Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v13_2/v13_287.txt

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Subject: SPACE Digest V13 #287

SPACE Digest                                     Volume 13 : Issue 287

Today's Topics:
       SOLAR TERRESTRIAL BULLETIN - WARNING UPDATES - 18 MARCH
             space news from Jan 28 AW&ST
       Re: Saturn V (was: space news from Jan 28 AW&ST)
            Re: Magellan Update - 03/13/91
            Re: Magellan Update - 03/11/91
Re: German conference highlights doubts about ESA's manned space plans
          Re: Government vs. Commercial R&D
        Re: Value per pound vs. cost per pound

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    Submissions to the SPACE Digest/sci.space should be mailed to
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Date:    Mon, 18 Mar 91 01:06:13 MST
From: [e-mail] (CARY OLER)
Subject: SOLAR TERRESTRIAL BULLETIN - WARNING UPDATES - 18 MARCH
X-St-Vmsmail-To: st%"[e-mail]"

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

                        SOLAR TERRESTRIAL BULLETIN

                              18 March, 1991

                  Terrestrial Geophysical Warning Updates

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


UPDATED WARNING INFORMATION

     A sudden magnetic impulse was observed at many middle latitude
magnetic observatories on 17 March.  The SI was not observed locally,
although Boulder and several other lower latitude stations reported a SI
measuring 12 gammas at 20:36 UT.  The cause of this impulse is believed to
be the major flare which occurred at 00:52 UT on 16 March.

     Geomagnetic activity has been generally quiet to unsettled since the
impulse, although it has increased very slightly since about 02:30 UT on 18
March.  Predictions call for possible minor storming over high latitudes,
while middle latitudes should remain generally unsettled to active.  No
storming is expected for the middle latitudes.

     The POTENTIAL GEOMAGNETIC STORM WARNING has been cancelled for the
middle latitudes.  No magnetic storming is expected in conjunction with the
major flare of 16 March.

     The warnings currently in progress follow:

  - POTENTIAL MAJOR SOLAR FLARE WARNING
  - POTENTIAL SATELLITE PROTON EVENT WARNING
  - POTENTIAL PCA ACTIVITY WARNING

     HF and VHF propagation should be normal to above normal over middle and
low latitudes.  A slight degradation in middle and high latitude signal paths
may be noticed on 18 March associated with the enhanced geomagnetic
activity.  However, no significant degradation is expected.  HF MUF's
should remain near 44 to 55 MHz (depending on location).  Openings on 6
meters remain possible.  A potential also exists for SID (Sudden
Ionospheric Disturbance) enhanced VHF communications.  The frequent number of
M-class flares and the potential for a major flare may provide conditions
favorable for SID-induced enhancements on VHF.  On the other hand, HF
operators will notice potentially frequent minor SWF's (Short Wave Fades)
during the daylight hours.


**  End of Bulletin  **

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

Date: 11 Mar 91 14:38:00 GMT
From: agate!linus!philabs!ttidca!quad1!bohica!mcws!p0.f851.n102.z1.fidonet.org![e-mail]  (Henry Spencer)
Subject: space news from Jan 28 AW&ST

From: [e-mail] (Henry Spencer)
Path: wciu!elroy.jpl.nasa.gov!decwrl!sun-barr!rutgers!news-server.csri.toronto.edu!utzoo!henry
Newsgroups: sci.space
Subject: space news from Jan 28 AW&ST
Message-ID: <[e-mail]>
Date: 11 Mar 91 06:38:45 GMT
Amroc proposes Aquila, a four-stage hybrid launcher for Motorola's Iridium
mini-comsat network, claiming 1500lbs to 300nmi at about half the cost of
current alternatives.

ESA declares Ulysses fully operational.

Space insurance rates expected to rise after circa $200M losses on recent
in-orbit satellite failures.

USAF Space Command has set up special data links to get data from missile-
warning satellites directly to Patriot batteries nearly in real time.
This plus other measures to improve communications have boosted warning
time for Scud attacks to nearly 5min from 90-120s.  Warning-satellite
officials say Iraq's Scud tests late last fall were serious blunders,
because they gave the US a priceless opportunity to debug the warning
setup before it was needed in combat.

Final design details have been settled for the field joint of the ASRM.
The new joints are bolted together, the O-rings remain visible as the
joint is mated, and the joint is designed to close up under pressure
rather than opening.  Looking at the diagram, inboard of the bolts the
joint is two flat flanges touching each other, and two O-rings are set
into the surface of the lower flange near the inner edge.  The upper
flange goes to the edge of the lower flange and then turns downward
around it, with a third O-ring set into the outer surface of this lip,
seating against the inner edge of the lower flange.

Another major ASRM design change is careful design of the internal shape
of the fuel so that thrust drops off somewhat for a brief period early
in the flight, eliminating the need for the SSMEs to throttle back during
the period of maximum dynamic pressure.  This eliminates assorted possible
failure modes related to throttle-back and the following throttle-up.
Other changes include a revised casing design that has fewer assembled
parts, one less field joint, welded factory joints, and better steel;
a simpler nozzle design eliminating assorted joints and seals; and a
redesigned igniter.  Finally, a lighter casing, a larger diameter holding
more fuel, and a slightly more energetic fuel give higher thrust, longer
burn, and about 18% more shuttle payload.  An important change unrelated
to the booster design is the shift to highly automated manufacturing,
since each handling step increases the odds of trouble.  [Another aspect
of this, not mentioned, is that the ASRM plant at Yellow Creek will be
NASA-owned, so NASA will be less tied to a single contractor and can
exert more control.]

ASRM still has its critics, however.  Some say the $971M would be better
spent elsewhere, especially on the SSMEs and on incremental improvements
to the existing boosters (since ASRM is still five years away).  There
is the possibility of political pressure to shift money to heavylift
boosters, and concerns about the environmental effects of the rather
"dirty" solid fuels.  Finally, there is still strong skepticism in some
areas about the safety of manned flight on solid boosters, given the
sensitivity to manufacturing flaws and the impossibility of test-firing.
Cost considerations are likely to preclude abandoning SRBs, however.

[That's it for space news in this AW&ST.  They are rather preoccupied
with other current events...  However, here's a *very* interesting bit
from the 15 Feb issue of Science:]

Congress is very interested in the Augustine commission's recommendation
for a heavylift launcher, and there is starting to be specific interest
in one particularly heavylift launcher... the Saturn V!!  Truly, questioned
about the matter, says the plans still exist.  It's pretty obvious, though,
that NASA would really prefer a shuttle-derived launcher.  Congress may
pursue the matter, although there is the obvious problem that tooling is
gone and many subcontractors are gone, so resurrecting the Saturn V would
be costly.
--
"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: 18 Mar 91 15:41:51 GMT
From: pilchuck!seahcx!phred![e-mail]  (Peter Jarvis)
Subject: Re: Saturn V (was: space news from Jan 28 AW&ST)

In article <[e-mail]> [e-mail] (John A. Weeks III) writes:
>
>I came to a personal conclusion that I could make or purchase any one of
>the parts, therefore I could build an entire Saturn V if I wanted to.
>.....the rest of the Saturn V is just a few large
>aluminum tanks with a few other parts (like engines) added on.
>Then it dawned on me that each of those parts were designed for a particular
>weight, strength, functionality, temperature range, vibration response, etc.
>
Yes there were a few other parts. The "brains" of the Saturn V were in the
guidance and control "ring" seated atop the 3rd stage. Around the inside of
this ring was alot of equipment, (power supplies, controllers, etc.).
You could duplicate the stuff, but it would be nice to have the schematics.

Peter Jarvis......

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

Date: 18 Mar 91 17:13:10 GMT
From: magnus.acs.ohio-state.edu!zaphod.mps.ohio-state.edu!sdd.hp.com!hp-pcd!hpcvca![e-mail]  (Ray Davis)
Subject: Re: Magellan Update - 03/13/91

>     The AACS (Attitude and Articulation Control Subsystem) Memory B readout
>tests were successfully completed yesterday and spacecraft controllers are
>continuing the process of loading Memory B today.  The upload of command
>sequence M1072, with its associated radar control parameter and mapping
>quaternion files was completed late yesterday and is executing properly.

. . . in other words JPL is getting their 'AACS' together ?


Please, no flames.

Ray Davis
_________________________________________
|  [e-mail]             |
|  [e-mail]        |
|  hplabs!hpcvca!rayd            |
|_______________________________________|

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

Date: 19 Mar 91 22:59:18 GMT
From: pacific.mps.ohio-state.edu!zaphod.mps.ohio-state.edu!rpi!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: Magellan Update - 03/11/91

In article <[e-mail]> [e-mail] (Ron Baalke) writes:
>>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 quickly we forget Surveyors 2 and 4.  Or were those not "really" JPL
failures because the birds were built by a contractor?

I was under the impression that Seasat was a JPL mission, although I can't
immediately find confirmation of this.

I also wouldn't count what happened to the Viking 1 lander as exactly a
shining example of JPL success.
--
"[Some people] positively *wish* to     | Henry Spencer @ U of Toronto Zoology
believe ill of the modern world."-R.Peto|  [e-mail]  utzoo!henry

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

Date: 11 Mar 91 16:56:26 GMT
From: news-server.csri.toronto.edu!utzoo![e-mail]  (Kieran A. Carroll)
Subject: Re: German conference highlights doubts about ESA's manned space plans

Nick Szabo [e-mail] write:
Subject: Re: German conference highlights doubts about ESA's manned space plans
Date: 8 Mar 91 01:53:56 GMT

> In article <[e-mail]>
> [e-mail] (Henry Spencer) writes:
>
> >Experience so far says very strongly that if you plan to do in-space repairs,
> >you had better plan to have humans (or the imaginary just-as-flexible
> >teleoperated robots which will be available almost right away now for sure,
> >really, trust us) on hand.
>
> Or, if you prefer not to pay the $1,000,000++/hour cost of an EVA, you
> could make sure it works before you launch it.

Nick, to ``make sure'' that a satellite ``works'' before you launch it,
you might have to spend anywhere from millions to tens of millions of
dollars, depending on the complexity of the spacecraft. What level of
reliability do you want to design into the satellite, and verify via
ground testing? 99%? Or three nines? Or four? Do you want dual-string
redundancy? Or are you going to make your designers hate you forever,
and insist on triple-string?

All those satellites that we've seen fail on orbit, including the ones that
the Shuttle was sent up to repair, were designed by people who tried
to ``make sure that it works'' befoire launch. Many of the people involved
in design of these are very smart, and very conscientious, probably more so
than you and I. Satellites don't typically fail because of sloppy design or
construction. They fail because >nobody< can imagine beforehand >all< the things
that might go wrong with a complicated, custom-built device.

My view is the cost of using spacecraft could be made cheaper if moderately-priced
on-orbit check-out and servicing facilities were available to be rented out.
That way, a great deal of the expense in designing spacecraft could be eliminated
(``the NASA way'' of design wouldn't have toof the expenses of ground-testing the beasts. However, this assumes that
you have >people< in orbit to do the testing and repair --- because the things that
will go wrong with your satellite will be exactly those that you didn't anticipate,
and so you won't have built your teleoperated robot to handle that
unexpected contingency, and so the robot won't be able to effect the repair.


--

     Kieran A. Carroll @ U of Toronto Aerospace Institute
     uunet!attcan!utzoo!kcarroll [e-mail]

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

Date: 11 Mar 91 09:54:00 GMT
From: sdd.hp.com!zaphod.mps.ohio-state.edu!think.com!linus!philabs!ttidca!quad1!bohica!mcws!p0.f851.n102.z1.fidonet.org![e-mail]  (Nick Szabo)
Subject: Re: Government vs. Commercial R&D

From: [e-mail] (Nick Szabo)
Path: wciu!elroy.jpl.nasa.gov!sdd.hp.com!spool.mu.edu!uunet!zephyr.ens.tek.com!tektronix!sequent!crg5!szabo
Newsgroups: sci.space
Subject: Re: Government vs. Commercial R&D
Message-ID: <[e-mail]>
Date: 11 Mar 91 01:54:32 GMT
In article <[e-mail]> [e-mail] (Paul Blase) writes:
>Maybe it is more
>subtle than I thought.  I was saying that for the most part, it is only
>the government that has the need and the money to fund the development
>                            ----         -----
>of the first useful product from advanced research, especially if that
>product is the first of its kind.

If understand your point, it is that government money is needed, not
necessarily government lab work.  The patent statistics and analysis
of major inventions show that industry does indeed develop first
products, sometimes with some government money, sometimes not, but nearly
always without government intervention in the design process.  More basic
scientific advances are usually the products of university and commercial
research labs, often with government funding but again with little
intervention in the technical specifications.


--
Nick Szabo            [e-mail]
"What are the _facts_, and to how many decimal places?"  -- RAH


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

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

Date: 14 Mar 91 00:34:00 GMT
From: agate!linus!philabs!ttidca!quad1!bohica!mcws!p0.f851.n102.z1.fidonet.org![e-mail]  (Glenn A. Serre)
Subject: Re: Value per pound vs. cost per pound

From: [e-mail] (Glenn A. Serre)
Path: wciu!elroy.jpl.nasa.gov!sdd.hp.com!spool.mu.edu!uunet!isis!isis!gaserre
Newsgroups: sci.space
Subject: Re: Value per pound vs. cost per pound
Message-ID: <[e-mail]>
Date: 13 Mar 91 16:34:47 GMT
I'd like to respond to Nick's responses, but I'm pressed for time and I'm not
absolutely sure I should be posting (rather tha emailing).   I'd appreciate
some feedback on this.  I might manage responses in a week or so.

What I'd really like to see discussed is Nick's contention that launch costs
for ELV's can't be reduced much below $5,000/lb because of limitations
intrinsinc (sp?) to Expendables (feel free to correct me if that's not what
you're saying, Nick :-).  What do people out there think the cost limiters
are?  It's certainly not fuel.
--

--Glenn Serre
[e-mail]
--

--Glenn Serre
[e-mail]


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

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

End of SPACE Digest V13 #287
*******************