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Subject: SPACE Digest V12 #109

SPACE Digest                                     Volume 12 : Issue 109

Today's Topics:
       Re: Free Space Station - spacious but needs work
        Re: Negative Matter [was Anti-Gravity Devices]
            Re: HST, Perkin-Elmer and NASA
              Re: Why drop the shuttle?
 Re: Earth moving (was Re: Is an asteroid capture possible/feasible?
              Re: Nasa's budget
            Re: "Captain Midnight"
              Re: buying Soyuzes

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

Date: 14 Jul 90 12:44:00 GMT
From: mailrus!news-server.csri.toronto.edu!torsqnt!tmsoft!masnet!f906.n250.z1.fidonet.org![e-mail]  (maury markowitz)
Subject: Re: Free Space Station - spacious but needs work


  The idea of using the ET is neither new (as you mentioned) or all that
possible at this point.  As good as the ET is for space construction, like
similar construction here on the ground, laybor is the BIG cost.  Sure the
thing is up there, and sure it was designed to be refitted, but in most
cases it's STILL less expensive to build something down here and ship it
up.  NASA has done a LOT of research into the subject, and they just don't
think it's feasable at this point.  Then again, that's if you use NASA's
definition of a space station.
  There was one proposal by Global Outposts to build a simple,
unpresurized station called the "Outpost".  The idea was that the system
would have little more than power, but in a lot of cases, that's all you
need.  Since the astronauts would be protected from both sunlight and
meteors, and air could be piped, space suits for use in the Outpost COULD
be significantly simpler and lighter that the normal Shuttle suits.  It's
an interesting idea, it's cheap and certainly has SOME uses, but it's
certainly not what NASA calls a space station!
  It's also not THAT hard to pressurize the tank, but now you run into
problems of doing a lot of work on the interior, and that's expensive.  If
you consider that the only difference between this type of proposal and
NASA's space station is size, the actual use seems limited, a complete re-
fit in orbit would be amazingly expensize.
  Personally, I've put a lot of thought into ways of decreasing the time
required to do "interior design", and finally came up with something I
call "Space Lego".  With these small (light) building blocks and a lot of
cable (for tension) you can build some VERY strong interior bulkheads and
walls.  Set up time was the main consern, and I think these could be put
together fairly fast.  Unfortuantely, this still probibly isn't fast
enough, and things in free fall usually take a LOT longer than you
predict!
  Anyway, for those that are interested, I'm sure NASA would be very
interested in any idea you may have that may be useful, here's what you
have to work with...

  One large tank, 47m long, 8.4m diameter.
The larger of the two tanks, the hydrogen tank, is fitted with a "manhole"
at the aft end for the fitting of a bolt in airlock.  If you can get this
off, you can stuff everything you need in first, then put in the airlock
later.
Dry weight, 76000 lbs.  Sounds like a lot, but it actually isn't.
Remember that the Shuttle leaves the thing right on the edge of orbit, in
fact, at 98% or orbital speed.  As far as the Shuttle is conserned, taking
the thing ALL the way requires only the equivalent of 1750lbs.  Since the
Shuttle rairly flies full, tanks could easily be taken into orbit on ANY
launch in the near future.  The tanks still have residual fuel in them,
and the sun will cause the tanks to presurize, so the fuel has to be bled
off.  NASA was studying the ability to bleed off the gas though the
engines after MECO, but I don't know the results of the study.
  Problems... well, for one, it's BIG.  It's three times the size of
SkyLab, and it would be hard to fill the whole thing.  If what you want is
a small lab, it's a pretty good deal (I've done some back of the envelope
designs myself in my off hours) and leaves a LOT of room for experiments.
In fact, the Oxygen tank itself is more than large enough for a fair sized
station, but presents problems of it's own.  For another, you should carry
everything you need to get it running in ONE shot.  Once the airlock is in,
 you'll have considerable less room, and the trouble of cycling the locks
to get in new material.  This could present a problem, or you could just
live with it unpressurized for a few missions until it's done.  Another
problem is that the tidal forces will definitely point it "down".  Either
you live with it (and restrict your microgravity area), or you deploy some
very long rods to allow their tides to stablize the tank in it's "flat"
flying direction.  The AstroMast would be great for this.

                                                         Maury

--- Maximus-CBCS v1.00
 * Origin: The Frisch Tank, Newmarket, Ontario, CANADA (1:250/906)

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

Date: 23 Jul 90 02:16:06 GMT
From: usc!cs.utexas.edu!news-server.csri.toronto.edu!helios.physics.utoronto.ca!physics.utoronto.ca![e-mail]  (Christopher Neufeld)
Subject: Re: Negative Matter [was Anti-Gravity Devices]

In article <[e-mail]> [e-mail] (Brian or James) writes:
>    How would one remotely observe 'negative matter' if such a beast
>existed? I assume that photons would be 'negated' by hitting NM rather
>than reflected. NM strikes me as very much a black cat in a coal room at
>midnight situation.
>
   No, that would run into problems with energy conservation. Normal
matter in the form of isolated atoms interacts with photons through QED
processes. The simplest such process is: photon+atom -> excited atom ->
photon+atom. The photon is scattered in another direction. Anyway, the
interaction of a photon with an atom is purely electromagnetic. If we
posit "negative matter" whose response to a gravitational field is to
move in the "wrong" direction, but is otherwise composed of charged
particles in bound states, then it should behave qualitatively the same
as normal matter in interactions with photons.
   BTW, somebody mentioned that antimatter does not go the "wrong" way
in a gravitational field. This is a theoretical prediction which has not
yet been tested. Check the latest (July 1990) issue of _Physics Today_.
There is an article confirming the equivalence to about 10^-8 in
inertial mass for antimatter and matter, but the article explicitly
states that the test for gravitational mass has not yet been performed.

>                                 JDN
>


--
 Christopher Neufeld....Just a graduate student  | "The eagle may soar, but
 [e-mail]    Ad astra! | the weasel never gets
 cneufeld@{pro-generic,pnet91}.cts.com           | sucked up into a jet
 "Don't edit reality for the sake of simplicity" | engine."  Simon & Simon

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

Date: 22 Jul 90 16:43:53 GMT
From: drivax![e-mail]  (Kral)
Subject: Re: HST, Perkin-Elmer and NASA

In article <[e-mail]> [e-mail] (Doug McDonald) writes:
>There is sufficient info already: A bad figure is ground and polished into
>a mirror. The actuators they have for figure correction aren't strong
>enough to correct it. They didn't test the whole scope before launching.
>
>That is enough data right there. No more is needed.
>Isn't that enough?

No.  What I saw in the hearings was a mind set within NASA that said "Big,
expensive complete systems tests are not necessary because it is possible to do
enough componenet testing to prove the system."  What they seemed to be
overlooking, and I think this is what Al Gore was pursuing, was that they
didn't have a way of determining how thorough there component testing was until
they discovered that something failed.

The NASA admins would say "I'm sure we'll look back and find a test that could
have uncovred this problem without necessitating a complete systems test".  But
the problem is they can't seem to determine the need or the configuration of
the test until there has already been a failure.

The point being, that this kind of mind set will continue to cause massive
headaches until it is corrected, and we wouldn't know to correct it without
pursuing the interrogation, er, investigation with NASA officials.   Chopping
heads could have left the problem in tact.

--
kral * 408/647-6112 * {uunet|amdahl}!drivax!braun * [e-mail]
The most exciting phrase to hear in science, the one that heralds new
discoveries, is not "Eureka!" (I found it!) but "That's funny ..."
  -- Isaac Asimov              [Friends don't let friends use DOS]

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

Date: 20 Jul 90 13:35:50 GMT
From: sdd.hp.com!elroy.jpl.nasa.gov!peregrine!ccicpg!cci632!rit!moscom![e-mail]  (Jim Watson)
Subject: Re: Why drop the shuttle?

In article <[e-mail]> brycen@.UUCP (Bryce Nordgren) writes:
>>Not very practical: The shuttle weights 90 tons, more than 4 Mirs, and
>
>Egads!  I had no idea.  I knew it was heavy, but didn't know quite how much.
>

   Actually the empty shuttle only weighs about 56 tons.  I happened to
remember this little tid-bit since that's just less than an M-60 tank
which is significantly smaller and slower.

Jim

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

Date: 17 Jul 90 17:33:33 GMT
From: usc!zaphod.mps.ohio-state.edu!math.lsa.umich.edu!rphroy!cfctech!teemc!fmeed1![e-mail]  (Russ Cage)
Subject: Re: Earth moving (was Re: Is an asteroid capture possible/feasible?

In article <[e-mail]> [e-mail] (Gordon J. Mohr) writes:
>In article <[e-mail]> [e-mail] (Dieter Kreuer) writes:
>>
>>There has been a fairly long discussion about nuking earthbound asteroids
>>in sci.astro recently. While I totally agree to try everything to move
>>such a dinosaur-killer in any other direction than towards Earth, I would
>>strongly refuse to bring such a thing intentionally close to our planet.

Mr. Kreuer is unduly fearful.  Doing a gravity-whip maneuver past
the Earth could put such an object on an escape trajectory, where
it would never be a threat to us again.  This does mean flying
close by, but when we can hit a 1-mile wide window a billion miles
away at Saturn, we can do much better than that in our back yard.

>Actually, I understand that Russian scientists have calculated that, given
>enough warning, it would actually be easier to MOVE THE EARTH than divert
>a distant, rapidly approaching asteroid. How? Altering the moon's mass with
>nuclear charges. The moon's orbit would change, also affecting the Earth's
>solar orbit. A slight change, over time, would mean a gigantic difference
>in where the Earth is at some future time.

It's hard to take this seriously.  Think about it for a moment.  If
you have a tiny object (say, 10 km diameter), and you know its path
accurately enough to know that changing the earth's speed by 1 mm/sec
will avoid a collision X years in the future (X > 10, since 1 mm/sec
over 10 years is only 315 km), then changing the velocity of the
object by the same amount will also avoid the collision.

The ratio in masses between a 10 km object and a 12,800 km object
of the same density is 2,097,152,000 (2.1e9).  The ratio of energy
needed to make the same delta-V is also 2.1e9.

Let's get real, shall we?
--
Russ Cage    Ford Powertrain Engineering Development Department
Work:  itivax.iti.org!cfctech!fmeed1!cage   Home:  [e-mail]

I speak for the companies I own, not for the ones I don't.

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

Date: 22 Jul 90 17:02:29 GMT
From: ox.com!itivax!vax3.iti.org![e-mail]  (Allen W. Sherzer)
Subject: Re: Nasa's budget

Michael V. Kent writes:

>In response to Allen Sherzer, who does not like the Spacelab program because
>it flies "only 3 days a year."

On the contrary: I think Spacelab is great. In fact, I think it is so
great that we should utilize it as much as possible so we can do more
science for less money. We cannot do this with the Shuttle.

>Allen, may I ask politely, have you looked at a manifest lately?  Over the
>next 5 years, about one third to one half of the Shuttle flights will be
>Spacelab flights, most of which will last 10 to 13 days.  With a few planned
>modifications, several of these will extend to 16 to 28 days.  In fact, 3 of
>the next 6 flights are Spacelab flights of about 10 days each.

Actually, I had not looked at the maifest. Thanks for your correction. Now,
let's look at the numbers. You say 30 to 50% of flights will be spacelab
which means 3 to 5 flights a year. Let's assume an average of four flights
for each of the next five years. Let's also assume each flight lasts two
weeks. At $300M per flight that gives us over the next five years:

Number of flights:         20
Number of days in orbit:   280
Cost (20 shuttle flights): $6 billion

Now, let's assume we have a space station like LLNL's Earth Station and
use expendables. We will charge half the development and launch costs
of the station to Spacelab. We also assume two full heavy lift launches
are needed every year for support (although I suspect one would be enough).
Finally, one shuttle launch is budgeted to put Spacelab in orbit (although
it might be cheaper to send it on an expendable). To even it out, we will
also add in $875M for misc expenses.

Station development & launch
(Spacelab 50% share):         $325M
Shuttle launch:               $300M
5 years expendable launches:  $1.5B
Misc. expenses:               $875M
                              ------
Total cost                    $3B
Total days in orbit:          1825

So with expendables we get over 7 times the utilization of spacelab for
half the costs over five years. Note that this includes a big chunk of
station development costs.

So thanks for your correction but it is not relevant to the issue. The
more you utilize Spacelab with the Shuttle, the worse it becomes. It will
cost you over $42 billion to get the amount of utilization I can get with
$3 billion. We could buy a lot of spacelabs with the $39 billion we would
save.

>While using a Shuttle to play space station is not ideal, it is good enough for
>the next five years.  By then, Freedom will (hopefully) be coming online and
>will be able to take much of the burden off of the Shuttle.

Freedom will not be on line in 5 years. Not even NASA says that and current
(not released) figures indicate that it won't be on line this century. I also
point out that NASA has no plans to put Spacelab in orbit with Freedom.

As to it being good enough for the next five years, I submit that it is
not good enough. In three years we could have the vehicles and station on
line. We could reduce launch costs to 20% of what the Shuttle costs now.
The way it is right now, our critics (correctly) say that space is too
expensive. If we don't abandon our old high cost methods and embrase new
low cost ways, we just play into the hands of those who would shut it all
down. We are just making it easier for them to kill more programs.

What we are doing now is *NOT* good enough and must change.

>Granted, Shuttle
>and Freedom seem to be having some problems right now, but do you honestly
>believe Heavy Lift Delta and your capsule won't either?

I suspect it will. I also suspect McDonnell Douglas has taken that into
account. Remember, they are betting half a billion of their own money
(not ours) that they can do it. That gives me a great deal of confidence
and tells us we have nothing to loose.

>While it is good to hear some new ideas on what could be done, let's not lose
>sight of what we are doing.

Agreed. I'm trying to reduce the cost to orbit so we can do more in space.
By advocating low cost alternatives I am not loosing sight of that goal.

What is your goal?

  Allen
|                          |      In War: Resolution                      |
| Allen W. Sherzer         |      In Defeat: Defiance                     |
|   [e-mail]            |      In Victory: Magnanimity                 |
|                          |      In Peace: Good Will                     |

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

Date: 22 Jul 90 13:22:30 GMT
From: portal!cup.portal.com![e-mail]
Subject: Re: "Captain Midnight"

If memory serves correctly, I believe Captain Midnight was from
Ocala, Florida, although I don't remember his real name.  He was caught
and was sentenced to 6 months in jail and his gear was confiscated.  Like
you said, it was a long time ago and I could be way off on the details.

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

Date: 16 Jul 90 18:01:00 GMT
From: usc!cs.utexas.edu!news-server.csri.toronto.edu!torsqnt!tmsoft!masnet!f906.n250.z1.fidonet.org![e-mail]  (maury markowitz)
Subject: Re: buying Soyuzes


 p> a smaller Apollo would be about the size of the Soyuz.

  No it wouldn't.  Even the full-sized model of Apollo had considerably
less internal room than the normal Soyuz.  Take a look at pictures of them,
 the Soyuz has two "rooms", either of which has the same or more workspace
than the Apollo.
  This makes sence though, the Apollo carries a LOT of dead weight around
with it, the re-start moon return engin and fuel, enough H2/O2 to keep the
fuel cells going (Soyuz uses solar cells) plus the normal manuvering
rockets that Soyuz carries.  Apollo was BIG, but most of it was support,
not workspace.
  Soyuz on the other hand, was built to be used in LEO right from the
start (a special edition would be used for the moon shot).  It has little
support (nor does it need it) and carries little fuel, just enough for
manuvering and re-entry burn.  The Soyuz is considerably better for LEO
work than Apollo.  A new design for an American LEO "shuttle" capsule
would probibly be built from scratch, and be better than either, after all,
 both Apollo and Soyuz are 25 years old (at least) and we've learned a LOT
since then.
  By the way, does anyone know why they change the docking adapter design?
 The original one used on Apollo/Soyuz was built to be retrofitted onto
existing Soyuz capsules (but I don't think they use it) and all future
American designs.  The original had a 3-bladed adapter, but looking though
"Space Stations and Platforms" (a little dated), the neew design has 4
blades and is considerably smaller.  What happened?  Are the Soviets
changing the design too?

                                                            Maury

--- Maximus-CBCS v1.00
 * Origin: The Frisch Tank, Newmarket, Ontario, CANADA (1:250/906)

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

End of SPACE Digest V12 #109
*******************