Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v13_2/v13_292.txt

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Subject: SPACE Digest V13 #292

SPACE Digest                                     Volume 13 : Issue 292

Today's Topics:
               Re: space shuttle design
             space news from Feb 4 AW&ST
          MAJOR SOLAR FLARE ALERT - 19 MARCH
         Mini-Comet controversy - a new test

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Date: 12 Mar 91 02:24:00 GMT
From: sdd.hp.com!elroy.jpl.nasa.gov!swrinde!zaphod.mps.ohio-state.edu!think.com!linus!philabs!ttidca!quad1!bohica!mcws!p0.f851.n102.z1.fidonet.org![e-mail]  (Henry Spencer)
Subject: Re: space shuttle design

From: [e-mail] (Henry Spencer)
Path: wciu!elroy.jpl.nasa.gov!swrinde!zaphod.mps.ohio-state.edu!maverick.ksu.ksu.edu!rutgers!news-server.csri.toronto.edu!utzoo!henry
Newsgroups: sci.space
Subject: Re: space shuttle design
Message-ID: <[e-mail]>
Date: 11 Mar 91 18:24:17 GMT
In article <[e-mail]> [e-mail] (Paul Blase) writes:
>... Lubkin describes the findings of William McInnis,
>a "high-level engineer at Marshall", and Ali AbuTaha, who did a separate
>investigation of the disaster...
>Any comments?

McInnis I'm not familiar with, but AbuTaha is basically a crank.  He came
up with a steady series of offbeat theories about the Challenger failure,
some of which NASA took seriously enough to check (results negative).

There is really no need to invoke new failure mechanisms and sinister
coverups.  The Rogers Commission's account of the mechanism of the disaster
stands up quite well, is amply confirmed by the camera films and data, and
pointed to real and verifiable weaknesses in the design.  By far the
simplest explanation is that it happened exactly the way they said it did.
--
"But this *is* the simplified version   | Henry Spencer @ U of Toronto Zoology
for the general public."     -S. Harris |  [e-mail]  utzoo!henry


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

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

Date: 13 Mar 91 12:34:00 GMT
From: agate!linus!philabs!ttidca!quad1!bohica!mcws!p0.f851.n102.z1.fidonet.org![e-mail]  (Henry Spencer)
Subject: space news from Feb 4 AW&ST

From: [e-mail] (Henry Spencer)
Path: wciu!elroy.jpl.nasa.gov!usc!rutgers!news-server.csri.toronto.edu!utzoo!henry
Newsgroups: sci.space
Subject: space news from Feb 4 AW&ST
Message-ID: <[e-mail]>
Date: 13 Mar 91 04:34:42 GMT
[Another light week for the obvious reason.]

Discovery mission to fly in March [well, whenever...] to try out improved
shuttle computers:  more compact, lighter, less power, larger memory, and
higher speed.

Lockheed reveals project to develop three standard satellite buses, "F-Sat".
"F" officially is for "frugal", but it also stands for "fat", signifying use
of greater weight and power margins to minimize redesign for new payloads.
The F-Sats are meant for Atlas/Delta-class payloads, with a target cost
[not clear whether this is bus or whole bird] of $30M each.  [The list of
suggested applications is basically NASA and military, suggesting little
interest in commercial customers initially.]

USAF Space Systems Div. officially delays the next Navstar launch until
the solar-array pointing failure in the last Navstar is understood.

Cape York project hits a financial snag:  Essington Developments, the
project's current developer, is withdrawing and wants to sell out.

Discovery launch slips slightly due to defects in maneuvering thrusters.
[They haven't found the cracked door hinges yet.]

SDIO expects a strong shift in its funding, away from space-based hardware
towards ground-based hardware, in keeping with the new White House emphasis
on countering limited attacks.  Brilliant Pebbles is still hanging in there,
though, with SDIO bravely trying to prove that it could stop Scuds.

NASA tightens security, especially at KSC and JSC, as a precaution against
terrorism.  Most JSC tours have been suspended, and KSC tours are being
watched more carefully.  Employee entrances to crucial areas are also
getting more attention.

US Army's experimental Eris interceptor successfully sorts out an imitation
warhead from decoys and destroys it in test Jan 28.  Two more flight tests
are planned this year, aimed mostly at presenting more difficult problems
with decoys and countermeasures.

White House initiative to refocus SDI sparks Congressional debate, with
some claiming it revives the program while others claim it shows a program
still in search of a mission.

Spy satellite coverage of Gulf reported excellent, with frequent satellite
passes aided by the more modern birds' ability to work well to either side
of their ground track.  The Lacrosse radarsat is particularly useful in
spotting armored-vehicle concentrations in bad weather.  The missile-
warning satellites in Clarke orbit are proving to be somewhat useful
for reconnaissance as well; notably, the new-model warning sensors turn
out to be capable of spotting fighter afterburners, and use of this is
being studied.

[A sidelight on this is that the KH-12 that reportedly broke up after
shuttle launch last March appears to be operational; apparently the
"breakup" was jettisoning of covers and shields before maneuvering,
not an accident.]

Martin Marietta and Bechtel are scrambling to get pad 40 at the Cape
rebuilt in time for the Mars Observer launch in Sept 1992.  MO will go
up on Commercial Titan, but the main objective of rebuilding pads 40
and 41 is better Titan 4 facilities, to support the USAF's plans for
up to six launches a year.  Pad 40 rebuilding is particularly drastic,
with the old structure essentially being torn down and replaced in
its entirety.
--
"But this *is* the simplified version   | Henry Spencer @ U of Toronto Zoology
for the general public."     -S. Harris |  [e-mail]  utzoo!henry


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

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

Date:    Mon, 18 Mar 91 23:41:32 MST
From: [e-mail] (CARY OLER)
Subject: MAJOR SOLAR FLARE ALERT - 19 MARCH
X-St-Vmsmail-To: st%"[e-mail]"

                        --  MAJOR SOLAR FLARE ALERT  --

                                MARCH 19, 1991

                              Flare Event Summary
                          Potential Impact Assessment


                                    --------



MAJOR ENERGETIC EVENT SUMMARY

     Another major flare erupted from Region 6545 at 02:00 UT on 19 March.
This event began at 01:57 UT, peaked at 02:00 UT and ended at 03:37 UT on
19 March.  The event was associated with moderate intensity Type II and IV
sweeps, but was fairly impulsive.  The flare was rated a class M6.7/2B, but
was associated with a low integrated x-ray flux.  A 1,500 s.f.u. tenflare
accompanied this event, as did a 23,000 s.f.u. burst at 245 MHz.  The
estimated Type II velocity is around 600 km/s.  A SID/SWF also seems to
have been observed with this flare.


POTENTIAL TERRESTRIAL IMPACT ASSESSMENT

     No terrestrial impacts are expected from this flare, despite the fact
that it possessed Type II and IV sweeps.  The flare was actually quite
small.  The peak x-ray flux was of short duration.  No protons are expected
from this flare.

     Protons have decayed and are now below the 1 p.f.u. level.  However,
the warnings for proton and possible PCA activity remain in effect due to
the potential which exists for proton flaring from Region 6545.  This
region is continuing to decay, but will remain capable of producing major
flares for the next several days.

     A POTENTIAL PROTON FLARE WARNING IS NOW IN EFFECT.  Region 6545 is now
in a very capable position for producing terrestrial proton activity.  It
also has the capability of producing a proton flare.  Probabilities are
currently rated near 50%.  Polar regions should remain alert for possible
PCA activity and HF signal blackouts.

     Region 6555 (S22E67) is a very large and an apparently complex spot
group.  It also appears to be capable of producing major flares.  It is
believed this region could begin major flaring within the next two to five
days.  It is still too near to the eastern limb to discern any significant
detail.  More will be known over the coming days as this region rotates into
better view.

     From the detail that has been observed so far, it is apparent that this
region covers an area of 3,000 million square kilometers.  It currently
encompasses 22 visible spots (although many more are likely present) and is
classed as an FKI optical group.  Several large spots are visible in close
proximity to one another.  It also appears as though a fair amount of shear
exists in this system.  Additional bulletins will be posted regarding this
region over the next week.


**  End of Alert  **

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

Date: 19 Mar 91 21:15:14 GMT
From: agate!ucbast.berkeley.edu![e-mail]  (Stupendous Man)
Subject: Mini-Comet controversy - a new test

>>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?

  I'm not sure whether Explorer-1 was the satellite in question, but I can
add a new note to the mini-comet controversy.  I heard a talk by Robert
Mutel, U of Iowa, on March 1 in which he described an experiment which
is planned for this summer and might uncover new evidence for the
mini-comets (roughly ten-meter sized chunks of mostly ice which are
postulated to hit the Earth's upper atmosphere every few minutes).
He's planning to use a small telescope, equipped with a special
rapid-readout CCD chip, to take pictures of the entire face of the moon
every ten or twenty milliseconds for a number of weeks.  He's calculated
that IF the mini-comets exist in the numbers quoted by the original
discoverers, then roughly one per hour ought to hit somewhere on the visible
face of the moon.  Such an impact will produce a very short-lived burst of
light, from shock-heating of the ices in the comet.  He hopes to either
detect a large number of such events, confirming the theory, or by failing
to detect any, discredit it.

  I know it sounds a little strange (yes, I said "But why haven't such
flashes been seen by EVERYONE?", too), but I think that it's a pretty
reasonable experiment, and will certainly provide more proof, either way,
for the mini-comets than any of the claimed detections so far.

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

End of SPACE Digest V13 #292
*******************