Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V09_5/V9_556.TXT

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Date: Wed, 26 Jul 89 03:17:54 -0400 (EDT)
Subject: SPACE Digest V9 #556

SPACE Digest                                      Volume 9 : Issue 556

Today's Topics:
            Re: Apollo 12 (And Surveyor 3)
            Decaying Lunar Orbits
         Re: Magellan Status for 07/11/89 (Forwarded)
  Apollo-11 lunar experiment still useful after 20 years (Forwarded)
Re: Apollo-11 lunar experiment still useful after 20 years (Forwarded)
                TF-104
               Reminders for Old Farts
          News of the Week (well, Month) -19
----------------------------------------------------------------------

Date: 14 Jul 89 21:38:09 GMT
From: cs.utexas.edu!usc!elroy.jpl.nasa.gov!jpl-devvax![e-mail]  (Lee Mellinger)
Subject: Re: Apollo 12 (And Surveyor 3)

In article <[e-mail]> [e-mail] writes:
:In article <[e-mail]>, [e-mail]
:(Lee Mellinger) writes:
:
:> The scoop housing was presented to Dr. William Pickering on his retirement as
:> Director of JPL in 1976.  (...)
:
:Isn't he Sir William Pickering?  I believe his knighthood came through his
:New Zealand citizenship; he initially came from there for graduate(?) studies
:at CALTECH.
:
:  Phillip MacQueen                  McDonald Observatory,

Not unless he got it in the last couple of years.  You may be
confusing him with another Dr. Pickering, an astronomer whom I know
was knighted.

Lee

"I'm the NRA"

|Lee F. Mellinger                 Caltech/Jet Propulsion Laboratory - NASA
|4800 Oak Grove Drive, Pasadena, CA 91109 818/393-0516  FTS 977-0516
|{ames!cit-vax,}!elroy!jpl-devvax!leem  [e-mail]

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

Date: 15 Jul 89 04:15:37 GMT
From: usc!cs.utexas.edu!ut-emx!hutto![e-mail]  (Henry Melton)
Subject: Decaying Lunar Orbits



I have seen a couple of references lately in the Apollo shows that the
returning upper portion of the LEM was abandoned in lunar orbit and then
later decayed to crash on the Lunar surface.  How fast is this orbital
decay, considering that there is no atmosphere to speak of?  Is there
some other mechanism that can cause such a fast decay?

--
Henry Melton ...!cs.utexas.edu!ut-emx!hutto!henry
1-512-8463241 Rt.1 Box 274E Hutto,TX 78634

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

Date: 15 Jul 89 22:29:18 GMT
From: bfmny0![e-mail]  (Tom Neff)
Subject: Re: Magellan Status for 07/11/89 (Forwarded)

In article <[e-mail]> [e-mail] (Peter E. Yee) writes:
>                     MAGELLAN WEEKLY STATUS ...
>
>     High temperature readings on the Solid Rocket Motor and the
>Rocket Engine Modules in some attitudes have been a problem. The
>operations team said Morton Thiokol made tests with a sample of
              ^^^^^^^^^^^^^^
>the Solid Rocket Motor core, and believes the temperature limit
                           ^^^^^^^^^^^^^^^^^
>can be raised from 34 C (93.2 F), to 70 C (158 F).
 ^^^^^^^^^^^^^

Just when you thought it was safe to make a midcourse correction...

(sound of slashing, roaring chainsaw)

HE LIVES!!  MORTON LIVES!!!

-----

TUESDAY THE 28TH, PART II:
MORTON TAKES MAGELLAN

...Coming soon to an Accident Review Board near you...

--
"My God, Thiokol, when do you     \\    Tom Neff
want me to launch -- next April?"  \\    uunet!bfmny0!tneff

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

Date: 17 Jul 89 21:45:09 GMT
From: trident.arc.nasa.gov![e-mail]  (Peter E. Yee)
Subject: Apollo-11 lunar experiment still useful after 20 years (Forwarded)

Paula Cleggett-Haleim
Headquarters, Washington, D.C.                      July 17, 1989

Mary A. Hardin
Jet Propulsion Laboratory, Pasadena, Calif.


RELEASE:  89-119

APOLLO-11 LUNAR EXPERIMENT STILL USEFUL AFTER 20 YEARS

     An experiment placed on the lunar surface 20 years ago by
the Apollo 11 astronauts continues to be used to study the Earth-
moon system by NASA's Jet Propulsion Laboratory, Pasadena,
Calif., and other scientific centers around the world.

     Scientists, who analyzed the data from the Laser Ranging
Retro-reflector Experiment, have observed, among other things,
that the moon is moving away from the Earth, tectonic plates of
the Earth are slowly drifting and the length of a day varies.

     The Laser Ranging Retro-reflector was designed to reflect
pulses of laser light fired from the Earth.  The idea was to
determine the round-trip travel time of a laser pulse from the
Earth to the moon and back again, thereby calculating the
distance between the two bodies to unprecedented accuracy.
Unlike the other scientific experiments left on the moon, this
reflector requires no power and is still functioning perfectly
after 20 years.

     The laser reflector consists of 100 fused silica half cubes,
called corner cubes, mounted in an 18-inch square aluminum
panel.  Each corner cube is 1.5 inches in diameter.  Corner cubes
reflect a beam of light directly back toward the point of
origin.  It is this fact that makes them so useful in Earth
surveying.

     The McDonald Observatory, Ft. Davis, Texas; the Lure
Observatory atop the extinct Haleakala volcano on the island of
Maui, Hawaii; and a third observatory in southern France near
Grasse, regularly send a laser beam through an optical telescope
and try to hit one of the reflectors.

     The reflectors are too small to be seen from Earth, so even
when the beam is correctly aligned in the telescope, actually
hitting a lunar reflector is quite challenging.  At the moon's
surface, the beam is roughly a mile wide and scientists liken the
task of properly aiming the beam to using a rifle to hit a moving
dime 2 miles away.

     Once the laser beam hits a reflector, scientists at the
observatories use sensitive filtering and amplification equipment
to detect the return signal.  The reflected light is too weak to
be seen with the human eye, but under good conditions, one photon
-- the fundamental particle of light -- will be received every
few seconds.

     Three more reflectors have since been left on the moon,
including two by later Apollo missions and one by the unmanned
Soviet Lunakhod 2 lander.  Each of the reflectors rest on the
lunar surface in such a way that its flat face points toward the
Earth.

     Continuing improvements in lasers and electronics over the
years have led to measurements accurate to approximately 1
inch.  Scientists know the average distance between the centers
of the Earth and the moon is 239,000 miles, implying that the
modern lunar ranges have relative accuracies of better than one
part in 10 billion.  This level of accuracy represents one of the
most precise distance measurements ever made and is equivalent to
determining the distance between Los Angeles and New York to one
fiftieth of an inch.

     During the last 20 years, scientists have used the orbit of
the moon and the lunar ranging sites to study events on Earth.
Lunar ranging has contributed to several scientific advances:

     *  Lunar ranging has helped determine the precise positions
of the observatories that send the laser beams.  Using these
positions, scientists can tell that the tectonic plates of the
Earth's crust are slowly drifting and the observatory on Maui is
seen to be moving away from the one in Texas.

     *  The atmosphere, tides and the core of the Earth cause
changes in the length of an Earth day -- the variations are about
one thousandth of a second over the course of a year.

     *  The familiar ocean tides raised on the Earth by the moon
have a direct influence on the moon's orbit.  Laser ranging has
shown that the moon is receding from the Earth at about 1.5
inches every year.

     *  Lunar ranging, together with laser ranging to artificial
Earth satellites, has revealed a small but constant change in the
shape of the Earth.  The land masses are gradually changing after
being compressed by the great weight of the glaciers in the last
Ice Age.

     *  Predictions of Einstein's Theory of Relativity have been
confirmed using laser ranging.

     *  Small-scale variations in the moon's rotation have been
measured.  They result from irregularities in the lunar gravity
field, from changes in the moon's shape due to tides raised in
the moon's solid body by the Earth and possibly from the effects
of a fluid lunar core.

     *  The combined mass of the Earth and moon has been
determined to one part in 100 million.

     *  Lunar ranging has yielded an enormous improvement in
knowledge of the moon's orbit, enough to permit accurate analyses
of solar eclipses as far back as 1400 B.C.

     The usefulness of continued improvements in range
determinations to further advance understanding of the Earth-moon
system and the need for monitoring details of the Earth's
rotation will keep the lunar reflectors in service for years to
come.

     Lunar ranging analysis at JPL is undertaken by Drs. Jean
Dickey, James G. Williams and X X Newhall and is sponsored by the
Geodynamics Branch of NASA's Office of Space Science and
Applications.   Additional analysis is accomplished at the
Harvard/Smithsonian Center for Astrophysics and the Massachusetts
Institute of Technology, both in Cambridge, Mass.; at the
University of Texas, Austin; and in France and China.

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

Date: 18 Jul 89 00:44:16 GMT
From: bfmny0![e-mail]  (Tom Neff)
Subject: Re: Apollo-11 lunar experiment still useful after 20 years (Forwarded)

In article <[e-mail]> [e-mail] (Peter E. Yee) writes:
>APOLLO-11 LUNAR EXPERIMENT STILL USEFUL AFTER 20 YEARS  ...

>     The McDonald Observatory, Ft. Davis, Texas; the Lure
>Observatory atop the extinct Haleakala volcano on the island of
                      ^^^^^^^^^^^^^^^^^^^^^^^^^
>Maui, Hawaii; and a third observatory in southern France near
>Grasse, regularly send a laser beam through an optical telescope
>and try to hit one of the reflectors.  ...

Sorry, NASA - Haleakala is not extinct!  It is dormant, having last
erupted in 1790.  That's not very long ago on an Earth scale.
Geologists keep watch to see if they can detect continued activity.
Let's hope for NASA's sake their search goes unfulfilled.  :-)

(I've been up to the Lure Observatory - it's a fantastic setting, about
10,000 ft MSL.  A near moonscape, but dotted with rare indigenous
silverswords.  Anyone vacationing in Maui should take in a Haleakala
sunrise; if you do so, the Lure domes (together with USAF tracking
station) are just a short hike up to the summit.)
--
"My God, Thiokol, when do you     \\    Tom Neff
want me to launch -- next April?"  \\    uunet!bfmny0!tneff

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

Date: 7 Jul 89 20:24:42 GMT
From: dinl![e-mail]  (kevin w. holroyd)
Subject: TF-104

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

>Greenamyer's F-104 was the structural test article--I'm not sure I'd
>like to fly in something used to test structural fatigue life!
>There's another TF-104, in a museum in Texas that also has a MiG-15
>and an F-86.  One of our test pilots flies all three for them.

All three of these airplanes participated in an air show at Centennial
last year.   One day after the show was over, I was working with a student
doing touch and goes.  I heard the Starfighter call for clearance to taxi on
ground freq.  Suitably warned, I timed our pattern so we would be on upwind
(we were on the parallel runway) when the TF-104 took off.  What a sight.
It was up and out of there and very quickly, and soon was only a smoke trail in
the distance.  And I'm sure he was throttled back since we were under
a TCA.
--
*******************************************************************************
Kevin W. Holroyd            *
CFI Aspen Flying Club            * Got tired of last .signature file
Denver CO.                *
*******************************************************************************

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

Date: Sun, 9 Jul 89 04:00:16 PDT
From: Eugene Miya <[e-mail]>
Subject: Reminders for Old Farts

Hints for old users (subtle reminders) You'll know these.

Minimize cross references, [Do you REALLY NEED to?]
Edit "Subject:" lines especially if you are taking a tangent.
Send mail instead, avoid posting follow ups. [1 mail message worth 100 posts.]
Read all available articles before posting a follow-up. [Check all references.]
Cut down attributed articles.  Summarize!
Put a return address in the body (signature) of your message (mail or
article), state institution, etc. don't assume mail works.
Use absolute dates.  Post in a timely way.  Don't post what everyone will
get on TV anyway.
Some editors and window systems do character count line wrapping:
please keep lines under 80 characters for those using ASCII terms (use <CR>).

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

Date: 12 Jul 89 22:40:04 GMT
From: frooz!cfa250![e-mail]  (Jonathan McDowell)
Subject: News of the Week (well, Month) -19


Jonathan's Space Report

Jul 12, 1989 (no. 19)

Finally I have access again, so here goes on a catchup..
---------------------------------------------------------------------

OV-102 Columbia due to be rolled out to the pad tomorrow
for mission STS-28.

The first Titan 4 launch on Jun 15 was a success. Its payload was
a new generation missile early warning satellite. The upper stage
was an IUS, the same stage used by the Shuttle to launch TDRS
and Magellan.

The last Ariane 3 went into orbit on Jul 11. It carried ESA's
Olympus experimental communications satellite, formerly known as
L-SAT. Ariane 4 will now be the standard Ariane variant.

The first Resurs-F remote sensing satellite was recovered on Jun 17
after 23 days in orbit; a second Resurs-F satellite went into
space on Jun 27. On Jul 5, another similar remote sensing satellite,
also operated by the Priroda center, was launched and given the name
Kosmos-2029; the distinction between the satellites given the new
Resurs-F name and similar satellites which are still given the
Kosmos code name is not clear yet.

Another Soviet program was further declassified with the launch on
Jul 4 of Nadezhda, a civilian navigation satellite. The Nadezhda
satellite carries Doppler-type navigation equipment and a
COSPAS-SARSAT search-and-rescue system. Satellites of this class
have been launched for over a decade with Kosmos codenames; it appears
that the various civilian subprograms are being separated from the
Kosmos program and declassified.

Two recent launches by Proton to geostationary orbit: Raduga-1 on Jun 21
and Gorizont on Jul 5.  Previous Raduga satellites have been named
simply 'Raduga' rather than 'Raduga-1', so this may imply that a
'Raduga-2' model will be introduced soon.


Kosmos-2026 launched Jun 7, a Soviet navy navigation satellite.

The 38th Molniya-3 launched Jun 8, a Soviet comms relay satellite.

Kosmos-2027 launched Jun 14, probably a radar calibration target
or some other kind of military support satellite.

Kosmos-2028 launched Jun 16, a GRU recon satellite replacing Kosmos-2018
which landed on Jun 19.


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

End of SPACE Digest V9 #556
*******************