Space & Astronomy/Space and Astronomy (October 1993).iso/pc/text/spacedig/v13_2/v13_260.txt

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Subject: SPACE Digest V13 #260

SPACE Digest                                     Volume 13 : Issue 260

Today's Topics:
Re: German conference highlights doubts about ESA's manned space plans
             Pioneer 10 Update - 03/08/91
              Re: Space Profits
           Re: Pioneer 11 Update - 03/01/91
    MEPCO '92: First Announcement of a unique conference!
        Re: Value per pound vs. cost per pound
           Re: Pioneer 11 Update - 03/01/91
Re: German conference highlights doubts about ESA's manned space plans
                  Re: Thrust

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
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----------------------------------------------------------------------

Date: 12 Mar 91 05:02:06 GMT
From: celit![e-mail]  (Dave Smith)
Subject: Re: German conference highlights doubts about ESA's manned space plans

In article <[e-mail]> [e-mail] (Nick Szabo) writes:
 >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.
 >

This is a screamer.  What do you do at Sequent, Nick?  Work in marketing?

--
David L. Smith
FPS Computing, San Diego        ucsd!celit!dave or [e-mail]
"It was time to stop playing games.  It was time to put on funny hats and
eat ice cream.  Froggie played his oboe" - Richard Scarry

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

Date: 12 Mar 91 00:41:06 GMT
From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Pioneer 10 Update - 03/08/91


                          PIONEER 10 STATUS REPORT
                               March 8, 1991

     For unknown reasons uncommanded changes have occurred on the Pioneer 10
spacecraft along with the non-execution of commands following a change to the
IDLE 2 CPA (Comand Processor Assembly) mode at the DSN (Deep Space Network).
This change, radiating continuous zeros in IDLE 2, was originally implemented
for Pioneer 11, and solved the frequent command rejects for Pioneer 11.  For
uniformity, this mode was also implemented for Pioneer 10 on February 28.

     Subsequent tracks on March 1 over Madrid and Canberra 70 meter antennas,
had receiver lock but could not lock up on the telemetry.  The stations
reported seeing 64 bits/second coded data in the SDA (Subcarrier Demodulator
Assembly), which was too high to achieve telemetry lock.  Bit rate change
commands were sent for 16 bits/second, and on March 2 good telemetry was
received from the 70 meter Madrid station.  Indications are that a number of
commands, including the IPP (Imaging Photopolarimeter) configuration commands,
had failed to execute, and that uncommanded changes has occurred.  On March 4,
the IDLE 2 mode was changed to the original one and zero non-radiating setting,
and no problems have been experienced since.  The connection between an idle
transmit pattern and an uncommanded change in the spacecraft is not yet
understood.

     On March 5, high winds at Goldstone caused a 1 hour and 22 minute loss of
telemetry.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|      Ron Baalke         | [e-mail]
     | | | |  __ \ /| | | |      Jet Propulsion Lab |
  ___| | | | |__) |/  | | |___   M/S 301-355        | Change is constant.
 /___| | | |  ___/    | |/__ /|  Pasadena, CA 91109 |
 |_____|/  |_|/       |_____|/                      |

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

Date: 11 Mar 91 01:37:45 GMT
From: zephyr.ens.tek.com!tektronix!sequent!crg5![e-mail]  (Nick Szabo)
Subject: Re: Space Profits

In article <[e-mail]> [e-mail] ("Allen W. Sherzer") writes:
>In article <[e-mail]>:
>
>[ Large infrastructure developed by private companies often with ]
>[ government subsidies, to one degree or another]

Some threads running through most or all of these items:

* the larger projects were based on many previous, smaller scale
  versions (railroads, canals, dams, roads, airplanes, etc. etc.)
* the actual design work was left to private industry
* the projects served well-defined markets (shipping, mail, power,
  etc.)
* the economic paybacks were large (compared to the money government put in)
* the government was interested because of national security reasons

In other words, while government helped pay for these, they worked
out the economic paybacks in the way a business would.  Both design
and operation were usually controlled outright by industry, though
in some cases (eg roads) these were contracted out.  All of them served
existing markets in a well-defined way (eg speeding up delivery of mail),
rather than developing new products.  In this way, infrastructure in
search of customers was largely avoided.

Current space infrastructure is being designed from scratch by
government agencies, with no economically scaled antecedents, and
with business analysis (if any) thrown in as an afterthought.  In large
part, that why it is failing.



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

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

Date: 11 Mar 91 12:04:44 GMT
From: mcsun!unido!mpirbn![e-mail]  (Daniel Fischer)
Subject: Re: Pioneer 11 Update - 03/01/91

In article <[e-mail]> [e-mail] (Ron Baalke) writes:
>     The IPP (Imaging Photopolarimeter) instrument will be turned on on
>the Pioneer 11 spacecraft on March 1 to allow it to warm up in preparation
>for another scan of Canopus on March 2...

Does this mean that Pioneer 11's RTGs are still powerful enough to support the
use of this instrument as it was used at Jupiter and Saturn? Could it be used
to (very slowly, of course), scan across the solar system and take another
shot of the kind Voyager 1 sent a year ago?

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

Date: 11 Mar 91 11:51:50 GMT
From: mcsun!unido!mpirbn![e-mail]  (Daniel Fischer)
Subject: MEPCO '92: First Announcement of a unique conference!


                           First Announcement

  MEETING OF EUROPEAN (AND INTERNATIONAL) PLANETARY AND COMETARY OBSERVERS

                             M E P C O '9 2

  in Violau, Bavaria, Germany, Europe, Earth, Sol, Milky Way, Local Cluster
     around the weekend of 7 June 1992, in the International Space Year

Since 10 years we, the Arbeitskreis Planetenbeobachter (Working Group of Plane=
tary Observers of Germany), arrange the Planeten- und Kometentagung (Meeting of
Planetary and Cometary Observers), which brings together more than 100 amateur
observers from German-speaking regions every year.

For the first time, in 1992 we want to invite planet and comet observers from
*all*over*Europe* and also the rest of the world, to open up new European and
international perpectives in amateur astronomy as well.

Languages will be English and German in parallel.

                               We offer:

# a unique meeting atmosphere in a beautiful landscape setting,

# conference, accomodation and catering in *one* building, the Bruder-Klaus-
  Heim with the famous Violau Observatory,

# papers and workshops for specific problems (i.e. planets etc.) and for
  bringing onwards contacts and collaboration across Europe and the planet,

# reports and exhibitions regarding the activities in the different countries,

# proceedings included in the fee,

# and an astro-geological excursion with scientific guidance.

The full fee for everything, including conference papers, accomodation, full
catering and the excursion will be only approx. DM 200,- (approx. $ 130,-).

           Details will be announced as they become available.
             The Executive Council MEPCO '92; 9 March 1991

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

The registration for this meeting will only start this summer, but nonetheless
it would be interesting for us to get a very rough idea of the possible
interest in different parts of the world. Whoever might have the slightest
thoughts of attending is kindly asked to send me a mail message, indicating
 # your country,
 # membership in a national astronomical society which might help us spreading
   the news (in case there is one),
 # and a probability rating of your attendance, ranging from 0 (certainly not)
   to 5 (absolutely sure you will come).

Many thanks! For the Exec.Counc.: Daniel Fischer = [e-mail]

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

Date: 11 Mar 91 02:28:16 GMT
From: zephyr.ens.tek.com!tektronix!sequent!crg5![e-mail]  (Nick Szabo)
Subject: Re: Value per pound vs. cost per pound

In article <[e-mail]> [e-mail] (Glenn A. Serre) writes:

>Nick:
>Name _one_ industry that successfully handles large, fragile,
>fuel-filled, use-once-and-throw-away objects at low costs.
>The military is the major field that does this, and the costs are
>not low.
>Me:
>The ELV industry?  ELVs aren't all that fragile, they don't get handled when
>their filled with fuel, and handling doesn't cost much time or money.

The original issue was, can chemical launch costs ever be significantly
lower than present, and if so, by how much?  Note that we need a factor of
10,000 drop to make manned flights to the Moon as economical as
a round trip to Tokyo.  This would be a change similar to going down
to the local Honda dealer and buying an Accord for a dollar bill and
change.

The point is, the ELV is _not_ low cost (at least not nearly as low cost
as we'd like it to be).  In large part, because of these characterestics
unique to and inherent in chemical rockets.

Commercial aircraft, for example, carry much less fuel per pound of
payload, travel much slower, and yet cost $millions to $hundreds of
millions apeice (compensated by reusing them 1000's of times).  It
seems both chemical airplanes and chemical rockets have flattened
out as far as cost/lb. is concerned.

Other factors, such as value/lb. and entry level costs can still be
dramatically improved, as demonstrated by Pegasus.  And of course,
there are many non-chemical-rocket options (gas gun, EML, laser
launch, tethers, etc.) that we should be working on.


>Customers do say:
>We want %100 reliability.

No, customers want a reliability level within the reasonable range
for a transportation system.  90-95% would be fine for freight, for
starters.  If you look at insurance rates, or work out customer costs
without insurance, you will see why.

>We want %100 launch availability

No, customers want availability within the reasonable range for a
transportation system, ie within minutes to weeks instead of delays
of months or years.  This is another strength of Pegasus -- it is the
first space transportation system that starts to understand what
transportation is all about.

>We want everything cleaned to clean room standards.

Since launch costs are otherwise so high, customers need to maximize
the capability of the payload.  Bring down the costs in other ways,
so payload value/mass ratio is not so important, and we can get rid
of the cleanroom.  This is not chicken/egg, since the cleanroom is only
a small part of the costs.

>We want to launch on need.

See comment on "100% launch availability".

>We want custom interfaces.

No, rocket makers want to make custom rockets with custom interfaces,
rather than building to fit existing payloads.  Actually, the fault lies
with both sides, and is well worth working on (cf. my "rocket clone" proposal).

>Etc. etc.
>Essentially, they _want_ to pay $5,000/lb

Essentially, space transportation customers want what every other
transportation customer wants (surprise!).  Chemical rockets seem
to be only capable of meeting these needs at a rate over
$5,000/lb.


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

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

Date: 11 Mar 91 15:44:38 GMT
From: mcsun!ukc!harrier.ukc.ac.uk![e-mail]  (S.S.Sturrock)
Subject: Re: Pioneer 11 Update - 03/01/91

In article <[e-mail]> [e-mail] (Daniel Fischer) writes:
>scan across the solar system and take another
>shot of the kind Voyager 1 sent a year ago?
                  ^^^^^^^^^^^^^^^^^^^^^^^^^

Missed that one, anyone know how I might get a look at it, or if not, at
least tell me what it showed?

Shane Sturrock, Biol Lab.  Canterbury, Kent, Great Britain.

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

Date: 11 Mar 91 21:45:08 GMT
From: news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: German conference highlights doubts about ESA's manned space plans

In article <[e-mail]> [e-mail] (Andreas G. Nowatzyk) writes:
>True, but I read the original argument slightly differently: It is possible
>to design Solar Max, etc. for in-orbit repair by robots, which was not done.

Actually, Solar Max is interesting because it *was* designed for in-orbit
repair, albeit by humans rather than robots... but in fact about half the
work the astronauts did on it was on subsystems which were not meant for
in-orbit repair!  This all boils down to trying to anticipate what might
fail, and as I said before, the unexpected is the real killer in these
things.

Some of the Hubble salvage schemes likewise involve in-orbit work on
subsystems that were not meant to be opened up in space; they are being
taken seriously with humans but probably couldn't be with robotics.

The Syncom repair was on things that weren't likely to fail in orbit
because they didn't have to work for any length of time, on a satellite
that wouldn't be repairable in orbit anyway because it would be out of reach.
Well, surprise surprise, the ignition control for the perigee motor *did*
fail, leaving the satellite crippled but within reach.  Ditto for the
upcoming Intelsat salvage mission.

And for both Solar Max and Palapa/Westar, a robotic repair mission would
have been a complete failure unless the hardware was very general-purpose,
because the custom-built grappling gadgetry simply did not work.  For
Solar Max, after some ill-advised initial fumbling, a procedure using
the shuttle arm proved workable, barely.  (I don't know for sure, but I'd
be surprised if it would have been practical with teleoperation delays.)
For P/W, there was a purely-manual backup procedure, which got used.
These experiences had sufficient impact that they didn't even bother with
the gadgetry for the Syncom repair, just let the humans do it.  (Note
that this required muscle, not just dexterity, to take the spin off the
bird by hand [!], and existing dextrous robots often are not muscular.)
--
"But this *is* the simplified version   | Henry Spencer @ U of Toronto Zoology
for the general public."     -S. Harris |  [e-mail]  utzoo!henry

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

Date: 11 Mar 91 03:20:23 GMT
From: zephyr.ens.tek.com!tektronix!sequent!crg5![e-mail]  (Nick Szabo)
Subject: Re: Thrust

In article <[e-mail]> [e-mail] (John Roberts) writes:
>Another method that has been mentioned is launching water from Earth, then
>using solar energy to convert it to hydrogen and oxygen for use in a
>conventional engine. Because of its greater density, the water should be
>much cheaper to launch than LOX/LH2.

Much cheaper, for high volumes, would be to capture a small burned-out
comet and launch low-mass mining and processing equipment (ice is much
easier to deal with than rock).   It would take two or three Delta
launches ($80-$120 million) to deliver 100 million kg into GEO
or higher orbit.  This gives us $1/kg plus the cost of upper stage,
retreival, and mining equipment.  Capture is accomplished via gravity
assist and/or aerobraking, with a small mass driver for fine-tuning.

The scientific and technological prerequisites are:

* We need to develop low-mass (<1 Delta payload) mining equipment that
  can operate in microgravity and vacuum to process methane and water
  ice with a small surface layer of tar, dust, and rock;
* We need to increase our tracking of near-earth asteroids from <0.1% to
  at least 10% of the c. 100,000 in the size range above 100m.

The water and methane can be moved to LEO, and used directly as reaction
mass for solar or nuclear thermal rockets.  The water can also be
electrolyzed into hydrogen and oxygen for use in chemical rockets.
These volatiles could also be used for life support, shielding, and
might provide raw materials for larger-scale space manufacturing.


>It might be possible to save even
>more money by using an exotic launch method such as linear or laser launch.
>(How 'bout that, Nick?)

This would be very valuable for cargo that cannot be easily mined
(all cargo for now). I urge NASA and government labs that want in on space
to get to work on advanced launch options.

Both of these cases provide clear examples of why both basic science
(in this case, astronomy) and advanced technology research are so
important to space development, and why setting narrowly defined
goals must be avoided.




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

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

End of SPACE Digest V13 #260
*******************