Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_4/V16NO457.TXT

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Date: Wed, 14 Apr 93 05:05:49
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #457
To: Space Digest Readers
Precedence: bulk


Space Digest                Wed, 14 Apr 93       Volume 16 : Issue 457

Today's Topics:
                  "Temporary orbits" for Mars moons?
                                <None>
  ASAT wasn't orbital (was Re: Question- Why is SSTO  Single Stage)
                  CIS air launched booster projects
          Comet in Temporary Orbit Around Jupiter? (2 msgs)
        Computer Program Will Catalog Astronomical Sky Survey
 How to get there? (was Re: Comet in Temporary Orbit Around Jupiter?
 How to get there? (was Re: Comet in Temporary Orbit Around Jupiter?)
                  Question- Why is SSTO Single Stage
             Two-Line Orbital Element Set:  Space Shuttle
             What if the USSR had reached the Moon first?
             Will the launch be visible from NJ? (2 msgs)

    Welcome to the Space Digest!!  Please send your messages to
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----------------------------------------------------------------------

Date: 13 Apr 93 20:41:35 GMT
From: James Thomas Green <[e-mail]>
Subject: "Temporary orbits" for Mars moons?
Newsgroups: sci.space,sci.astro,alt.sci.planetary

Is the "temporary orbit" theory accounting for the comet about
Jupiter similar to how Demios and Phobos got captured about
Mars?  If not, what is different between the Comet at Jupiter
and the Martian moons?


/~~~(-: James T. Green :-)~~~~(-: [e-mail] :-)~~~\
| "I believe that this nation should commit itself to achieving    |
| the goal, before this decade is out, of landing a man on the     |
| Moon and returning him safely to the Earth."            |
|                  <John F. Kennedy; May 25, 1961>         |

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

Date: 13 Apr 93 18:43:50 -0600
From: Bill Higgins-- Beam Jockey <[e-mail]>
Subject: <None>
Newsgroups: sci.space,sci.astro,alt.sci.planetary

In article <[e-mail]>, [e-mail] (ERIC B. GOOLD) writes:
[quoting me]
>>While you're at it, comet experts, explain how a comet gets into
>>Jovian orbit to begin with!
>
> I'm not an expert, but I'd say that it would be something like the slingshot
> technique, but the opposite. Instead of stealing energy from the Jupiter-Sun
> orbit it would be giving energy to it.

Eric Goold and Ron Baalke both gave rational explanations for this.
By the way, it sounds like breakup and non-gravitational forces have
nothing to do with the capture.

I guess what's bothering me is the phase space.  The seat of my pants
(more politely known as "my physics intuition") tells me that a comet
must occupy a narrow range of velocities and
nearest-approach-to-Jupiter distances in order to end up being bound
to Jupiter.  This seems like a very rare event, not something that
would be observed two or three times in a twenty-year period.  Of
course, the seat of my pants has been wrong before.

If cometary capture is fairly common, the phase space must be bigger
than I think.  I'd like somebody to tell me why.

I have looked in a couple of U. Az. Press books but they refer me to
books and articles not handy in the Fermilab library.   The problem is
connected to the origin of the Trojan asteroids. I note that some
experts on this have written a book:  *Long-Term Evolution of
Short-Period Comets*, by Carusi, Kresak, Perozzi, and Valsecchi,
published in 1985 by Adam Hilger, Ltd.  Remember the Firesign Theatre
radio station that broadcast "Morning Concert of Afternoon Showtime
Favorites?"

I don't think my interest in this matter is large enough to drive into
Chicago to dig the answer out of a better library.  This might change
if Brian Marsden announces that the thing is definitely captured and
will be around long enough for Galileo to take a peek at it!  Then I
will have to explain cometary capture to all my friends and relatives.

Bill Higgins, Beam Jockey         | "I'm gonna keep on writing songs
Fermilab                          | until I write the song
Bitnet:      [e-mail]  | that makes the guys in Detroit
Internet:  [e-mail]  | who draw the cars
SPAN/Hepnet:      43011::HIGGINS  | put tailfins on 'em again."
                                            --John Prine

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

Date: 13 Apr 93 19:44:55 -0600
From: Bill Higgins-- Beam Jockey <[e-mail]>
Subject: ASAT wasn't orbital (was Re: Question- Why is SSTO  Single Stage)
Newsgroups: sci.space

In article <[e-mail]>, [e-mail] (Dennis Newkirk) writes:
[on dropping ICBMs out of airplanes...]
> There was an interesting comment about this kind of launch system at the
> World Space Congress last year. A military type researcher said that
> technology was close or possible to allow a aircraft to be outfitted
> with  a propellant production plant (assumed LH and LOX) and the empty
> booster. The idea is the plane takes off, fuels the missile in flight
> and launches it and returns to base. This leaves no trace of propellant
> production or launch facilities in the country of origin. Of course
> you have to get the missile and special aircraft somewhere...

This sounds like a *great* plot for a Jonny Quest episode.  (No, I
didn't catch the new JQ movie last week.  How was it?)

CAPTAIN BILL'S CHICAGO TOURS             Bill Higgins
 See the Loop by Submarine!              Fermilab
Shopping?  Take our convenient           [e-mail]
Bathyscaphe to Marshall Field's!         [e-mail]
[it's been one year since the Flood, I thought I'd use this .sig
for nostalgic effect...]

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

Date: Tue, 13 Apr 1993 18:40:48 GMT
From: Dennis Newkirk <[e-mail]>
Subject: CIS air launched booster projects
Newsgroups: sci.space

Overview of current Russian work in air launched space boosters.

This is by no means a complete list. References provided are quick and dirty
and not comprehensive! There are many more sources and much more information
available.

Interim HOTOL

Joint discussion on using a AN-225 (or 8 engined modification) to carry a
conventionally engined British HOTOL to 10,000 meters for release.  Initial
studies were said to be favorable.[1]


MAKS (Multipurpose Aerospace System)

Gleb Lozino-Lozinsky, Gerneral Designer Molnyia NPO, is trying to sell a 250,000 kg.
space plane and external tank combination, air launched from the AN-225. Named Molniya,
VMS [universal reusable spacecraft], Mayak or MAKS).  Unmanned payload is 8000 kg,
manned 7000 kg. Propellant would be a LOX-Hydrogen-Kerosene mix using new RD-701
engine.[2] (Also See article in the latest Spaceflight magazine. This project
may eventually replace ESA's Hermes)


Space Clipper

Proposed from the Ukraine's NPO Yuzhnoye.  This would be a  3-4 stage rocket, air
launched from a heavily retrofitted AN-124SC aircraft.  The stages include
(#1)210,000 kg, (#2)107,000 kg, (#3)21,000 kg, (#4)6000 kg, and (#5)2000 kg thrust
units. Possible combinations include 1234, 2234, 234, 1235, 2235,
235. Launch time after payload integration is 10-15 hours, take-off weight
from 392-365,000 kg., range to launch 7-9000 km, cruise speed 800-850 km/hr,
launch altitude 10-11000 kg.  Payload for 1235 is 1750 kg, 2235 is 1150 kg,
235 is 700 kg, to a 200 km circular 90 degree inclination orbit, or 1234 is
800 kg, 2234 is 485 kg, 234 is 150 kg. to a 150 x 36000 km equatorial orbit.
Accuracy is 3.5 km, 2.5 sec., 2 min. inclination.  Design reliability 95%.
The aircraft would be equipped with air purification and thermo regulation systems
to support the payload and have GPS for navigation.  Launched from customers
territory at appropriate azimuth for inclination.  Booster is constructed from any
of 5 standard sized solid rocket stages.  The booster would be load on to the
An-124SC at the airfield at Dnepropetrovsk would be loaded and flown to the customer
for payload integration throught the front hatch of the An-124SC.  Once at the
launching point the booster is pulled out the back hatch on a launching cradle by
parachute and once clear the parachute detaches and the rocket fires.
{{Also : The SS-18 ICBM was offered for commercial space launches, conventionally
launched, in 1992 by the Yuzhnoye NPO. Diameter 3 m, length 34.3 m, inside usable
payload shroud diameter 2.7 to 2.52 m, and 2.91 m long (possible increase to 5.91 m).
Launch weight is 210,000 kg., Payload to 200 km circular orbit at 90 degree inclination
is 4000 kg. (3.5 km, 2.5 sec, 2 min inclination), propellants are nitrogen
tetroxide and UDMH, first stage thrust is 460,000 kg, second stage 77,000 kg, third
stage 2,800 kg.}} [4]


Burlak

Proposal from Russia's NPO Raduga.  This would use a small all solid fuel launch
vehicle air launched from a Tu-160 BlackJack bomber.   It would be capable of
putting about 500 Kg into LEO.[4]

----------
References

[1] Kandebo, Stanley, W. "Spaceplane Conference Highlights International Hypersonic
    Programs." Aviation Week & ST, Nov. 12, 1990, pp. 68

[2] "International Partners for Soviet Air-Launched Spaceplane" Spaceflight, Vol. 32,
    May, 1990, pp. 146

[3] "Rocket Space Transportation Systems Produced by Yuzhnoye Rocket-Space Association",
    by YA Smetanin, IAF-92-0862, Aug, 28, 1992

[4] [e-mail] (Wales Larrison), "Comercial Space News #13",
    Tue, 28 Jan 92 01:17:21 PST, Organization: Universal Electronics Inc. (Public access BBS)
----------

Dennis Newkirk ([e-mail])
Motorola, Land Mobile Products Sector
Schaumburg, IL

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

Date: Tue, 13 Apr 1993 22:49:23 GMT
From: Henry Spencer <[e-mail]>
Subject: Comet in Temporary Orbit Around Jupiter?
Newsgroups: sci.space,sci.astro,alt.sci.planetary

In article <[e-mail]> [e-mail] (Frances Teagle) writes:
>This concept of a temporary orbit is new to me, what mechanism enables
>a comet to break free from Jovian orbit, once is has strayed into it?

Wrong question.  It arrived with enough energy to escape; the question
is, why does it stick around for a while?

The answer is that you're trying to apply two-body intuition in an area
where it breaks down.  In a distant orbit around Jupiter, you cannot
ignore the effect of the Sun, and you cannot just treat it as minor
perturbations to a basically Jupiter-centered orbit.  To get accurate
results, you have to work with a three-body problem, and three-body
dynamics are vastly more complex than two-body dynamics.  If you insist
on taking a Jupiter-centered perspective, such orbits have to be thought
of as massively perturbed, unlikely to do the same thing twice in a row,
and quite capable of turning into escape trajectories without warning.

Throw in complications like tidal effects, the multi-body interactions
in a comet nucleus that's partially broken up, and the possibility of
interactions with other objects orbiting Jupiter, and it's not hard to
figure out why the behavior can be very complex.
--
All work is one man's work.             | Henry Spencer @ U of Toronto Zoology
                    - Kipling           |  [e-mail]  utzoo!henry

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

Date: Wed, 14 Apr 1993 01:33:53 GMT
From: [e-mail]
Subject: Comet in Temporary Orbit Around Jupiter?
Newsgroups: sci.space,sci.astro,alt.sci.planetary

In article <[e-mail]>, [e-mail] (Henry Spencer) writes:
> In article <[e-mail]> [e-mail] (Frances Teagle) writes:
>>This concept of a temporary orbit is new to me, what mechanism enables
>>a comet to break free from Jovian orbit, once is has strayed into it?
>
> Wrong question.  It arrived with enough energy to escape; the question
> is, why does it stick around for a while?
>
Dance of the Planets spends a good deal of time studying the Gehrels 3
temporary capture.  While it is difficult to draw the "orbit" in text, I'll
try:

 -------_______
               -------_______
                             -------_______
                                           -------_______
                                                          ----___
                                       _______  ------- __        ---__
                  __________----------                   J_ -     ---
   _____----------                        ___________-----  ___ ---
___                              ____-----           ____---
                                     -----______-----




Hope this helps...the above drawing is very crude, I'm afraid.  For a
_much_ better analysis, see Dance or some other orbital simulation
package that can handle the calculations involved.

The Dance manual references the book A. Carusi and G. Valsecchi,
_Asteroids_ .


John Garland
[e-mail]

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

Date: 13 Apr 1993 20:35 UT
From: Ron Baalke <[e-mail]>
Subject: Computer Program Will Catalog Astronomical Sky Survey
Newsgroups: sci.space,sci.astro

Charles Redmond
Headquarters, Washington, D.C.                     April 13, 1993
(Phone:  [phone])

Jim Doyle
Jet Propulsion Laboratory, Pasadena, Calif.
(Phone:  [phone])

RELEASE:  93-067

COMPUTER PROGRAM WILL CATALOG ASTRONOMICAL SKY SURVEY

     Scientists at NASA's Jet Propulsion Laboratory (JPL) and the
California Institute of Technology (Caltech), both in Pasadena,
Calif., announced today that they have developed a computer
software system to catalog and analyze the estimated half billion
sky objects in the second Palomar Observatory sky survey.

     The survey of the northern sky includes more than 3,000
digitized photographic plates produced by Palomar, located in San
Diego.

     Drs. Usama Fayyad and Richard Doyle of JPL said the system,
called Sky Image Cataloging and Analysis Tool (SKICAT), will be
delivered to Caltech this month.  SKICAT is based on state-of-
the-art machine learning, high performance database and image
processing techniques.

     Caltech astronomer Professor S. Djorgovski said each
photographic plate is being digitized into 23,040 by 23,040-pixel
images at the Space Telescope Science Institute, Baltimore.  The
resulting data set will not be surpassed in quality or scope for
the next decade, he said.

     "The sky object classification task is manually forbidding.
The plates contain hundreds of millions of sky objects.  Humans
are unable to visually process the fainter objects in the
survey," Djorgovski said.

     Fayyad said the core of the new system includes two
integrated machine learning mathematical formulas, called
algorithms.  These algorithms automatically produce decision
trees for the computer based on astronomer-provided training data
or examples.  A machine learning program learns to classify new
data based on training data provided by human experts.

     Caltech astronomer Nick Weir and Fayyad said SKICAT has a
correct sky object classification rate of about 94 percent, which
exceeds the performance requirement of 90 percent needed for
accurate scientific analysis of the data.

     By contrast, Fayyad said, the best performance of a
commercially available learning algorithm was about 75 percent.
By training the learning algorithms to predict classes for faint
astronomical objects on the survey plates, the algorithms can
learn to classify objects that actually are too faint for humans
to recognize.

     The training data for faint objects was obtained from a
limited set of charge coupled device images taken at a much
higher resolution than the survey images, Weir said.

     The SKICAT system will produce a comprehensive survey
catalog database containing about one-half billion entries by
automatically processing about three terabytes (24 trillion bits,
8-bits to a byte) of image data.

     Since SKICAT can classify sky objects that are too faint for
humans to recognize, the SKICAT catalog will contain a wealth of
new information not obtainable using traditional cataloging
methods, Weir said.  Because sky objects up to one visual
magnitude fainter now can be processed, the number of classified
catalog entries will be approximately three times larger than has
been possible so far with other techniques.

     "Some historical sky object classification tasks performed
over a period of years could now be achieved in a few hours,"
Weir said.

     One major benefit of this program includes freeing
astronomers from the tedium of an intensely visual and manual
task so they may pursue more challenging analysis and
interpretation problems, according to Djorgovski.

     "This is an excellent example of the use of machine learning
technology to automate an otherwise infeasible task of dealing
with an amount of data that is simply overwhelming to humans,"
Fayyad said.  "SKICAT represents a new generation of intelligent
trainable tools for dealing with the huge volumes of scientific
image data that today's instruments collect."

     "We view SKICAT as a step towards the development of the
next generation of tools for the astronomer of the turn of the
century and beyond," Djorgovski said.

-end-
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | [e-mail]
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Being cynical never helps
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | to correct the situation
|_____|/  |_|/       |_____|/                     | and causes more aggravation
                                                  | instead.

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

Date: 13 Apr 93 19:22:39 -0600
From: Bill Higgins-- Beam Jockey <[e-mail]>
Subject: How to get there? (was Re: Comet in Temporary Orbit Around Jupiter?
Newsgroups: sci.space,sci.astro,alt.sci.planetary

In article <[e-mail]>, [e-mail] (ERIC B. GOOLD) writes:
>In article <[e-mail]>, [e-mail] (Bill Higgins-- Beam Jockey) writes:
>>While you're at it, comet experts, explain how a comet gets into
>>Jovian orbit to begin with!
>
> I'm not an expert, but I'd say that it would be something like the slingshot
> technique, but the opposite. Instead of stealing energy from the Jupiter-Sun
> orbit it would be giving energy to it.

Eric Goold and Ron Baalke both gave rational explanations for this.
By the way, it sounds like breakup and non-gravitational forces have
nothing to do with the capture.

I guess what's bothering me is the phase space.  The seat of my pants
(more politely known as "my physics intuition") tells me that a comet
must occupy a narrow range of velocities and
nearest-approach-to-Jupiter distances in order to end up being bound
to Jupiter.  This seems like a very rare event, not something that
would be observed two or three times in a twenty-year period.  Of
course, the seat of my pants has been wrong before.

If cometary capture is fairly common, the phase space must be bigger
than I think.  I'd like somebody to tell me why.

I have looked in a couple of U. Az. Press books but they refer me to
books and articles not handy in the Fermilab library.   The problem is
connected to the origin of the Trojan asteroids. I note that some
experts on this have written a book:  *Long-Term Evolution of
Short-Period Comets*, by Carusi, Kresak, Perozzi, and Valsecchi,
published in 1985 by Adam Hilger, Ltd.  Remember the Firesign Theatre
radio station that broadcast "Morning Concert of Afternoon Showtime
Favorites?"

I don't think my interest in this matter is large enough to drive into
Chicago to dig the answer out of a better library.  This might change
if Brian Marsden announces that the thing is definitely captured and
will be around long enough for Galileo to take a peek at it!  Then I
will have to explain cometary capture to all my friends and relatives.

Bill Higgins, Beam Jockey         | "I'm gonna keep on writing songs
Fermilab                          | until I write the song
Bitnet:      [e-mail]  | that makes the guys in Detroit
Internet:  [e-mail]  | who draw the cars
SPAN/Hepnet:      43011::HIGGINS  | put tailfins on 'em again."
                                            --John Prine

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

Date: Tue, 13 Apr 1993 20:51:07 GMT
From: "ERIC B. GOOLD" <[e-mail]>
Subject: How to get there? (was Re: Comet in Temporary Orbit Around Jupiter?)
Newsgroups: sci.space,sci.astro,alt.sci.planetary

[e-mail] (Bill Higgins-- Beam Jockey) writes:
>In article <[e-mail]>, [e-mail] (Frances Teagle) writes:
>> In article <[e-mail]> [e-mail] (Ron Baalke) writes:
>>
>>>Comet Gehrels 3, which was discovered in 1977, was determined to have
>>>been in a temporary Jovian orbit from 1970 to 1973.  Comet Shoemaker-Levy 1993e
>>>may remain in orbit around Jupiter long enough to allow Galileo to
>>>make some closeup observations.  The orbital trajectory for Comet
>>>Shoemaker-Levy is still being determined.
>>
>> This concept of a temporary orbit is new to me, what mechanism enables
>> a comet to break free from Jovian orbit, once is has strayed into it?
>
>While you're at it, comet experts, explain how a comet gets into
>Jovian orbit to begin with!
>
Hello,

I'm not an expert, but I'd say that it would be something like the slingshot
technique, but the opposite. Instead of stealing energy from the Jupiter-Sun
orbit it would be giving energy to it. If enough enough energy is transfered
to the Jupiter-Sun orbit it won't have enough energy to escape the
comet-Jupiter orbit. ACK! 3 body problems are pretty bad, it's kinda tough
to treat them as a couple 2 body orbits... (Note: the Jupiter-sun orbit will
not change much due to the large amount of energy associated with it... Give
or take a few comets will make no difference...)

Later, when the comet is in the right position/trajectory it'll get some energy
back and escape...

                        Eric Goold

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

Date: Tue, 13 Apr 1993 20:38:24 GMT
From: Dave Dodson <[e-mail]>
Subject: Question- Why is SSTO Single Stage
Newsgroups: sci.space

I think the obvious answer to the question is:

Wouldn't it be silly to use the acronym SSTO, meaning
"Single Stage To Orbit" for a multistage vehicle?

Dave

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

Date: Tue, 13 Apr 1993 23:43:14 GMT
From: TS Kelso <[e-mail]>
Subject: Two-Line Orbital Element Set:  Space Shuttle
Newsgroups: sci.space

The most current orbital elements from the NORAD two-line element sets are
carried on the Celestial BBS, [phone], and are updated daily (when
possible).  Documentation and tracking software are also available on this
system.  As a service to the satellite user community, the most current
elements for the current shuttle mission are provided below.  The Celestial
BBS may be accessed 24 hours/day at 300, 1200, 2400, 4800, or 9600 bps using
8 data bits, 1 stop bit, no parity.

Element sets (also updated daily), shuttle elements, and some documentation
and software are also available via anonymous ftp from archive.afit.af.mil
(129.92.1.66) in the directory pub/space.

STS 56
1 22621U 93 23  A 93103.35416666  .00047945  00000-0  13817-3 0   198
2 22621  57.0042 155.1950 0004792 279.7934 331.5599 15.92686423   812
1993 023B
1 22623U 93 23  B 93103.05929260  .00066652  00000-0  19123-3 0    75
2 22623  57.0035 156.5616 0004330 275.5582  84.5080 15.92646940   754
--
Dr TS Kelso                           Assistant Professor of Space Operations
[e-mail]                    Air Force Institute of Technology

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

Date: Tue, 13 Apr 1993 22:06:00 GMT
From: Frank - Hardware Hacker - Borger <[e-mail]>
Subject: What if the USSR had reached the Moon first?
Newsgroups: alt.history.what-if,sci.space

In article <[e-mail]>, [e-mail] (ChaOs) writes...
>In article <dxb105.734495289@virgo>, [e-mail] (David Bofinger) writes:
>> [e-mail] (ChaOs) writes about the military application
>> of a lunar base:
>>
>>> Well, ever read (for example) Robert Heinlein's _The Moon is a Harsh
>>> Mistress_?  A lunar colony was able to do a frightening amount of
>>> damage just by throwing rocks at earth.
>
>Just to get off the subject a bit, having _one_ computer that controlled just
>about everything on the Moon from life support to transportation to calculating
>flight paths means that the computer would _have_ to be tremendously complex.
>That's why Mike woke up in the first place.  Now back to the topic:

    Staying off the subject, Heinlein also miscued badly in the story saying
    that when Mike died, all the banks went back to using abacuses. Saw a
    quote the other day that if we had to replace all the computational
    power just used by computers in banking with humans with mechanical
    calculators or abacuses or whatever, it would take the entire population
    of the US working 40 hour weeks.

    Until the Russians had enough cloned 360's, PDP11's and VAX's, they
    didn't have the compute power to do a manned moon landing. Their
    main thrust (pun intended,) has been toward high-lift capabilities,
    near-earth expeditions, etc.

    There later stuff is quite sophisticated, (unmanned shuttle flight
    implies they had nose-wheel under computer control, something NASA
    isn't doing yet.)

Frank R. Borger - Physicist     ___      George Halas had two heirs; one carried
Michael Reese - U of Chicago   |___      his seed and one carried his soul. ...
Center for Radiation Therapy   | |_) _   One can imagine the whisper of George
net: [e-mail]    | \|_)  Halas, rooting for his soul. -
ph: 312-791-8075 fa: 791-2517       |_)                           Jeannie Morris

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

Date: 12 Apr 93 14:44:03 GMT
From: Peter Jarvis <phred!petej>
Subject: Will the launch be visible from NJ?
Newsgroups: sci.space.shuttle,sci.space

In article <[e-mail]> [e-mail] (Duke Briscoe) writes:
>
>... I
>would like to know how long after launch the solid rocket boosters and
>the external tank are dropped.  I was observing at about 1:35 EST or
>maybe a few minutes later.
>
The SRB's are dropped 2 minutes and 6 secs after launch and the
external tank about 8 1/2 mintes after launch.

Peter Jarvis..........





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

Date: 12 Apr 93 15:06:51 GMT
From: Peter Jarvis <phred!petej>
Subject: Will the launch be visible from NJ?
Newsgroups: sci.space.shuttle,sci.space

In article <[e-mail]> [e-mail] (Bob Egan) writes:
>
>2. after the main engine cutoff....i was VERY surprised to see the
>very bright white beacons it flashed at about 2-3 second rate.
>look like on on the back and one front. (or was I hullicinating ??)

You may have seen attitude thrusters firing. The Shuttle has no beacons.
It doesn't need them.

>3. as the shuttle got further down range( east and north), I was looking up
>its "rear' and watched the orange glow....if the main engine fuel burn ended at
>8:40'ish...(the flash and no more bright large flame)...and the
>solid rockets blew away earlier..what is the fuel for the engines at this
>point ?

After the ET is jettisoned, the 2 OMS engines in back are fired to get
the Shuttle in the proper orbit. Depending on what orbit they are inserting
into, they have 1 or 2 OMS burns to trim the orbit properly. If you saw
engines burning immediately after ET jettison, then they had an OMS 1 burn
followed by another later.

>now..was this a "fly w/ us and see the shuttle by a departing airline
>out of logan, or is this a chase plane for NASA" ????

It was probably neither. Departing airliners have dedicated routes to follow
with ground controllers telling when and where to turn. As far as I know,
NASA does not chase its ascending Shuttles.

>.....anybody know
>if the white strobes are on all through the mission?
>
>Bob

Again, there are no strobes on the Shuttle.

Peter Jarvis..........

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


From: James Thomas Green <[e-mail]>
Newsgroups: sci.materials,sci.space,poly.dept.materials
Subject: Microgravity Materials Research
Summary: Request for info for my Senior Project
Message-Id: <[e-mail]>
Date: 13 Apr 93 20:27:52 GMT
Sender: [e-mail]
Organization: California Polytechnic State University, San Luis Obispo
Lines: 35
Source-Info:  Sender is really [e-mail]
Source-Info:  Sender is really [e-mail]

For my senior project I'm doing a survey of the literature
regarding research into microgravity materials processing.  I've
already got a bunch of sources but I'd like to get some more
input here.

What I'd like to know is:

* What topics re microg materials do you consider a must-cover
  in a comprehensive review?

* What persons and/or researchers are currently doing the "hot"
  research?

* Who are the "historically important" persons in the field.
  I.e. if you write a paper on physics, you include Newton.  If
  you write a paper on metallurgy, you include Sorby.  Who are the
  biggies in Microg research?

* While it isn't exactly "scientific", I'd like to include a few
  cartoons which relate to the microgravity (zero gravity)
  environment).  If you've seen a comic strip in you newspaper,
  etc, I'd appreciate if you could send me a copy (or at least
  point out where it is so I can get it myself).  My address is:

     James T. Green
     P. O. Box 4754
     San Luis Obispo, CA  93403-4754

Thanks for any help you net.land folks can provide.

/~~~(-: James T. Green :-)~~~~(-: [e-mail] :-)~~~\
| "I believe that this nation should commit itself to achieving    |
| the goal, before this decade is out, of landing a man on the     |
| Moon and returning him safely to the Earth."            |
|                  <John F. Kennedy; May 25, 1961>         |

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End of Space Digest Volume 16 : Issue 457
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