Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_9/V16NO939.TXT

Text File | 1993-08-03 | 29KB | 696 lines

Space Digest                Thu, 29 Jul 93       Volume 16 : Issue 939

Today's Topics:
                         11 planets (2 msgs)
                            Budget figures
                           Cats in zero gee
     Cold Fusion and its possible uses (if it is proven to exist)
            DC-X Prophets and associated problems (3 msgs)
Did our CCD catch a high orbiting satellite or a near-Earth asteroid?
                  GPS in space (was Re: DC-1 & BDB)
               Hubble solar arrays: how'd they foul up?
              Low Tech Alternatives, Info Post it here!
             NASA, Space Advertising! PR Work is needed.
Return of the sinister HST replacement thread! (was: DC-X Prophets..)
                space news from June 28 AW&ST (2 msgs)
                     Why I hate the space shuttle

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

Date: Wed, 28 Jul 1993 17:44:04 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: 11 planets
Newsgroups: sci.space

In <[e-mail]> [e-mail] (Henry Spencer) writes:

>In article <[e-mail]> [e-mail] writes:

>>Also seems I
>>remember there is a planet the other side of Pluto...

>A couple of little iceballs have been found out beyond Pluto, but nothing
>worthy of being called a planet.  There remains some speculation that
>there might be another planet out there, although various recent results
>have weakened that theory considerably.

Well, actually, there *is* currently a planet beyond Pluto, isn't
there?  I think it's called 'Neptune'.

[At least I think this is still the case -- I forget how long they
were supposed to be 'reversed' in distance due to orbital
eccentricity.]

[Does this count as having 'corrected' Henry?  When do I get my
membership card?  :-)]

--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

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

Date: 28 Jul 1993 16:13:48 -0500
From: Steven Reardon <[e-mail]>
Subject: 11 planets
Newsgroups: sci.space

In <[e-mail]> [e-mail] (fred j mccall 575-3539) writes:

>Well, actually, there *is* currently a planet beyond Pluto, isn't
>there?  I think it's called 'Neptune'.

Yep, until 1999.  Which, if I'm remembering right, is also about the time
Pluto's atmosphere will collapse.  Part of the reason behind sending two
cheap, short-development-time probes at Pluto before then is so we can have
a look at the atmosphere.

>[Does this count as having 'corrected' Henry?

Or is it just 'regarding' Henry?



--
I'm going to change my last name to Peece,
and name my first son Warren.

[e-mail] -- Steven Reardon Bradley U --  Peoria IL

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

Date: Wed, 28 Jul 1993 19:30:13 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Budget figures
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>In article <233j22$[e-mail]> [e-mail] (Michael C. Jensen) writes:
>
>>I found it interesting to note the slight discrepancys between the
>>posts claiming over $1 billion per shuttle flight, and the actual numbers,
>>which aim more towards a little under $500 million a flight.. still a lot
>>of money yes, but important to be close to accurate..
>
>There is no discrepancy. The half billion $$ per flight figure assumes
>that no development, construction, NASA overhead, or interest in included.
>In other words, it pretends the Shuttle was developed for free.

No, of course it doesn't. It assumes that bill is already marked paid,
which it is. Congress wanted Shuttle developed, they got it, they paid
for it. Whether Shuttle ever fiies again or not, that cost is sunk.

>The actual cost IS about a billion per flight but I am willing to live
>with the 'creative' accounting used to make it look better. Paying four
>times commercial rates for launch services is bad enouth. Although it
>is interesting to note that if NASA contractors accounted for things
>the way NASA does, they would be thrown in jail.

The government is the ultimate customer. It's not a business, it doesn't
work by business rules. It orders things, and pays for them with our
money. It doesn't make products. It doesn't sell products. It uses the
old sock method of accounting. It spends until the sock is empty, then
it puts a rock in there and goes out and mugs the taxpayer for some more
money.

Exactly which commercial launcher offers Shuttle capabilities at
1/4th the cost?

Gary
--
Gary Coffman KE4ZV          |    You make it,     | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems |    we break it.     | uunet!rsiatl!ke4zv!gary
534 Shannon Way             |    Guaranteed!      | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244     |                     |

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

Date: Wed, 28 Jul 1993 17:38:57 -0400
From: Kevin William Ryan <[e-mail]>
Subject: Cats in zero gee
Newsgroups: sci.space

[e-mail] (Keith Mancus)
>> Not a cat you like certainly.  And by the way, cats do not take well to
>> microgravity--it's been tried.
>
>  Could you give me a reference to this?  I wasn't aware it had ever been
>tried.

    I recall seeing a reference to this in Tom Wolfes 'The Right Stuff'.
Basically, nobody at the time thought the question worth a flight of the
Vomit Comet, so the sent a cat up in a fighter with a camera in the
cockpit. Most of the film shows the pilot trying to pull the cat off his
arm. When he finally did, the cat 'magically' levitated back to his suit
and remained there for the rest of the flight despite his best efforts.

    In other words, the only time _I_ know of it being tried the cat
wasn't too happy about it, and the pilot wasn't doing a very good job of
maintaining zero G due to the cat distracting him by attempting to claw
through him.

    I haven't personally heard of anyone doing it in that larger airplane.

                                                kwr

Internet: [e-mail]

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

Date: Wed, 28 Jul 1993 19:18:31 GMT
From: "Alex C. Anderson" <[e-mail]>
Subject: Cold Fusion and its possible uses (if it is proven to exist)
Newsgroups: sci.physics,sci.space

I just wanted to suggest a small correction to [e-mail]
>True, traditional QM measurements do say just that, but, listening
>to Pons at his Indiana University talk shortly after his press
>sonference and also reading the Conressional Committee's report, all

I was at the talk, which was held at IUPUI in Indianapolis, not IU which is
in Bloomington.  Perhaps a trivial point, but I graduated from there in
physics, and even though it is administered through IU-Bloomington, I like to
think we have our own identity.  As a matter of fact, it was the Chemistry
Department (run by Purdue) that had invited Pons... :)
--
-------------------------------------------------------------------------------
| Alex C. Anderson            |    [e-mail]          |
| P.O. Box 2204, W. Lafayette, IN 47906 |    voicemail:317-538-1157        |
-------------------------------------------------------------------------------

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

Date: 28 Jul 1993 14:24 CDT
From: [e-mail]
Subject: DC-X Prophets and associated problems
Newsgroups: sci.space

>There are no gurantees in life Doug. We need to make a choice between a
>pork laden space program which doesn't work very well, costs too much, and
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

My impression of public opinion of the space program is
just this.

>hangs by a thread or a cost effective space program that does more, costs
>less, and hopfully, will enjoy more public support.
>
>You might do well to look closer at the experience on DC. It went from
>being an unknown small effort to gaining wide acceptance in a very short
>time. In Congress, the House supports it and the Senate opposes it. The
>House has been briefed by insiders and activists (many of whom are on the
>net) and believes it to be a change from the buisness as usual you advocate.
>The Senate, on the other hand, hasn't been as extensively briefed and thinks
>SSRT is just another launcher project to fund the production of view
>graphs and opposes it for that reason.
>
>This shows that Congress will support a cost effective program but is
>loosing patience with the waste we have seen to date.
>


When I mention the DC series to people who are very negative on the space
program in general, I get a positive reaction almost every time.  Congress
isn't the only group of people sick of waste.  Even if the shuttle is
whiz bang great at what it does, it doesn't APPEAR to do anything to the
people who are footing the bill for it: Taxpayers.  The average person's
perception of a shuttle mission is a few fighter-pilot-rocket-jocks watching
insects mate in microgravity.  Space station Ed just seems to me to be a
continuation of this.  Whether or not this is really the case doesn't really
matter if that is what everyone thinks is the case.  About the best attitude
most people have toward space (other than the space Shiites) is apathy.
It is real easy to see a need to feed people (regardless of politics).  It is
hard to see a need to support apparently meaningless experiments on the
worlds most expensive launcher or the worlds most expensive space station.

Craig

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

Date: 28 Jul 1993 16:12:58 -0400
From: Pat <[e-mail]>
Subject: DC-X Prophets and associated problems
Newsgroups: sci.space

In article <[e-mail]> [e-mail] writes:
>isn't the only group of people sick of waste.  Even if the shuttle is
>whiz bang great at what it does, it doesn't APPEAR to do anything to the
>people who are footing the bill for it: Taxpayers.  The average person's


Actually,

    you should hear the comments on SHuttle from the
people in Space Science.  They comment on shuttle missions
costing 500 Million and taking 3 years  to manifest.

Plus they are terrified,  NASA will make an accounting change and
force the missions to carry more shuttle costs,  and then
they are screwed.

pat

A number of new science initiatives are based upon avoiding as much NASA
infrastructure as possible.   STS, DSN, TDRSS.  do it down and dirty
and simply.

--

God put me on this Earth to accomplish certain things.  Right now,
I am so far behind, I will never die.

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

Date: 28 Jul 93 13:48:27
From: Steinn Sigurdsson <[e-mail]>
Subject: DC-X Prophets and associated problems
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:


   In article <[e-mail]> [e-mail] writes:

   >>A valid one according to my research. We are now looking at TWO repair
   >>missions upping the total cost to well over $1B. If we assume that HST..

   >Hubble was designed to be repaired in orbit.  Now how much of those "repair"
   >missions are regular maintenance?  Certainly gyro replacement is.  Some of

   well, I suppose almost all of them are for maintenance. But since each one

You suppose wrong. WFPC-2 and NIC are scheduled instrument
replacements, to take place on separate flights. Of course
while you're up there you also do any other repairs you can.

 ...
   article in The Economist, the repair will cost $540 million plus Shuttle

 ...
   commercially procured HST would cost less than $300M (using Wales's figures).
   With a quanity buy, HST's can be had for even less, but we'll use the
   $300M figure. BTW, another article (The Economist, July 17, 1993) mentiones
   a BMDO project which could make a similar telescope for $300M which tends
   to confirm my number.

   So we take our $300M HST, and send it up on a Titan III (with a kick
   stage to boost to a higher orbit) or a Titan IV. Either vehicle can
   be had commercially for less than $200M.

   This gives us a total cost for a replacement HST at less than $500M
   which is half to a third of what NASA will spend to repair the old HST.

Are you also figuring on duplicating the TDRSS network?
Where is money for ground operations, scheduling and data
analysis coming from?

|  Steinn Sigurdsson    |I saw two shooting stars last night        |
|  Lick Observatory    |I wished on them but they were only satellites    |
| [e-mail] |Is it wrong to wish on space hardware?        |
| "standard disclaimer"    |I wish, I wish, I wish you'd care - B.B. 1983    |

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

Date: Wed, 28 Jul 1993 21:16:28 GMT
From: Claia O Bryja-2 <[e-mail]>
Subject: Did our CCD catch a high orbiting satellite or a near-Earth asteroid?
Newsgroups: sci.astro,sci.space

While observing (or, rather, trying to observe-- there were some clouds) with
a 30-inch telescope and a CCD just east of Minneapolis/St. Paul, our camera
snapped the motion trail of something interesting.  The exposure time was 15
seconds, and the trail extended about 100 arcsec.  Going at that rate, if it
were a satellite in a circular orbit, it would have a period of about 50 or
60 hours.  This seems a bit long.  How many satellites orbit that far out?
The direction of the streak was close to north-south, and we were pointing
fairly close to zenith, so this satellite would have to be in a polar orbit
also (our latitude is 45 N).  We were wondering to ourselves if it might be
a near-Earth asteroid instead-- passing us beyond the Moon's distance.
Can anyone comment on how likely this might be?  I would naively think that
the north-south orientation would be unusual for an asteroid.  If anyone
happens to be interested in the details (time, position, magnitude, etc.),
please e-mail.
                            -- Claia

                            [e-mail]

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

Date: 28 Jul 1993 14:38:23 -0400
From: Pat <[e-mail]>
Subject: GPS in space (was Re: DC-1 & BDB)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (fred j mccall 575-3539) writes:
>In <[e-mail]> [e-mail] (Doug Mohney) writes:
>
|>However, to give Fred a little flame :-), $400 million in resulting performance
|>improvements between the Al-Li tank and ASRM isn't a bad envestment no matter
|>what orbit we end up in.
|
|Perhaps, but let's justify it on the basis of need, not create a
|mission as justification.


What is the difference?  I think it is a useful engineering improvement,
but there are no currently slotted missions that need this.

Because it doesn't exist,  no missions are planned.  SOmething has to jump start
the process.

--

God put me on this Earth to accomplish certain things.  Right now,
I am so far behind, I will never die.

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

Date: 28 Jul 1993 14:46:24 -0400
From: Pat <[e-mail]>
Subject: Hubble solar arrays: how'd they foul up?
Newsgroups: sci.space

 I would say the HST solar array problems  only point out that NASA
and ESA need a solid Engineering test bed program.

Once a year,   just boot some bird up with all the gear one is interested
in using in future missions.  Put it into some screw ball high inclination
highly elliptical orbit so it passes throught the ugliest
radiation fields,  gets lots oflight night cycles,  and
maybe even exposed to  outer atmosphere.  i

if the stuff stays healthy for 6 months,  one has much
better faith in the articles.

pat
--

God put me on this Earth to accomplish certain things.  Right now,
I am so far behind, I will never die.

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

Date: Wed, 28 Jul 1993 19:21:23 GMT
From: "Allen W. Sherzer" <[e-mail]>
Subject: Low Tech Alternatives, Info Post it here!
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Gary Coffman) writes:

>Big dumb vehicles like Saturn were horrifingly expensive, $500 million
>per launch and you threw away the vehicle after one use.

Saturn at the costs you give lifted stuff at $2,000 per pound which is
a third to half what current launchers cost. Not bad for something so
old.

BTW, since Shuttle costs even more per launch and only delivers a fifth
as much, then is it also 'horrifingly expensive'? After all, if a vehicle
which delivers payload for $2,000 per pound is horifing, then another
vehicle which costs over five times as much must be a lot worse.

>it [Shuttle] still costs $500 million a flight, though flights can accomplish
>more due to the large crew volume and cargo bay available.

I'll stick my Saturn launched Skylab against your Shuttle any day. Skaylab
had far more volume than Shuttle and we could get far more utilization
out of it for a fraction of what we spend on Shuttle.

   Allen

--
+---------------------------------------------------------------------------+
| Lady Astor:   "Sir, if you were my husband I would poison your coffee!"   |
| W. Churchill: "Madam, if you were my wife, I would drink it."             |
+----------------------9 DAYS TO FIRST FLIGHT OF DCX------------------------+

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

Date: Wed, 28 Jul 1993 18:05:26 GMT
From: Gary Coffman <ke4zv!gary>
Subject: NASA, Space Advertising! PR Work is needed.
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Allen W. Sherzer) writes:
>In article <[e-mail]> [e-mail] (Gary Coffman) writes:
>
>>Sadly, because I too would like to see massive space colonization in
>>my lifetime, PR is not a viable approach. Space already has a massive
>>PR presence for free thanks to science fiction and Startrek and activist...
>
>That's only part of what a PR firm does. They also spend a lot of time
>and effort figuring out what people WANT. What a PR firm could and
>should do is find what people want from a civil space program. There
>are some strong indications from sources like the Annenberg Study which
>indicate NASA isn't providing what the public is willing to pay for.

That's not a PR firm's job, that's the job of market research. The
first thing a market research firm does is identify the paying
customers. Presidential directives have sharply limited NASA's
customer base to a couple dozen Congressmen who write authorizations
and sign the checks. What do those Congressmen want? Pork for
their districts, and NASA delivers. There's no other reason that
NASA centers are spread all over the country causing transport
and coordination problems.

The public wants Startrek, but Paramount can deliver that and NASA
can't. Most of the public just wants us to stop throwing away money
in space, but feel powerless to stop it. A few more astute members
of the public understand that no money is spent in space, it's spent
in selected Congressional districts paying high tech workers. Some
want in on the largess, others call it aerospace welfare. A very
few see the concrete benefits of weather sats and comsats, but see
no reason to spend money unproductively looking at dead moons
or burned out planets.

Science, the high frontier, that's the province of a few dreamers.
It garners few votes. Pork and sideshows, bread and circuses, that's
what NASA is about, because NASA *has* done it's market research.

Gary
--
Gary Coffman KE4ZV          |    You make it,     | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems |    we break it.     | uunet!rsiatl!ke4zv!gary
534 Shannon Way             |    Guaranteed!      | emory!kd4nc!ke4zv!gary
Lawrenceville, GA 30244     |                     |

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

Date: Wed, 28 Jul 1993 21:38:20 GMT
From: "Allen W. Sherzer" <[e-mail]>
Subject: Return of the sinister HST replacement thread! (was: DC-X Prophets..)
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Steinn Sigurdsson) writes:

>   well, I suppose almost all of them are for maintenance. But since each one

>You suppose wrong. WFPC-2 and NIC are scheduled instrument
>replacements, to take place on separate flights. Of course
>while you're up there you also do any other repairs you can.

I guess I consider that part of maintenance. If you want to break upgrades
out separately, fine. The point remains that each of these missions costs
more than it would to build and fly a new HST.

>   This gives us a total cost for a replacement HST at less than $500M
>   which is half to a third of what NASA will spend to repair the old HST.

>Are you also figuring on duplicating the TDRSS network?

I figure with two HST's in orbit we control one all the time with TDRSS
and use the other whenever conditions permit. However, I suspect we could
use part of the savings to build a second control facility if we want. If
that's too expensive, I guess we just need to live with the idea of a
brand new instrument and a savings of half a billion in the bargin.

>Where is money for ground operations, scheduling and data
>analysis coming from?

That has always been a separate line item.

  Allen
--
+---------------------------------------------------------------------------+
| Lady Astor:   "Sir, if you were my husband I would poison your coffee!"   |
| W. Churchill: "Madam, if you were my wife, I would drink it."             |
+----------------------9 DAYS TO FIRST FLIGHT OF DCX------------------------+

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

Date: Wed, 28 Jul 1993 18:11:30 GMT
From: Paul Dietz <[e-mail]>
Subject: space news from June 28 AW&ST
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Henry Spencer) writes:

 > hand.  The weight savings needed to accommodate the LEAPs would be
 > had by using all-composite structure (Clementine 1's structure is
 > partly metal) and using Aerojet's ALAS (Advanced Liquid Axial Stage)
 > for higher-performance propulsion.  ALAS burns hydrazine and chlorine
 > pentafluoride for an Isp of 350s, highest for any storable fuel mix.
                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Ah, I think we may have caught Henry here...

Henry didn't say what the pressure or expansion ratio of this engine
is.  Let's suppose it is 100 psia and an area ratio of 20.  Then,
these are the theoretical Isp (shifting) for various fuels with
chlorine pentafluoride under those conditions...

    Fuel(s)            Isp (vac), sec.
    ---------------------------------------
    N2H4            351
    LiH            352
    Be+N2H4            362
    BeH2            373
    BeH2+N2H4        376
    Li            377

The "350" figure Henry quotes may be an actual Isp for a real engine,
in which case the area ratio is no doubt larger to compensate for some
of the inefficiency in any real engine.

Perhaps Henry meant any fuel combination that is fully liquid at room
temperature (no slurries, hybrids or molten metals allowed)?

    Paul F. Dietz
    [e-mail]

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

Date: Wed, 28 Jul 1993 19:41:14 GMT
From: Henry Spencer <[e-mail]>
Subject: space news from June 28 AW&ST
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Paul Dietz) writes:
> > ... ALAS burns hydrazine and chlorine
> > pentafluoride for an Isp of 350s, highest for any storable fuel mix.
>                     ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
>
>Ah, I think we may have caught Henry here...

Nope, you may have caught AvLeak.  If it's in one of my summaries, and
it's not in [], then "I don't make the news, I just report it" (or in
this case "I don't write the articles, I just summarize them").

>Perhaps Henry meant any fuel combination that is fully liquid at room
>temperature (no slurries, hybrids or molten metals allowed)?

I would expect that's what the BMDO people meant.
--
Altruism is a fine motive, but if you   | Henry Spencer @ U of Toronto Zoology
want results, greed works much better.  |  [e-mail]  utzoo!henry

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

Date: 28 Jul 1993 16:23:14 -0400
From: Pat <[e-mail]>
Subject: Why I hate the space shuttle
Newsgroups: sci.space

Michael Jensen again shows his lack of Knowledge....


  For what it's worth,  The DC-3  was very high Risk for it's
time  and considered very experimental..

    a 2 Engine Plane for Oceanic Flight??????

    a Monocoque construction Passenger plane?  This may be fine
    for race planes,  but not for reliable passenger transports.

    What they did, was build the DC-1,  then the DC-2  to
    prove the flight concepts,  the reliability and
    basic markets,  before going to the DC-3

pat

    BTW,  nowadays, its much harder for a 2 engine bird to get
    trans-oceanic  certifications or ETOPS.
--

God put me on this Earth to accomplish certain things.  Right now,
I am so far behind, I will never die.

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


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From: Paul Dietz <[e-mail]>
Newsgroups: sci.space
Subject: Re: Low Tech Alternatives, Info Post it here!
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In article <[e-mail]> [e-mail] (Gary Coffman) writes:

 > Big dumb vehicles like Saturn were horrifingly expensive, $500 million
 > per launch and you threw away the vehicle after one use.
 >
 > In the 20 years since Shuttle's design was frozen, we've developed
 > new materials and new methods that can simplify a launcher by replacing
 > many baroque bits with a few new improved bits with better performance
 > and better reliability. For example, one of the main concerns about
 > the SSME is the reliability of the turbopumps. We now know how to make
 > much better turbopumps than we did in 1970, thanks in part to the
 > experience we gained with Shuttle. We know how to make one piece SRBs,
 > or even liquid fueled alteratives with fly back capability as was orignially
 > intended. We know how to make ligher stronger ETs. ETC.
...
 > Rather than retreat to even older lower tech solutions, we should
 > press forward to develop even better new high tech that simplifies
 > designs and increases reliability.

Gary, you are laboring under some misapprehensions here.

Saturn V was not "big and dumb".  It has some quite sophisticated, and
expensive, construction.  Consider the fuel tanks, for example.  Their
fabrication cost hundreds of dollars per pound (1993 dollars).  A
cost-optimized design would have been "dumber"; making the tanks out
of steel would reduce the cost by at least an order of magnitude.
Another example: the F-1 engines had a thrust/weight ratio of nearly
100.  Their turbopumps achieved a power density of some 36 kW/kg.
That (let alone the > 100 kW/kg in the SSME turbopumps) doesn't make a
lot of sense on a first stage.  Bulkier engines with larger, lower
power density, pumps, or even pressure-fed engines, would have been
considerably cheaper.

It should be clear that some optimum cost vs. performance point must
exist for launch vehicle hardware.  What evidence is there that we are
on the low-performance side of that point?  Analysts in the 60s
concluded that, in fact, we were on the high side, and should make
less sophisticated, less complex vehicles, whose poorer mass ratio was
more than offset by much lower per pound construction cost.  We make
cars out < $1/lb sheet steel, not $1,000/lb exotic composites.  It is
not clear why rockets should be any different.

    Paul F. Dietz
    [e-mail]

    "Absolute stupidity of the worst sort"
        -- Freeman Dyson commenting on the space shuttle

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

End of Space Digest Volume 16 : Issue 939
------------------------------