Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V13_1/V13_130.ZIP/V13_130

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Subject: SPACE Digest V13 #130

SPACE Digest                                     Volume 13 : Issue 130

Today's Topics:
                Visiting NASA
             satellite prediction service
         Re: Satellite Imagery of Iraq/Kuwait
              Re: astronomical software
              Galileo Update - 02/04/91
              Magellan Update - 02/04/91
          Re: Hacking Spacecraft & ESA Publications
               Re: Liquid SCUBA

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
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Date: 2 Feb 91 01:46:41 GMT
From: usc!cs.utexas.edu!news-server.csri.toronto.edu!utgpu!utzoo!sq![e-mail]  (Mark Brader)
Organization: SoftQuad Inc., Toronto, Canada
Subject: Visiting NASA
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To: [e-mail]


People interested in visiting NASA sites may wish to check out the
February-March issue of "Air & Space / Smithsonian" magazine.
There's an 8-page pullout section with hours, phone numbers,
directions, and descriptions of what goes on at each location.

While I'm writing, I'll post their subscription information:
Box 53261, Boulder, CO, 80332-3261; price, US $18 per year
(6 issues), $24 outside US and possessions.  Single copies are
$3.50, if you can find a place that carries it.
--
Mark Brader            "*Nature*, Mr. Allnutt, is what we are put in
SoftQuad Inc., Toronto         this world *to rise above*."
utzoo!sq!msb, [e-mail]                -- The African Queen

This article is in the public domain.

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Date: 3 Feb 91 20:34:52 GMT
From: zaphod.mps.ohio-state.edu!usc!snorkelwacker.mit.edu!bloom-picayune.mit.edu![e-mail]  (Richard the Nerd)
Organization: Massachusetts Institute of Technology
Subject: satellite prediction service
Sender: [e-mail]
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Hi everyone,

Some of you might still remember me.  It must be a couple of years ago
now, but I used to send (by email) satellite predictions for many
people, on a weekly basis.  We all had lots of fun watching the Soviet
space station Mir, US spy satellites, and various other bright
objects.

Then, school kept me very busy and I stopped doing this.  But, to my
amazement, I kept getting notes from lots of people that they miss my
"service" and that I should start this again.  This had not stopped!
After such a long time, people are still interested.  SO:

I decided to do this again!  This is a note for all who are interested:
send me a note and sign up!

WHAT YOU CAN EXPECT: You can pick the satellites that you want to see
and every week I will email you predictions of their tracks across the
night sky.  You can then watch them with binoculars; the brighter
objects can also easily be seen with the unaided eye.  Also included
with your mailing will be a brief newsletter.  You will be encouraged
to participate in actively tracking certain objects such as classified
US spy satellites.

IF YOU ARE INTERESTED: If you have any questions concerning various
details, do not be afraid to ask.  If you are interested but are a
complete beginner, I will help you understand what's going on.  If you
are interested in receiving the mailings, you will need to send me
your:

Name
Email Address
Geographical location*
Time Zone
Whether Daylight Savings Time is used at your location and if so when
The satellites you would like to observe (up to 10)**

* If you live in a major town chances are I already have its latitude
and longitude.  Nevertheless, it will be fun for you to figure out
your latitude and longitude; I will need these to about 2 decimal
places (when expressed in degrees).  If you can figure these out, it
would make my job a lot easier.

** If you are a beginner and/or are not sure what you would like to see,
say so and I will put in several bright objects that are easy to observe.

I hope to hear from lots of you!

Rich

[e-mail]   (arpa net)

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Date: 4 Feb 91 15:17:44 GMT
From: psuvm!esoc![e-mail]  (Lutz Massonne)
Subject: Re: Satellite Imagery of Iraq/Kuwait
References: <[e-mail]>, <[e-mail]>
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Some days ago, they showed on German TV images of Kuwait taken from Mir.
In fact it was a film with rather high resolution, showing smoke trails
from (presumably) burning oil wells or refineries and stripes of oil
drifting into the sea.

Roads and areas with buildings were clearly visible.

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Date: 4 Feb 91 15:56:51 GMT
From: usc!cs.utexas.edu!ut-emx![e-mail]  (Srinivas Bettadpur)
Organization: Center for Space Research, U of Texas at Austin, Austin, Texas
Subject: Re: astronomical software
References: <[e-mail]>
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In article <[e-mail]> [e-mail] (Paul Blase) writes:
>One item:  "ORBIT.  ORBIT is a working orbital simulator similar to those
>used by NASA to plan and monitor spaceflights in near-earth and lunar
>trajectories....the simulator will reproduce almost any real-life
>trajectory wihin a half million miles of earth with sufficient accuracy to
>permit serious research....
     Howdy,
         Some time back, I had asked for the applications for the
orbit prediction programs, and some kind souls had been good enough
to reply.  I have a couple of additional questions :  How accurately
can a program like the one described above predict the orbits ?
Also, for a typical user of such programs (presumably in conjunction
with the orbital elements posted on this net, no ?), what is the
acceptable accuracy, and more importantly, for what period are
these orbits predicted using these programs ?
      Thanks in advance
                                   Srinivas Bettadpur
--
Srinivas Bettadpur           Internet : [e-mail]
P.O. Box 8520, Austin, Tx. 78713-8520, U.S.A.  Tel. [phone]
BITNET : aoab314@uthermes

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Date: 4 Feb 91 19:54:54 GMT
From: sdd.hp.com!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Organization: Jet Propulsion Laboratory, Pasadena, CA.
Subject: Galileo Update - 02/04/91
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                        GALILEO STATUS REPORT
                          February 4, 1991

     The Galileo spacecraft successfully completed the planned sun acquisition
on February 2.  Today, spacecraft activities will consist of a cruise science
memory readout for the DDS (Dust Detector) and MAG (Magnetometer) instruments,
a planned sun acquisition, and a USO (Ultra Stable Oscillator) calibration
test.  The Command Loss Timer will also be reset to 240 hours and and the Star
Scanner high voltage will be turned off to protect its photocathode from Earth
light.  Earth will appear as a bright body to the Star Scanner from February 6
to February 24.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|      Ron Baalke         | [e-mail]
     | | | |  __ \ /| | | |      Jet Propulsion Lab |
  ___| | | | |__) |/  | | |___   M/S 301-355        | It's 10PM, do you know
 /___| | | |  ___/    | |/__ /|  Pasadena, CA 91109 | where your spacecraft is?
 |_____|/  |_|/       |_____|/                      | We do!

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Date: 5 Feb 91 00:56:38 GMT
From: usc!elroy.jpl.nasa.gov!forsight!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Organization: Jet Propulsion Laboratory, Pasadena, CA.
Subject: Magellan Update - 02/04/91
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                          MAGELLAN STATUS REPORT
                             February 4, 1991

     The Magellan spacecraft and its radar system are performing nominally.
All STARCALS (star calibrations) and DESATS (desaturations) over the weekend
were successful.  The attitude updates are averaging about .040 degrees since
the reference star pair was changed, which is somewhat larger than earlier
update averages but well within specification.

     Temperatures of various spacecraft subsystems have been increasing as the
sun angle changes.  During the weekend the battery #1 temperature crept back
up to a peak of 20 degrees Celsius.  The sun angle will be perpendicular to
the battery compartment today.

     Software is being developed to counter the increasing temperatures,
either to "hide" behind the High Gain Antenna or to alternate sides of the
spacecraft exposed to the Sun.  The "hide" maneuvers which will be needed
ultimately in cycle 2 will cause a loss of 10% to 60% of the radar data on
each orbit.

     The P1033 "tweak" on February 1 (a routine update of the radar mapping
sequence and parameters) was successful.  No commanding of the spacecraft is
planned for today.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|      Ron Baalke         | [e-mail]
     | | | |  __ \ /| | | |      Jet Propulsion Lab |
  ___| | | | |__) |/  | | |___   M/S 301-355        | It's 10PM, do you know
 /___| | | |  ___/    | |/__ /|  Pasadena, CA 91109 | where your spacecraft is?
 |_____|/  |_|/       |_____|/                      | We do!

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Date: 3 Feb 91 23:41:37 GMT
From: netcom![e-mail]  (Eddie Goletz)
Organization: Netcom- The Bay Area's Public Access Unix System {408 241-9760 guest}
Subject: Re: Hacking Spacecraft & ESA Publications
References: <Added.wbd9srq00UkTAlhE9=@andrew.cmu.edu>
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To: [e-mail]

In <Added.wbd9srq00UkTAlhE9=@andrew.cmu.edu> Bill Higgins writes:

>Teenage crackers who want to make illicit use of ESA spacecraft.

Gee Bill, I've never seen a cracker over 12 years old. :-)

>How about it?  Could outsiders seize control of Giotto, Olympus, or
>Hipparcos?  What equipment would it take?  Are commands encrypted?
>Has anybody ever tried this? I presume military satellites are
>protected against this sort of thing, but what about civilian ones?
>Is there enough interest to start a sci.space.pirate newsgroup? (-:

I've heard some old war stories about funny things that have happened
to U.S. satellites.  One story I was told was when a tracking station
had it's antenna aimed at it's borsite tower, which is a receiver used
for calibrating the antenna.  It's power amp was off, so it was only
radiating a few watts.  It turned out that there was a satellite in
it's direct line of sight.  When that satellite had it's next routine
health and status check, the ground controllers were, shall we say,
somewhat surprised to find the satellite in a different configuration
than they left it.

Another story I heard was about some routine support for a geostationary
satellite.  It was a very long support, and 12 hours into the support
the ground controllers realized that the antenna was pointing several
degrees off from what they expected.  It turned out that they were up
on the wrong satellite!  Whoops!

I have also heard that the U.S. military has realized that 90% of it's
communications depend on civilian satellites, so they have convinced
manufacturers to put some unclassified (but still controlled)
encryption/decryption devices on their non-military satellites.

Could anyone gain control of a satellite?  Well, maybe.  Here is another
question for you. Suppose someone in the U.S. sends some commands to
an ESA satellite.  Would this person have broken any significant laws?
Could he or she be arrested?

Eddie Goletz
[e-mail]  or [e-mail] after Feb 11

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Date: Mon, 4 Feb 91 13:02:13 EST
From: John Roberts <[e-mail]>
Organization: National Institute of Standards and Technology
    formerly National Bureau of Standards
Disclaimer: Opinions expressed are those of the sender
    and do not reflect NIST policy or agreement.
To: [e-mail]
Subject: Re: Liquid SCUBA


>From: [e-mail] (Anthony DeBoer)
>Subject: Re: liquid SCUBA -- possible?
>Date: 29 Jan 91 01:03:16 GMT
>Organization: Geac J&E Systems Ltd.

>When I first heard of such things, it was in connection with space launch
>technology.  One possible launch system would use a variation on a magnetic
>coil gun, or rail gun, or some such thing, mounted on the side of a mountain
>near the equator.  It would shoot a payload at about 1000 G initial
>acceleration into earth orbit.  This is great for payloads that can take that,
>but you or I can't, since the front of your chest would collapse right into
>your lungs under that much gravity, and you'd wind up looking generally like
>high-tech road kill.  The idea they had was to use liquid breathing, with some
>complicated solution, to fill your lungs and breathing spaces, then fill your
>sinuses and middle ears with some neutral solution and put you inside a tank
>of water, such that everything would be at the same density.  Then they could
>shoot you out of their cannon without it bothering you.

>Anthony DeBoer - NAUI #Z8800                           [e-mail]
>Programmer, Geac J&E Systems Ltd.             uunet!jtsv16!geac!gjetor!adeboer
>Toronto, Ontario, Canada             #include <std.random.opinions.disclaimer>

I saw this demonstrated on a TV science show years ago. The details as I recall
them were as follows:

A glass-walled tank was shown, filled with a colorless, transparent liquid.
A white mouse was already in the liquid at the beginning of the shot. An
aquarium bubbler was running, presumably to provide the necessary oxygen.
The mouse was (I think) bouncing along the bottom of the tank, looking
around. It did not seem particularly distressed. After a minute or two,
the mouse was removed from the tank. It sneezed a few times, and started
breathing air.

If the mouse was indeed more dense than the liquid, that might imply that
the liquid had a fairly low density (though it might also sink in water with
no air in its lungs). I got the impression that it was a relative of freon,
which would seem to match Mr. Kludge's statement.
.....................

>From: [e-mail] (Mark Gabriele )
>Subject: Re: liquid SCUBA -- possible?
>Date: 29 Jan 91 19:04:35 GMT

>[e-mail] (Henry Spencer) writes:
>>Well, I don't know as I'd want to be the first person to try it. :-)  There
>>are still density differences; for example, your bones are denser than the
>>surrounding tissue.  Run the acceleration up high enough and injury will
>>still result.  I have no feel for where trouble starts, though.

I would imagine 10G would probably be workable (humans can sustain this with
flight suits, etc. already but only for brief periods), and possibly 20
or 30G. At 1000G the body would almost certainly tear itself apart.
Another important factor in human tolerance of launch conditions is the
derivative of acceleration, also called "jerk".

>...and I should point out that although the trials on humans may not
>have been done yet (it might be urban legend), the trials on rats and
>mice (which I have personally witnessed) showed that the lungs are not
>designed to breath fluids of that density.  Basically, the diaphragm
>muscle gets too tired to continue breathing after a fairly short time
>(I don't know what this time restriction would be for a human).  So,
>after you're in the capsule, they'd better not delay the countdown....
>=Mark ([e-mail])

As Peter Scott pointed out, some kind of mechanical aid should help. I
would favor some combination to minimize negative pressure on the lungs.
I think among possible health concerns would be effects on the natural
surfactants in the lungs that keep them from collapsing in air.

For very high accelerations, there's another possibility - freezing.
Recent studies have shown that some surprisingly advanced animals get
through the winter by freezing solid. (Actually, it's the intercellular
fluid that freezes - the liquid within the cells remains unfrozen.)
Maybe 100G or more would be practical for frozen creatures.
    John Roberts
    [e-mail]

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End of SPACE Digest V13 #130
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