Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V08/V8_295.TXT

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Date: Mon, 25 Jul 88 19:06:31 PDT
From: Ted Anderson <[e-mail]>
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Subject: SPACE Digest V8 #295

SPACE Digest                                      Volume 8 : Issue 295

Today's Topics:
            Re: NASA news - Seasat
       Re: Soviet launch 1st Phobos mission & Spacewalk update
              Electromagnetic Launchers
              Mars Face (again)
     Re: advance space news from June 6 AW&ST -- Pegasus!
              NASA support for industry
             Re: Von Braun quote
               Naming the Space Station
         Re: postings from LARC (was none BITNET eh?)
               Re: Space Suits
----------------------------------------------------------------------

Date: 5 Jul 88 16:55:23 GMT
From: aplcen!aplcomm!stdc.jhuapl.edu![e-mail]  (Jim Meritt)
Subject: Re: NASA news - Seasat

In article <[e-mail]> [e-mail] writes:
}An arbitrary `mean sea level' can be defined in terms of an
}equipotential surface, that is, a surface chosen so that any two
}points on the surface have the same gravitational potential.  To a
}fairly good approximation, the surface so described is nearly
}spherical, flattened slightly at the poles and heavier in the southern
}hemisphere.  The surface so described is the `reference geoid.'


You can also get some interesting bottom contour data from the geoid
structure.


Disclaimer: Individuals have opinions, organizations have policy.
            Therefore, these opinions are mine and not any organizations!
Q.E.D.
[e-mail] 128.244.65.5  (James W. Meritt)

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

Date: 11 Jul 88 15:58:02 GMT
From: ubvax!unisv![e-mail]  (Mike Van Pelt)
Subject: Re: Soviet launch 1st Phobos mission & Spacewalk update

In article <[e-mail]> [e-mail] (Rich Thomson) writes:
>I thought the soviets were using the space station to make very high quality
>silicon wafers and chips.  Is this incorrect?

I don't know about silicon, but the third solar panel that was installed
on MIR contains some germanium arsenide solar cells made from GeAs
crystals that were grown on MIR.
--
"When you strip all the  technospeak away,  they're claiming that it can't be
 done because it  hasn't been done yet,  and therefore, we ought not even try
 doing it, because it can't be done.  That's Luddite Logic if I ever heard it."
-- Tom Clancy on SDI.               Mike Van Pelt    [e-mail]

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

Date: Mon, 11 Jul 88 13:35:09 EDT
From: [e-mail] (Paul F. Dietz)
To: [e-mail], [e-mail]
Subject: Electromagnetic Launchers

I was thinking some more about the perennial problem of cheaply lifting
mass into orbit; specifically, using electromagnetic launchers.  Under
the assumption that we can launch high ballistic coefficient vehicles
out of the atmosphere at around escape velocity, what orbits should the
vehicles be launched into?  How much change in velocity would onboard
rockets have to supply?

The purpose of the system would be to launch acceleration insensitive
materials into space.  This could be very useful in supporting
(for example) manned Mars exploration.  Rocket fuel, water and radiation
shielding make up a significant fraction of the Mars vehicle's mass.

The vehicles could not just be unguided projectiles, like bags of
lunar material launched using a mass driver, since vehicles are
placed onto elliptical orbits with perigee beneath the Earth's surface.
Onboard rockets must lift the perigee above the atmosphere and guide
the vehicle to a space station.

Where to put the space station?  LEO is one idea, but LEO is hard to get
to.  Simply firing the vehicle to an orbit with an apogee several hundred
km up doesn't work, since the delta-V needed to circularize the orbit would
be huge.  One might reduce the delta-V by depressing the trajectory, but
atmospheric heating kills you .  A more complicated procedure is called for:

   1. Launch vehicles into a highly eccentric orbit with apogee
      well beyond GEO.  The orbit must pass through the plane of
      the LEO space station's orbit at a point distant from the earth.
   2. When the vehicle intersects the station's orbital plane,
      use the engine to put the vehicle into that plane with perigee
      in the upper fringes of the atmosphere.
   3. Lower the apogee using aerobraking, perhaps over many orbits
      to avoid overheating.  This should reuse the heat shield
      used during the vehicle's initial ascent.
   4. Aerobraking should be managed so that the vehicle ends up
      near the space station in a phase matching orbit.  Rendezvous.

Assuming the requirement in step 1 can be met, the kick motor need
only supply a delta-V of less than 1 km/sec, and perhaps only
a few hundred m/sec.   Step 1 can be satisfied if the station is in
near equatorial orbit and the launcher's latitude is not too high, or if
the station is in polar orbit and the launcher fires payloads to orbits
with apogees above the north pole.

It seems wasteful to dissipate so much energy in aerobraking.  Better to
put the station itself in higher orbit.  A particularly attractive target
is highly eccentric earth orbit (HEEO).  There's a problem, however:
the payloads end up in orbits with major axes pointing in different
directions, depending on the time of launch.  To avoid this, launch the
vehicles into polar HEEO.  Kind of a strange orbit, but it might avoid
the worst of the radiation belts.  Perhaps Alaska would be a good place
for the launcher.

HEEO is ideal for the launch and recovery of interplanetary spacecraft.
It is nearly out of Earth's gravity well, but allows spacecraft to change
their velocities near the Earth, where the use of a rocket is most
efficient.  For example, a delta-V of only about 1.5 km/sec at perigee
in the proper HEEO will take you to Mars.

    Paul F. Dietz
    [e-mail]

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

Date:    Mon, 11 Jul 88 16:10 CDT
From: Kerry Stevenson <[e-mail]>
Subject: Mars Face (again)

I hate to bring this stuff up again, but ....

This morning, while chowing down some breakfast, I listened to an interview
taking place on "Canada AM" (the True North's version of Good Morning America)
with a spokesman from an organization known as the "Mars Project". The spokesman
explained that he represented an "unofficial group of scientists", which has
apparently been doing work on the data gathered by the Viking missions back
in 1976.  Their thinking is that NASA has not given enough thought to some
of the more unusual data, in particular the "face on mars".  The spokesman
explained that they had obtained the original transmission data from Viking and
had applied more up to date image enhancement software, thus giving a more
detailed look at this feature.

Several photos were shown during the interview. The first showed a wide angle
view of the "face" area, with the face in the upper right corner and a
suspicous bunch of hills in the lower left.  The spokesman suggested that
these "structures" (which were much larger than the face) were also
of great interest because of their tremendous symmetry.  (note- I didn't
think they were that symmetrical, but one could imagine large pyramids if
you closed one eye and had a few of your favorite brews first)  The next
two pictures were closeups of the face itself, and seemed quite a bit more
detailed than the previously available photos.  The photo showed a right
eye, nose, cheek, a faint hairline and a sort of built-up ring around the
whole mess.  The other "facial-closeup" was taken at a different sun angle,
some 35 degrees different than the other closeup.  It showed remarkably
similar features to the low angle photo, supposedly demonstrating that
there is actually a structure with these features, and that it is not
entirely due to lighting effects.

The final shot was the most interesting of the bunch.  It showed a 3-D
computer analysis of the face, based on the two views previously shown.
There were 16 views of the structure, and they were quite amazing.
It really looks like someone carved a face out of a hill. I thought that
the nose was interesting, since it did not "stick out", and was rather
flat against the rest of the face - exactly what one might expect if
you had carved out a face. The whole structure appeared to be close
to a square in shape, with rounded corners - again, very symmetrical.
Of course, some of the left side of the face was in darkness in both
shots and could not be shown in the 3-D views.

The spokesman explained that they had sent a representative (a Dr.
Brian O'Leary?) to Moscow last week to see if they could convince the
Soviets to have the Phobos probe take some pictures of the region
containing the face.  He expressed some doubt that the Soviets would
be able to accomodate them, as interplanetary schedules are usually
difficult to change with a week's notice.  However, he then said that
they would definitely be able to get a closer look at the face with
the american Mars Observer, which he said would be launched in 1992.
It's my understanding that the Mars Observer may be delayed until
sometime after that.

Contrary to what one may see in a newspaper from a grocery checkout
line, this guy seemed to be for real.  He didn't draw any conclusions
about this, other than that "these photos are extremely provocative,
and should be investigated further."

Can someone explain what the "Mars Project" is?  What other projects
are they working on?  Are they as real as they seem?  I also thought
that the Mars Face was a bunch of hooey, however, when you see these
new enhanced pictures you may want to reconsider your opinion.  I
don't believe that it is really a face, but I now think that
I'd at least like to see a couple of hi-res pictures of this
"structure" taken by new spacecraft.

                                           Kerry.

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

Date: 11 Jul 88 21:36:46 GMT
From: pioneer.arc.nasa.gov![e-mail]  (Eugene N. Miya)
Subject: Re: advance space news from June 6 AW&ST -- Pegasus!

In article <[e-mail]> [e-mail] (Henry Spencer) writes:
>> hidden subsidies: How much are OSC and Hercules paying for use of the
>> NASA B52?  How much are they paying for computing at Ames?
>
>This I don't know.  I would speculate that the B-52 is being provided on
>a basis of "until we have our own carrier aircraft, the customer has to
>supply it".  Ames is presumably involved in this for its own reasons, and
>may consider free computing time justified.

Actually, I brought this up, off the cuff.  There is some confusion
here.  This project isn't doing any computing at Ames.  There is a name
collision here, and this is the source of some confusion.
The B52 is also ours (down at Dryden), but I don't know how
reimbursement is done for this.  You were just lucky on this one.

Another gross generalization from

--eugene miya, NASA Ames Research Center, [e-mail]
  resident cynic at the Rock of Ages Home for Retired Hackers:
  "Mailers?! HA!", "If my mail does not reach you, please accept my apology."
  {uunet,hplabs,ncar,decwrl,allegra,tektronix}!ames!aurora!eugene
  "Send mail, avoid follow-ups.  If enough, I'll summarize."

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

Date: 11 Jul 88 04:07:40 GMT
From: attcan!utzoo![e-mail]  (Henry Spencer)
Subject: NASA support for industry

> >Remember that NASA *is*
> >charged with advancing aerospace technology for use by private industry.
>
> Has anyone told them this?  While I've seen evidence of an interest in
> airplanes, they don't seem to have done much to help with launchers.
> Or are they helping while the rest of the government works against them?

No, unfortunately.  NASA *is* officially supposed to help industry, in much
the same way that its predecessor NACA did.  (NACA's enormous contributions
to aviation are the single best argument *against* abolishing -- as opposed
to reorganizing -- NASA.  Yes, Virginia, governments can be helpful.)  The
aeronautics people at NASA have not forgotten this.  Unfortunately the space
people mostly have.  Note that the NASA people helping with Pegasus are
basically the aeronautics people.
--
Anyone who buys Wisconsin cheese is|  Henry Spencer at U of Toronto Zoology
a traitor to mankind.  --Pournelle |uunet!mnetor!utzoo! henry @zoo.toronto.edu

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

Date: 11 Jul 88 19:05:17 GMT
From: concertina![e-mail]  (Steve Hix)
Subject: Re: Von Braun quote

In article <[e-mail]>, [e-mail] (Paul Flaherty) writes:
> In article <[e-mail]> [e-mail] (Henry Spencer) writes:
> >--
> >Anyone who buys Wisconsin cheese is  |  Henry Spencer @ U of Toronto Zoology
> >a traitor to mankind.  --Pournelle   | {ihnp4,decvax,uunet!mnetor}!utzoo!henry
>     ^
>     |
>     \------    A curious comment, since the dairy industry supported the
>         Republican candidate in the last election...

This will make moe sense when you consider who is/was for a long time
the senior senator from Wisconsin...

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

Subject: Naming the Space Station
Date: Mon, 11 Jul 88 18:47:15 -0400
From: Fred Baube <[e-mail]>


Another vote for "Space Station Fred" !

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

Date: 11 Jul 88 22:05:30 GMT
From: pioneer.arc.nasa.gov![e-mail]  (Eugene N. Miya)
Subject: Re: postings from LARC (was none BITNET eh?)

I expect Mike Fischbein might answer this. He's from LARC.
Let me suppliment what he can tell you.

There are people at Langley who read the news (sci.space or space-digest
depending on your interface).  You probbaly will see an occasional
posting from JPL, Ames, etc.  Several years ago, when I was with the
Research Branch, I was given a charter to spend time reading net news
(up to 10% time).  So I had "official word" and I forwarded things
like when the Challenger blew up, etc.  Now, I sort of read for "fun."
You know, like the NSA guys. Why? Several reasons: we wanted to hire
some good people (network savvy, would you hire a computer person who's
never heard of the ARPAnet, Usenet, or BITNET? there's lots out there),
we frequently have needs for device drivers, etc.

There are several reasons for answers to your questions.  First, NASA is
not very well connected as far as networks go.  The guys who are doing
some of these are located in my old building.  I did some of this when I
was working at JPL (got their first LHDH as an example).  You were
probably searching a host table.  You may see a few GSFC hosts as well.
Getting from one machine to another is not a guarantee, additionally,
lots of machines are intentionally kept isolated.

There are other cultural factors which keeps lots of NASA in the dark:
lots of machines aren't networking stock: know of a TCP/IP for a Varian
620/f now Unisys V73 or V76s?).  NASA has hundreds of these as well as
Modcomp IVs, etc.  NASA as a civilian spinoff of the military also has
some paranoia about computers and computer networks.  Recent
computer/plane combination disasters, breakins, etc. don't help this.
There's lots of managers who have great fear of this stuff.  Who has the
computers?  Not the Public Information Office people, usually
researchers.  Did you think they have time for all the drivel on this
net?

If you are insulted by the term drivel, tough cookies, more than one
person has pointed this out.  I usually hit either the "n"ext or "r"eply
rather than follow up.  I can't answer every question, and I just skip
notes now after I get back from vacation.  You guys need a moderator, to
some extent, but it shouldn't be a NASA person.  Ted's also swamped.
Anyways, good researchers will tend to have their own lines of
communication.  There is some HEPnet and SPAN gatewaying, but recent
events are going to hurt a lot of this.  These guys are trying to do
work, but if they have to answer every question which gets fielded to
them about ozone layers, LA the Movie, etc. then you have just killed
a goose.  Anyway, my IRIS is down for the moment, so I can say this.

"Hope you can adjust," as Joan Baez once said.

Another gross generalization from

--eugene miya, NASA Ames Research Center, [e-mail]
  resident cynic at the Rock of Ages Home for Retired Hackers:
  "Mailers?! HA!", "If my mail does not reach you, please accept my apology."
  {uunet,hplabs,ncar,decwrl,allegra,tektronix}!ames!aurora!eugene
  "Send mail, avoid follow-ups.  If enough, I'll summarize."

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

Date: Mon, 11 Jul 88 18:14:09 CDT
From: [e-mail] (Bruce D. Wright)
Subject: Re: Space Suits

The important issue here may be that it takes about 3 psi (160 mm Hg) oxygen
partial pressure to maintain about 100 mm Hg oxygen partial pressure in the
alveoli of the lungs.  Below this partial pressure the blood does not saturate
with oxygen while passing through the lungs.  Trying to hold 3 psi pressure
in your lungs reletive to the pressure outside of your body would probably
cause an embolism to occur, not to mention that breathing extreme possitive
pressures like this would be REALLY exhausting.

Also, breathing pure oxygen at such low total pressure causes atelectasis to
occur.  This is alveoli collapse caused by the oxygen in the alveoli being
absorbed into the blood.  The carbon dioxide remaining in the alveoli doesn't
have enough pressure to withstand the blood pressure outside of the alveoli,
thus, they collapse.  Coughing can reinflate them, but this seems like a really
stressing environment, not to mention the constant worry about the vacuum
causing boils to raise in your skin in all those hard to cover places and the
hassle (and health risks) of necessary decompression for every EVA.  Adding
good old inert nitrogen will alleviate these health risks, although it adds its
own problems.

There is always a measure of trade-offs in any engineering design.  Loss of
mobility is a drag, but maybe the health risks are worse in a 'skin suit'.  If
it was me up there, I would want a full pressure suit that was engineered for
whatever mobility was possible, then make up the difference with good tools.


Bruce Wright
Agricultural Engineering
Texas A&M University

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

End of SPACE Digest V8 #295
*******************