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Subject: SPACE Digest V11 #154

SPACE Digest                                     Volume 11 : Issue 154

Today's Topics:
             Re: Power Economics and SPS
           Commercial Titan/Intelsat Launch Failure
      Re: Fun Space Fact #1: Launcher Development Costs
          Re: Observations of STS 36 and its Payload
                Power
        Re: Resolving Power of Hubble Space Telescope
              Ulysses at Jupiter
Shuttle Designs (was: Re: Fun Space Fact #1: Launcher Development Costs)
               Giotto Update - 03/14/90
       Re: NASA Headline News for 03/07/90 and 03/08/90
                HST resolution
----------------------------------------------------------------------

Date: 15 Mar 90 15:04:52 GMT
From: zaphod.mps.ohio-state.edu!sunybcs!uhura.cc.rochester.edu!rochester![e-mail]  (Paul Dietz)
Subject: Re: Power Economics and SPS

In article <[e-mail]> [e-mail] (Russ Cage) writes:
>[Followups directed to sci.space.]
>
>All ideas go through 3 stages of acceptance:
>
>1.)    It won't work.
>2.)    It'll work, but why would anyone want to?
>3.)    I always thought it was a good idea.
>
>I think Paul Dietz is between stages 1 and 2 WRT SPS.

No, actually between 2 and 3: "it will work, eventually, but
it will be very expensive to get there; still I think it will
happen, someday."

>In article <[e-mail]>, Paul Dietz writes:
>>Russ, you ignore: (1) the cost of keeping people in space (it's
>>currently very high), (2) the fact that no one has built a space
>>station beyond LEO, where it would require consider shielding.
>
>Look at the LLNL proposal for a program of a space station, moon
>base, and Mars base.  Total cost for all 3:  about $10 billion.
>Even if they are off by a factor of 2, that's still cheap.  That
>will establish the technology in no uncertain terms.

But the LLNL assumes significant risk, a risk too high to tolerate
in an industrial (as opposed to exploration) setting.

>Shielding material is available for free on the moon.  It's called
>regolith.  The LLNL and NASA proposals both call for using it.  A space
>habitat won't have any raison d'etre until it has something to process
>(more regolith).  The original space habitat shield can be raw regolith,
>which can be replaced with processing by-products later.

But getting this regolith off the moon is nontrivial.

>>Sorry, [cheaper transport is] essential.  A lot of material would still
>>have to be sent into space, even with largely ET resources.
>
>Numbers?  I haven't any handy, my studies were all borrowed or are on loan.
>(Remember, commercial Proton is available for $750/lb now...)

Well, you listed the industries required (at least 9).  I suspect they
add up to thousands of tons, at least.  Remember that not all parts
will work the first time; some parts of the system will probably have
to be redesigned and reinstalled, perhaps several times.

>Technologies like extrusion, vapor deposition, sintering, assembly,
>and draglines are very mature.

Not in space.  For example, machinery on earth assumes the existence
of an atmosphere, which affects heat dissipation.

>>We *don't* have the technology until someone spends the money
>>to develop it.
>
>Good point, BUT:  the level of existing technology and basic suitability
>for the intended purpose gives good cause to believe that the required
>amount of money will be small rather than large.

Again, I come to the opposite conclusion.  I think on the
order of 10^11 dollars is a fair rough estimate of the costs.

>Of course, you could take the position that as long as it isn't
>working yet, the potential costs are still too large to make it
>practical.  This is how I read you, and that's too pessimistic.

I didn't say $100 B's was too much to be practical.  This thread began
with a *comparison* of the cost of ground based vs. space based solar;
the argument is the latter would require much more investment to
prove.  Whether the investment would be worthwhile, I didn't adress.

>> [mass driver] drive coils, doesn't include superconducting bucket coils,
>>doesn't
>
>Superconductors aren't necessary.  Convenient, but not required.
>There are literally dozens of ways to make this thing work.  I
>thought of 2 more ways of powering bucket coils in a few hours.

Yes; I suspect a real system would use solid aluminum or beryllium
buckets, powered by induction.

>>prove that the launcher can achieve the necessary velocity accuracy,
>
>Quibble.  What did they spend on MD I-III?  $50K?  What do you think they
>could prove with, say, $10M?  That is mighty cheap.

Not a quibble -- *you* were holding up MD-III as proof that
the technology is available.  I agree MD III is cheap.  It is also
inadequate to prove a mass driver would work in practice.

>It should be possible to test things at full scale on the ground
>in actual-size pressure vessels.

That doesn't simulate lunar gravity.

>>Why should laser beams have this high a power density?  [10 KW/m^2]
>
>Because it's easy to do, and with hundreds of thousands of the
>things instead of a few hundred they'd be impossible to police?

Careful, Russ.  That's a great argument for outlawing space
development altogether, since anyone with a few kilotons of
mass in space could drop it on any city, and with megatons
out there, they'd be impossible to police. :-)

    Paul F. Dietz
    [e-mail]

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

Date: 16 Mar 90 03:33:49 GMT
From: agate!headcrash.Berkeley.EDU![e-mail]  (George William Herbert)
Subject: Commercial Titan/Intelsat Launch Failure

Yesterdays attempted launch of a commercial Titan III with an Intelsat VI
comsat aboard apparently failed.  From sketchy reports, it looks like the
transfer stage did not seperate from the second stage, and the Intelsat VI
was stranded in LEO after being jettisoned from the second/kick stages after
the seperation failure.
    Reports [unconfirmed] stated that there was a loss of signal with the
    sattelite.
Additional reports from NORAD's space tracking people suggested that the
Intelsat was in a orbit that was stable for at least twelve days, and could be
stabilized further with the use of the onboard thrusters.

If anyone has better info that this please post it asap, as a large number of
people are interested...  thanks

-George William Herbert

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

Date: Wed, 14 Mar 90 12:35:42 CST
From: [e-mail]
Subject: Re: Fun Space Fact #1: Launcher Development Costs

> concertina![e-mail]  (Steve Hix)

> Assuming 300 passengers in the B-747, its maintainance requirements
> in man-hours/passenger-mile probably isn't any more than the 150 Cessna
> 152's that would be needed to carry the same number of people.  Likely
> quite a bit less.

Pardon me, but so what?  The only thing that you've shown is that
it's possible to play jiggery-pokery by choosing measures.  In any
case, you seem to have rather lost sight of where this discussion
got started.

Let me show you what's wrong with your statement.  If we measure the
maintenance requirements for the Shuttle in man-hours/pound-mile,
*it* probably isn't any more than the Boeing 747 either, especially
if we assume it goes up carrying its full rated cargo weight, keeps
it through an extended mission, and then leaves it up there when it
comes down.  And it looks even better if you compare it to some other
high-speed vehicle, like the Concorde or an SR-71.

Now, given that there never has been any disagreement (I don't
think) that the maintenance requirements of the Shuttle system are
much too high, it's pretty obvious that the kind of comparison by
choice of units you (and I) made doesn't mean a whole lot.

Fact 1:  The Shuttle is significantly bigger and has much more
delta-v capacity than the original design.

Fact 2:  This redesign made the Shuttle much more complex.

Fact 3:  This increase in complexity increased the maintenance
requirements drastically.

Now, which of those are you trying to refute?  That *was* where all
this started.

==============================================================================
| Fred McCall  ([e-mail]) | My boss doesn't agree with anything  |
| Military Computer Systems           | I say, so I don't think the company  |
| Defense Systems & Electronics Group | does, either.  That must mean I'm    |
| Texas Instruments, Inc.             | stuck with any opinions stated here. |
==============================================================================

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

Date: 15 Mar 90 22:03:38 GMT
From: heurikon![e-mail]  (Ray Lampman)
Subject: Re: Observations of STS 36 and its Payload

In article <[e-mail]> you write:
>
>                    Observations of STS 36 and its Payload
>                    --------------------------------------

This is one of the BEST Usenet articles I've seen in recent months. I enjoyed
reading the observations of your observers. Please continue to track and post
summaries of future missions. I look forward to these observation summaries
becoming a regular feature on Usenet. And thank you to you and your observers.

Ray Lampman
--
I say what it occurs to me to say, when I  | Ray Lampman, (usa)608-276-3431
think I hear people say things, more I can | uunet!uwvax!heurikon!lampman
not say.  Oh, my cat, I call him `Moose'.  | 3201 Latham, Madison, WI 53713

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

Date:         Thu, 15 Mar 90 14:42:48 PLT
From: Wayne Fellows <[e-mail]>
Subject:      Power

Has anyone considered using a solar heated boiler system for powering a space s
tation/vessel?  Would the cost be lower to design, build, and put into orbit th
an a nuclear or SV system?  The technology certainly exists (how much r&d could
 one need to make a big tin can with a mirror on it?)

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

Date: 14 Mar 90 17:30:41 GMT
From: bfmny0![e-mail]  (Tom Neff)
Subject: Re: Resolving Power of Hubble Space Telescope

One quick question, if speckle interferometry is 'solid' now: was
that early Betelguese disk image bogus or not?  Are stellar disks
being resolved now?
--
Perestroika: could   \O\     Tom Neff
 it happen here?      \O\    uunet.uu.net!bfmny0!tneff

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

Date: 12 Mar 90 18:05:03 GMT
From: cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!uakari.primate.wisc.edu!nic.MR.NET!jhereg!orbit!pnet51![e-mail]  (S Schaper)
Subject: Ulysses at Jupiter


  I would like to add my vote for (since it has undoubtedly been already
proposed), that Ulysses would run its' instrumentation as it flys by Jupiter.
This would give us some intermediate data on changes there, such as the
missing cloud belt, the changes in the Red Spot, and vulcanism on Io, if it
has a camera, that is, to compare with Gallileo when it gets there. This would
also give the ESA its' first outer planet mission. And comparative results on
the instruments' actual settings to compare with the Solar flybys.

UUCP: {amdahl!bungia, uunet!rosevax, chinet, killer}!orbit!pnet51!schaper
ARPA: crash!orbit!pnet51![e-mail]
INET: [e-mail]

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

Date: 16 Mar 90 04:04:58 GMT
From: agate![e-mail]  (William Baxter)
Subject: Shuttle Designs (was: Re: Fun Space Fact #1: Launcher Development Costs)

In article <[e-mail]>, mccall@skvax1 writes:
>Fact 1:  The Shuttle is significantly bigger and has much more
>delta-v capacity than the original design.

The original 'design' was not well defined.  It was, for the most part,
a set of promises about performance. (e.g. $100/lb to LEO, fully reusable)

>Fact 2:  This redesign made the Shuttle much more complex.

You are comparing existing hardware with a bunch of promises.

>Fact 3:  This increase in complexity increased the maintenance
>requirements drastically.

Comparing apples and hypothetical oranges is irrelevant.  What's the
total launch cost of the 'original design,' and what is the unit cost
per kilo?  How much will it cost to build?  How does the maintenance
schedule differ from that of the existing Shuttle?

In a commercial industry, failure to obtain good cost estimates as part
of a design before entering production can bankrupt the company.  Only
the deep pockets of government keep the NASA shuttle operations from the
same fate.

New promises to Congress are commonly known as Space Station Freedom,
National AeroSpace Plane, Advanced Launch System, and the Moon-Mars Thing.

>==============================================================================
>| Fred McCall  ([e-mail]) | My boss doesn't agree with anything  |
>| Military Computer Systems           | I say, and I take all of his          |
>| Defense Systems & Electronics Group | comments as personal attacks, too.   |
>| Texas Instruments, Inc.             |                       |
>==============================================================================

William Baxter

ARPA: web@{garnet,brahms,math}.Berkeley.EDU
UUCP: {sun,dual,decwrl,decvax,hplabs,...}!ucbvax!garnet!web

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

Date: 14 Mar 90 17:39:49 GMT
From: cs.utexas.edu!usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Giotto Update - 03/14/90


                       Giotto Extended Mission Update
                             March 14, 1990

     Yesterday, the Giotto spacecraft successfully performed its first
orbit correction manuever to place itself on a optimal path for a
Earth flyby on July 2. Giotto is currently going through a checkout
of its science instruments which is expected to last one month. If the
spacecraft or its scientific payload health are not satisfactory, then
the Giotto Extended Mission (GEM) will be terminated around the end
of May. Otherwise, Giotto will be retargeted for encounter with comet
Grigg-Skjellerup using an Earth flyby this coming July. After the Earth
flyby, Giotto will be put into hibernation and then reactivated in late
1991 or early 1992. Giotto will then encounter Grigg-Skjellerup in July 1992.

     Giotto is owned by the European Space Agency (ESA) and controlled
in flight by the European Space Operations Center (ESOC) in Darmstadt,
Germany. Contact is established and maintained using the Jet Propulsion
Lab's 70 meter antennas in Spain, California and Australia. During the
checkout of the scientific payload, the telemetry rate will be 46K bps
at X-band using the spacecraft's high gain antenna. Activities after
the paylaoad checkout phase will include a radiometric campaign to
perform ranging measurements.


 Ron Baalke                       |    [e-mail]
 Jet Propulsion Lab  M/S 301-355  |    [e-mail]
 4800 Oak Grove Dr.               |
 Pasadena, CA 91109               |

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

Date: 13 Mar 90 21:37:29 GMT
From: convex![e-mail]  (Dave Dodson)
Subject: Re: NASA Headline News for 03/07/90 and 03/08/90

In article <[e-mail]> [e-mail] (Lou Adornato) writes:
>>Workers are closing off a high pressure leak, residual liquid
>>oxygen and liquid hydrogen reactants are being offloaded and...
>
>I'm surprised that these aren't vented out between the deorbit burn and
>re-entry.  I'd certainly feel a lot better knowing that there wheren't several
>(hundred?) Kg of either of these on board during re-entry and landing,
>especially if they weren't needed.

I think you'd rather have the electricity produced by these reactants
in the fuel cells, wouldn't you?

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

Dave Dodson                                     [e-mail]
Convex Computer Corporation      Richardson, Texas      [phone]

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

Date: Thu, 15 Mar 90 14:57:14 EST
From: John Roberts <[e-mail]>
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
Subject: HST resolution


Overall resolution is affected by both the optics and the image sensor.
I believe the optics are nominally rated at 20 milliarcseconds (at some
particular wavelength). The CCD pixel density, however, limits single
photographs to 100 mas resolution. If the object being photographed is
steady (true for most celestial objects), then you can get around the
pixel resolution limitations by taking several photos with the telescope
pointed in very slightly different directions, then computationally combining
the photos. Thus it should be possible to get nearly diffraction-limited
photos in most cases.

I have several technical articles on HST. I'll try to post a summary soon.

  John Roberts                HOMER'S BOSS: "And this must be - er - Brat."
  [e-mail]           BART: "Bart!"
                                     HOMER: "Don't interrupt the man, Brat."

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

End of SPACE Digest V11 #154
*******************