Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V13_6/V13_682.TXT

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Subject: SPACE Digest V13 #682

SPACE Digest                                     Volume 13 : Issue 682

Today's Topics:
         Re: Self-sustaining infrastructures
               Re: More on Freedom Vote
Re: The Reasons for a Station? Was Re: Rational next station design...
               Re: satellite refuelling
          USA Environment Protection Agency
         Re: Self-sustaining infrastructures
         Re: Self-sustaining infrastructures
         Re: Moonbase movie *Plymouth* to air Sunday?
         Re: Self-sustaining infrastructures

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Date: 2 Jun 91 00:53:30 GMT
From: van-bc!rsoft!mindlink![e-mail]  (Nick Janow)
Subject: Re: Self-sustaining infrastructures

[e-mail] (Allen W. Sherzer) writes:

> So far all the robotic attempts to repair have failed. The Solar Max repair
> would have failed had there not been humans on hand.

Yes, that's true.  Since our robotics technology isn't advanced enough for such
tasks yet, maybe it would be a good idea to fund further R&D so that it will be
possible.

> I never said there would be no robotics on this station. When you and Mr.
> Szabo are willing to let nurses stick needles in your arms by tele- operation
> we can talk.

If the government chooses to fund manned space projects instead of robotics and
related technologies, it's going to be a long, expensive wait.  Of course, the
Sanyo pocket med unit might be on the market while space station Fred is going
through its 500th redesign.  :-/

>+ A human may be more versatile than a robot, but a robotics service can be
>+ more economically versatile than humans.
>
> Depends. I myself don't think that the drawings can be kept accurate enough
> for robots.

That's why work has to be done on adaptive systems, which can adapt to
unexpected conditions or recognize them and ask for further instructions.  If a
company hires the repair service to replace module a-458 and gives them old,
incorrect information, that's the company's fault.  Even a human repair
technician would have to call back for correct information.

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

Date: 3 Jun 91 20:20:52 GMT
From: mojo![e-mail]  (Doug Mohney)
Subject: Re: More on Freedom Vote

In article <[e-mail]>, [e-mail] (Allen W. Sherzer) writes:
>They are coming out of the woodwork to get funding for Freedom. McDonnell
>Douglas has been putting large ads in Roll Call (the House newspaper) and
>the Washington Times. Rockwell and Boeing are also lobbying big time and
>it seems to be working.

>conservative. If the full house voted today, Freedom would receive
>full funding.
>
>Another interesting note is that the President is playing hardball on
>this issue. He recently spoke with Jamie Whitten who is the head of
>the Appropriation Committee. He told him that if Freedom isn't built
>then there was no reason to build the Advanced Solid Rocket Motor (ASRM)
>for the Shuttle. ASRM is built in Whitten's district and he consideres
>it an important project. Bush's veiled threat should have a big effect.
>

And you are so naieve as to think that you can get Congress to kill the
Shuttle, which is already operational, to go to tin cans....

Watch, look, and learn.


     Signature envy: quality of some people to put 24+ lines in their .sigs
  -- >                  [e-mail]                        < --

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

Date: 3 Jun 91 01:57:23 GMT
From: spool.mu.edu!agate!earthquake.Berkeley.EDU![e-mail]  (George William Herbert)
Subject: Re: The Reasons for a Station? Was Re: Rational next station design...

In article <[e-mail]> [e-mail] (Daniel Fischer) writes:
>>    * Long-term Human studies
>This kind of study is being performed by the Soviets since two decades; they
>have had people up for 1 year and flown a doctor on a 200+ days mission. What
>could be learned by repeating these boring adventures that they don't already
>know and are likely ready to join?

    While you're confident that the Soviets have learned all we have to
about people in space, I'm not.
    First: they have very little nonintrusive biomonitoring equipment.
Having looked over some of the data they have on their cosmonauts, it's
pretty obvious that their data is rough and incomplete.  Not only that,
but it's not continuous... it's seperate point samples weeks apart, often.
The US has continuous data on subjects... for a period of a week.  We need
detailed long-term studies...and the soviet work so far doesn't go very
far.

>>    * some Microgravity (not all)
>Microgravity reasearchers prefer quick return of their samples and do *not* ask
>for superduper manned stations that can be served only once in a while.

    Depends on what researcher.  I've heard several ask for manned
assistance... (though also many who wanted none, and some that wanted
ten-year experiments...)

>>    * most Biological science
>What Biological science? Again the Soviets have done all that before,especially
>with the Biosputnik spacecraft where many foreign experiments were flown.
>Adding up points 1 & 3 one could also ask: why should we be interested at all
>in the response of biological systems to microgravity as all life as we know it
>has developed under 1g conditions? Seems like a lousy circular argument: "We
>need man/animals in space so that we can learn how badly space affects them..."

    Again, the depth and accuracy of the Soviet research are not
sufficient.

-george william herbert
[e-mail]

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

Date: 2 Jun 91 15:46:14 GMT
From: mintaka!think.com!zaphod.mps.ohio-state.edu!caen!ox.com!hela![e-mail]  (Allen W. Sherzer)
Subject: Re: satellite refuelling

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

>Or, if I phrase that differently, without the Kelly act (and other
>aviation related legislation and regulation) we might have a more
>advanced aerospace industry than what we currently have.

Always possible but it doesn't seem likely. Before the laws and policies which
make up the Kelly Act there where lots of attempts at airlines which failed.
There wasn't enough of a market for people to build airports so most where
restricted to taking off on water (like the Maimi to Havana route). The
hardware just wasn't reliable enough (80% of the original air mail pilots
where dead within the first six years). I can't imagine a scenario where
this evolves into a modern airline without the Kelly Act. At best we
might find ourselves today with service like we had in the early 30's.

>But how could you verify something like this?

You can't. All we can do is to see that this policy used market forces
to reduce costs using subsidies and that it worked. It may or may not
have worked as well as no Kelly Act but it did work. Today we are faced
with a similar situation regarding space. IMHO we should have a Kelly
Space Act to do the same thing for the simple reason that we have seen
it work before.

  Allen

--
+---------------------------------------------------------------------------+
|Allen W. Sherzer |   DETROIT: Where the weak are killed and eaten.         |
|   [e-mail]   |                                                         |
+---------------------------------------------------------------------------+

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

Date: 3 Jun 91 09:49:05 GMT
From: mintaka!think.com!samsung!munnari.oz.au!bunyip.cc.uq.oz.au!marlin.jcu.edu.au![e-mail]  (Lee Askew)
Subject: USA Environment Protection Agency


Hello,
    I'm not sure if this is the correct group to ask for the
information below, but here goes.

I would like to know if anyone in the USA has any information on the
US Environment Protection Agency specifically information on Priority
Pollutents, and their level in syrum if possible.

I believe from my research here that there are between 20 to 30 of them.

If anyone has ANY information on the priority pollutents, I would be
very much grateful for the information..

Thanks Alot..
Lee.



  Regards, Lee Askew    Internet:[e-mail]
                        X25:27372000051::L_ASKEw
  Phone: [phone]  Snail: Computer Centre
  Fax:   [phone]         James Cook University
                               Townsville, 4811
                     QLD, Australia

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

Date: 3 Jun 91 14:30:19 GMT
From: agate!bionet!uwm.edu!zaphod.mps.ohio-state.edu!sol.ctr.columbia.edu!emory!wa4mei!ke4zv![e-mail]  (Gary Coffman)
Subject: Re: Self-sustaining infrastructures

In article <[e-mail]> [e-mail] writes:
>In article <[e-mail]> [e-mail] (Frank Crary) writes:
>
>>For a 2-man station, of a soviet Mir-type, able to maintain/refuel/repair
>>50 satellites / year, the OMV to move the satellites around, and the logistical
>>support of this system...
>>
>>approximately $ 5,000 Million to develop/launch
>>        1,500 Million per year to support
>
>
>>This comes to $30 million per satellite repaired.
>
>
>This is stupendously wrong.

While I don't think in space servicing is quite cost effective yet,
your arguments are seriously off base.

>* The best cost estimate for a four-man station is $120,000 million
>  (GAO). It is unknown what Mir costs.  A two man station requires the same
>  life support, refuelling, etc. equipment R&D and would not, I think,
>  cost significantly less than a 4-man job.

The GAO estimate is the 30 year life-cycle cost of Fred, not the construction
and launch cost. You are comparing apples and oranges here. A couple of
tin cans, a Mir like station, would have considerably less construction and
launch cost, probably less than Skylab. Using Progress style automated
freighters to service the station reduces it's operating costs remarkably.
Using Frank's numbers as a base, and converting them into GAO style life
cycle costing, the satellite service station has a life cycle cost of $50
billion dollars. Because more than $40 billion of Fred's costs are up
front, and most of space station Frank's costs are distributed over it's
lifetime, it looks even better.

>* The number of satellites launched into any particular low earth orbit
>  reachable by an OMV is less than 5/year, not 50/year.  The number of
>  those actually benefiting from refueling is probably no more than one per
>  year; other satellites can be redesigned for optimum component/fuel
>  lifetime balance for less than $30 million.

Servicing only the satellites launched in a given year is not necessarily
the design goal of this service station. Satellites break on irregular
schedules. Satellites use different amounts of station keeping fuel
depending on their design and mission. And satellites may require servicing
more than once during their life cycle. If we assume that communications
satellite technology is reaching maturity, a reasonable assumption. Then
satellites designed for twenty year life cycles with yearly service calls
become reasonable. With the assurance of on orbit servicing, many of the
design decisions on satellite construction would be altered. Instead of
the present throwaway design, satellites designed for long life cycles
and periodic maintenance, similar to earthbound telco central office
design, would become attractive.

>* You didn't even bother to amortize the $5 billion.
>
>
>Over 30 years at 10%/year, this comes to $7,800 million per repair,
>about 6 times the cost of launching a brand new Hubble telescope,
>and 160 times the cost of making the largest launcher upgrade
>that could conceivably be needed (Titan 3 to Titan IV, c. $50 million)
>to add fuel to a large commercial satellite.

$5 billion amortized over thirty years at 10%/year comes to $87.2 billion
dollars. Spread over 50 satellite service calls a year for thirty years,
that comes to $58.1 million per service call. That doesn't include station
operational and resupply costs. Assume eight Progress style resupply
and crew rotation flights a year at $100 million each. That comes to
an additional $16 million for each of 50 satellites serviced per year.
So we now have $74.1 million per service call. This is approaching the
throwaway cost of current design satellites. If we take Frank's higher
$1.5 billion a year support number, we get $30 million per satellite,
so the total cost is now $88.1 million to service a satellite. With new
higher capacity satellites designed for long service life with routine
servicing, this may be a reasonable number.

If the station can be justified on other grounds, the amortized cost
can be discarded and servicing costs reduce to less than $16 to $30 million
per satellite. *That* figure is justified even with current style
satellites.

Gary

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

Date: 3 Jun 91 19:25:06 GMT
From: swrinde!zaphod.mps.ohio-state.edu!rpi!crdgw1!gecrdvm1![e-mail]
Subject: Re: Self-sustaining infrastructures

In article <[e-mail]>, [e-mail] (Gary Coffman) says:
>
>
>>* The number of satellites launched into any particular low earth orbit
>>  reachable by an OMV is less than 5/year, not 50/year.  The number of
>>  those actually benefiting from refueling is probably no more than one per
>>  year; other satellites can be redesigned for optimum component/fuel
>>  lifetime balance for less than $30 million.
>
>Servicing only the satellites launched in a given year is not necessarily
>the design goal of this service station. Satellites break on irregular
>schedules. Satellites use different amounts of station keeping fuel
>depending on their design and mission. And satellites may require servicing
>more than once during their life cycle. If we assume that communications
>satellite technology is reaching maturity, a reasonable assumption. Then
>satellites designed for twenty year life cycles with yearly service calls
>become reasonable. With the assurance of on orbit servicing, many of the
>design decisions on satellite construction would be altered. Instead of
>the present throwaway design, satellites designed for long life cycles
>and periodic maintenance, similar to earthbound telco central office
>design, would become attractive.
>
>Gary
Ok, here's a thought that if it pans out guarantees funding (but since
it's probably off base, no bets please).  Simply say that refueling
sats is for reasons of "national security".  Realising that most (?)
military spy sats are in geo orbit and unreachable by OMV, what if some
were put in low orbit and designed to be highly mobile?  this mobility
eats up fuel right, and is the reason we don't move them around at whim
(maybe to check out what's over yonder border just for the heck of it)?
If we could refuel them easily, might not such a sat find some kind of
useful niche?  Adding the "national security" moniker makes it easier to
get funding, since we already waste billions (trillions?) on such
scams, er, schemes.  Of course, adding the "NS" moniker also raises
the likelihood that any such refueling capability get labeled "top
secret" and thus unavailable for the commercial world.  Any comments?
Pete

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

Date: 3 Jun 91 20:36:31 GMT
From: agate!earthquake.Berkeley.EDU![e-mail]  (Frank Crary)
Subject: Re: Moonbase movie *Plymouth* to air Sunday?

In article <[e-mail]> [e-mail] (Gary Coffman) writes:
>The one thing that fasinated me was the way they attempted to get around
>the "moonwalk" problem. In a TV show, especially one with a large cast,
>the problem of simulating a walking gait other than Earth normal is
>horrendous.

 Actually, the odd way the Apollo astronauts was NOT exactly a result of
the low Lunar gravity. At least in part, it resulted from the spacesuit
design: The Apollo suits had both poor lower body/leg mobility AND a
heavy (equivilent to 17 kg on Earth) portable life support system/
backpack. The PLSS backpack rode high on the astronaut's back, and there
was no balancing weight in front. The result was that the astronaut's
center of mass was shifted far up and rearward. Without full freedom
to move their legs to compensate, the astronauts found the best was to
move was to "hop." A better suit design would probabibly eliminate most
of the "Lunar gait."

                        Frank Crary

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

Date: 2 Jun 91 21:08:37 GMT
From: newton.cs.jhu.edu![e-mail]  (Paul Callahan)
Subject: Re: Self-sustaining infrastructures

In article <[e-mail]> [e-mail] (Matthew DeLuca) writes:
>Looking at it in another way, you are counting on what would be the greatest
>revolution (artificial intelligence) since ENIAC was first plugged in to
>give us a routine operational capability in space.  Considering that AI
>belongs right next to nuclear fusion (we've almost got it, just another few
>years) in the 'future revolution' bin, you'll pardon me if I remain
>skeptical about the whole thing.

Actually, I would say that a versatile autonomous robot (self-repairing, etc.)
is a good deal *less* ambitious than most AI goals, at least from the
standpoint of the intelligence it would have to have.  For example,
even a single-celled animal like an amoeba is an extremely versatile machine.
Robots with only as much behavioral complexity as amoebae would probably be
sufficient for the maintenance of a space station, yet few would say that
their behavior was very intelligent.  In contrast, AI researchers are
continually trying to simulate degrees of cognition that are found only
in humans.

I don't wish to imply that designing maintenance robots will be easy; I just
don't consider AI to be the bottleneck.  My bet is that we will have autonomous
robots before we attempt large-scale industrial exploitation of space
resources.  I would, of course, like to see both within my lifetime.

--
Paul Callahan
[e-mail]

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

End of SPACE Digest V13 #682
*******************