minor geomagnetic storm.  The flare probably won't be capable of producing
a storm as intense as the class X9.4/3B flare of 22 March (which we are
experiencing now), but a disturbance is possible.  The probabilty is rated
at near 50% for a minor geomagnetic storm.  Models suggest an estimated
magnetic planetary A-index of about 44 on 27 March if this flare produces a
terrestrial impact.  However, it should be noted that predicting
geomagnetic activity from major flares is a very difficult process with
fairly high failure rates, particularly with borderline flares as this one is.

     If protons become enhanced within the next six hours, a terrestrial
impact will be more likely.  Until this is known, the probability for
terrestrial impacts will remain at about 50%.  If terrestrial impacts do
materialize, they will likely begin near the middle to latter part of the
UT day on 26 March, with possible storm periods (mostly over the higher
latitudes) on 27 March.

     Solar protons have decayed substantially from yesterdays values.
Current proton levels are at near 250 pfu at greater than 10 MeV.  The
greater than 100 MeV protons have decayed to values near 4 pfu.  The PCA
absorption is currently running near 1.4 dB's, which is significantly
reduced over yesterdays values.  The PCA is expected to end within the next
24 hours, unless protons become enhanced from the recent major flare.  The
satellite proton event will likely endure for the next 48 hours, barring
any further major flaring.

     Major flaring is expected to continue out of Region 6555.  A high risk
exists for potential major proton flaring from this region.  It is in a
sensitive position for producing terrestrial impacts and will remain in
that position for the next three to four days.  Watch for possible future
flare alerts.

     For geomagnetic information, consult the recent Geomagnetic Storm
Informational Update #1 (06:00 UT, 25 March).  Radio propagation
information is also included therein together with the forecast conditions.


**  End of Alert  **

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

Date: 25 Mar 91 16:30:32 GMT
From: zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Inter-probe communication

In article <[e-mail]> [e-mail] (Perry Pederson) writes:
>... If something
>'went wrong' and a probe lost communications from Earth, could one
>spacecraft be given commands from Earth to redirect its radio dish and
>relay/forward commands to another probe that couldn't receive commands
>from Earth?

In general, this wouldn't be a useful thing to try.  The probes have,
relatively speaking, very small antennas and very low-power transmitters.
They maintain communication with Earth successfully only because the
Earth stations have very large antennas, very sensitive receivers, and
quite powerful transmitters.  Inter-probe communication is viable only
at (astronomically speaking) extremely short range.  This tactic would
be practical only if the two were already operating together, e.g. a Mars
orbiter relaying communications to a Mars lander, and it probably would
be useful only if the relaying would go through different equipment on
the troubled probe than direct signals would.
--
"[Some people] positively *wish* to     | Henry Spencer @ U of Toronto Zoology
believe ill of the modern world."-R.Peto|  [e-mail]  utzoo!henry

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

End of SPACE Digest V13 #320
*******************