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Subject: SPACE Digest V11 #578

SPACE Digest                                     Volume 11 : Issue 578

Today's Topics:
               CASSINI MISSION PROFILE
             Anyone Know What MOL Is/Was?
           Re: Anyone Know What MOL Is/Was?
                 Re: Pegasus

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Date: 25 Jun 90 18:27:33 GMT
From: mcsun!ukc!icdoc!mvax.cc.ic.ac.uk!sund![e-mail]  (M.S.Bennett Supvs= Prof Pendry)
Subject: CASSINI MISSION PROFILE


                FACT SHEET:
                THE CASSINI MISSION


    The ringed planet Saturn, its major moon Titan andcomplex
system of at least 16 other satellites will be thedestination
for NASA's and the European Space Agency's Cassini Mission.
Named for the Italian-French astronomer who  discovered several
of Saturn's moons, Cassini is under  study at the Jet
Propulsion Laboratory as one of two  initial projects in the
Mariner Mark II series of missions  to the outer solar system.
Early during the spacecraft's four-year tourorbiting Saturn, it
will launch a parachuted probe descendingthrough Titan's dense
atmosphere to the surface of thesatellite -- which boasts
unique organic-like chemistry thatcould provide clues to the
origin of life on Earth.  On its way to Saturn, Cassini will
also execute anencounter with an asteroid and will fly down the
magnetotailof Jupiter, performing studies complementing NASA's
Comet Rendezvous Asteroid Flyby (CREJmission and the
Galileomission to Jupiter.  Recommended by NASA's Solar System
Exploration Committee in its report to the space agency in the
early 1980s, the Mariner Mark II series will use shared
design concepts and advanced manufacturing techniques to build
a number of unmanned spacecraft to explore the solar
system beyond the orbit of Mars. CRAF and Cassini are the first
two missions proposed in the series.
                MISSION OVERVIEW

    As currently planned, Cassini would be launched in April 1996
on an expendable rocket. NASA would provide the Titan-Centaur
launch vehicle and the Cassini orbiter spacecraft; the European
Space Agency (ESA) would contribute the Titan probe. NASA and
ESA member countries would providescience instruments for both
the orbiter and probe.  In order to reach Saturn, Cassini will
first execute flybys of the Earth and of Jupiter in order to
gain "gravity assist" boosts in velocity to send it on its way.
The first flyby of Earth will take place 26 months afterlaunch,
followed by the Jupiter flyby some 19 months later. Cassini
would then arrive at Saturn in October 2002.  During the first
leg of its trip -- after launchand before its first Earth flyby
-- Cassini will navigatethrough part of the asteroid belt and
could perform anencounter with the asteroid Maja in March 1997.
After flyingby the Earth at a distance of 300 kilometers (about
190 miles), the spacecraft will be flung out through the
asteroid belt where it may be possible to encounter another
asteroid.  Maja is a carbonaceous, or "C" type, asteroid
78k ilometers (about 50 miles) in diameter. Two small
asteroids are being considered as possible additional targets
(only one of the two asteroids could be visited).  Cassini's
final encounter before proceeding toSaturn will be with
Jupiter, which it will pass at a distanceof about 3.6 million
kilometers (about 2.2 million miles),some 50 times the radius
of Jupiter itself. Cassini's flightpath will take it for 130
days down through a region that nozt9aft has explored more than
briefly -- the giantplanet's magnetotail, a long tube of
Jupiter's energy fieldtrailing many millions of miles away from
the Sun.  Upon reaching Saturn the spacecraft will swingwithin
1.8 Saturn radii of the planet to begin the first ofsome three
dozen highly elliptical orbits during theremainder of its
mission. Eighty-five days after reachingSaturn -- traveling
back in toward the planet as it completesits first orbit --
Cassini will release its instrumentedprobe to begin descent to
Titan.  Eleven days later the probe will enter Titan'sdense
atmosphere, buffered at first by a heat shield.Throwing off
that protection, the probe will then deploy itsparachute for
final descent to the surface.  After relaying to Earth data
up linked from theTitan probe, Cassini will continue with orbits
of Saturn andflybys of most of the planet's 16 or more other
moons. Planscall for 40 targeted flybys including 36 close
encounters ofTitan, two of the major moon Iapetus, and one each
of Enceladus and Dione. Cassini will make 26 non-targeted
flybysof the Saturnian moons. In addition, the spacecraft's
orbits will allow it to study Saturn's polar regions after
examining the planet's equatorial zone.

        SATURN AND ITS MOONS: UNRESOLVED QUESTIONS

    Much has been learned about the ringed planet sinceRenaissance
astronomers first turned their telescopes on itin the 17th
century. Many questions remain, however, whichcould provide
clues to how the solar system evolved and howlife began on
Earth.  One of the bright planets known to the ancients,Saturn
was first studied via telescope by Galileo Galilei (1564-1642)
and, in the generation following him, by suchEuropean
astronomers as the mission's namesake, Cassini. Glimpsing the
planet's famous rings through an earlytelescope, Galileo first
thought them to be two smallerplanet-like bodies flanking the
main planet Saturn; onlyobservations by others with later,
better telescopes revealed their true nature.  The greatest
wealth of information on the planethas come from unmanned
spacecraft. Initially reconnoitered by NASA's Pioneer 11, the
planet was encountered by Voyager 1and Voyager 2 during flybys
in 1980 and 1981, respectively.  Those missions showed Saturn
to be a giant gaseous globe of hydrogen and helium 95 times
more massive than the Earth, buffeted by winds of up to 500
meters per second(1,100 miles per hour). The ring system proved
to be muchmore complex than previously realized, with intricate
"braiding" in some parts of the system. Small moons were
also discovered by the spacecraft, bringing the total of
Saturnian moons to at least 17.  Because of the brief nature of
those flybys, manyquestions remain for Cassini to explore. In
studying Saturn's magnetosphere -- the pocket of energy
enveloping the planet,much like Earth's radiation belts --
scientists hope tounderstand the configuration and dynamics of
the magnetosphere; the nature, source and fate of its
energy particles; how it interacts with the solar wind,
satellites and rings; and how Titan interacts with the solar
wind and Saturnian magnetosphere.  At the planet itself, topics
of study includecloud properties and composition of the
atmosphere; winds andtemperatures; Saturn's internal structure
and rotation; theplanet's ionosphere; and Saturn's origin and
evolution.Science objectives in respect to Saturn's rings
include studies of their structure and composition, dynamic
processes, interrelations of the rings and Saturniansatellites,
and the dust/micrometeoroid environment at therings.  Because
of the dense atmosphere shrouding the moonTitan, little is
known of its surface -- whether it is solidor covered with
liquid oceans. At Titan, scientists hope togain a better
understanding of abundances of elements andcompounds in its
atmosphere; distribution of trace gases andaerosols; winds and
temperatures; surface state andcomposition; and the satellite's
upper atmosphere.  Saturn's other major moons are ice-covered
bodies. Scientists wish to use Cassini to study their
characteristicsand geological histories; how their surfaces are
modified over time; composition and distribution of materials on
their surfaces; overall composition and internal structure of
the satellites; and how they interact with
Saturn's magnetosphere.  To carry out those studies, the Cassini
orbiter will carry 15 science experiments, with nine more on the
Titan probe.  The orbiter will house several instruments on
its directable, high-precision scan platform: a
solid-stateimaging system; ultraviolet spectrometer;
near-infrared spectrometer; mid-far-infrared spectrometer; a
micro wave radiometer/spectrometer; and a high-speed photometer.
Instruments on the orbiter's turntable platformare: a dust
analyzer; energetic gas/hot plasma detector; aplasma/radio-wave
spectrometer; and a plasma spectrometer.  Located on a separate
orbiter aeronomy platformwill be a neutral/ion mass
spectrometer and an ionanalyzer/Langmuir probe. A magnetometer
will be mounted on aseparate boom. The orbiter's high-gain
antenna will also beused for radar to map Titan through the
satellite'satmospheric veil. The spacecraft's radio system will
also beused for radio science experiments.  The Titan probe's
experiments include an imager/spectrometer to relay photos as
the probe descends; a radaraltimeter; doppler tracking; a
lightning/radio detector; alaser spectrometer/particle size
counter; a gas chromato-graph/mass spectrometer; an aerosol
collector/pyrolyzer; anatmospheric structure instrument; and a
surface sciencepackage.

        THE ASTRONOMER IN HISTORY

    Gian Domenico Cassini -- or, in his adopted  country,
Jean-Dominique Cassini -- was born in Perinaldo,  Italy, in
1625 and later settled in Paris.  Before his  death in 1712,
Cassini became renowned for diverse work inastronomy, including
the discovery of four of Saturn's  major moons and a dark,
narrow gap ("Cassini's Division")splitting the planet's rings.
Interested in mathematics and astronomy as a youth,Cassini in
his early 20s was invited by a rich marquis andamateur
astronomer to work at the nobleman's observatory nearBologna,
Italy. At the age of 25 he was named to theprincipal chair of
astronomy at the University of Bologna.  Alternating astronomy
with hydrology studiessolving problems of river flooding for
the pope, Cassinibegan developing theories of planetary motion,
observing comets and mapping solar eclipses.  Through
friendships with lensmakers, Cassini was able to obtain very
powerful telescopes; by the time he was 40 he began
observations of planets which cemented his fame.He studied the
rotation rates of Jupiter and Mars, coming upwith periods very
close to those currently accepted.
     When he was 43, Cassini published a table of movements of the
moons of Jupiter, which was used by astronomers and navigators
for many years on expeditionsaround the world. By observing
eclipses of Jupiter's moons from two distant sites, explorers
could develop accurate longitudes of various points around the
Earth.  In 1669 Cassini accepted a generous offer to
leave Italy and join the new Academie Royale des Sciences in
Paris;four years later he became a French citizen, and when he was 49
he married the daughter of a French lieutenant general.

    Using new telescopes, Cassini made his most celebrated
discoveries related to Saturn from 1671 to 1675. The planet's
largest moon, Titan, had been discovered some 20 years previously by
the Dutch scientist Christiaan Huygens. Cassini discovered Saturn's
four other large moons, Iapetus,Rhea, Tethys and Dione. He also noticed
changes in the brightness of Iapetus; to explain it, Cassini developed
a theory that the satellite always turned the same face toward its
parent planet.

    In 1675 Cassini discovered that Saturn's rings are split into
two parts by a narrow division, which becamenamed for him in
the language of astronomy used today. Healso put forth the notion,
since proven, that the rings arenot solid but rather are made up of
huge numbers of small particles.

    Cassini's heirs were also influential in  French astronomy.
They included his son, Cassini II (Jacques Cassini,
1677-1756); grandson Cassini III (Cesar-FrancoisCassini de Thury,
1714-1784); and great-grandson Cassini IV(Jean-Dominique Cassini,
1748-1845).


                 ___________


At JPL, Ronald F. Draper is Mariner Mark II projectmanager. Charles
Kohlhase is Cassini science and mission design manager. Linda Horn is
Cassini deputy study scientist.Cassini is managed by JPL for NASA's
Office of Space Scienceand Applications.
                ##### 8-4-88 FOD@
/------    -------    -----\       /------   |  ======================  |
|          |          |      \    |          |  M. Sean Bennett         |
\-----\    |----      |       |    \-----\   |  UKSEDS TECH.OFF.        |
       |   |          |      /            |  |  Janet:[e-mail]  |
------/    -------    -----/       ------/   |  Bitnet-                 |
                                             |  SEDS%CC.IC.AC.UK@ukacrl |
                                             |  ======================  |

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Date: 26 Jun 90 03:19:28 GMT
From: cs.utexas.edu!uwm.edu!srcsip!jhereg!wd0gol!newave![e-mail]  (John A. Weeks III)
Subject: Anyone Know What MOL Is/Was?

While looking at the space suit exhibits at the Kansas
State Cosmoshere recently, I saw a space suit from the
"MOL" project.  Although I have looked through all of
my space books, I have been unable to find out anything
about MOL except the following:

  1. It stands for Manned Orbiting Labratory
  2. It was a super-secret Air Force project
  3. It was cancelled in 1968

Can anyone tell me more about MOL, or at least point
me to some references?  Specifically, I am curious as to
what the mission was, what if any hardware was built,
and why it was cancelled.

-john-

--
===============================================================================
John A. Weeks III               [phone]               [e-mail]
NeWave Communications                ...uunet!rosevax!bungia!wd0gol!newave!john
===============================================================================

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

Date: 26 Jun 90 18:26:45 GMT
From: mephisto!prism![e-mail]  (Matthew Thomas DeLuca)
Subject: Re: Anyone Know What MOL Is/Was?

In article <[e-mail]> [e-mail] (Daniel McGurl) writes:
>In article <[e-mail]> [e-mail] (Matthew DeLuca) writes:
>>As to the mission, a hint can be gotten from the fact that the 'missing'
>>KH-10 designation in the series of U.S. recon platforms was taken by the
>>MOL.  William Burrow's book _Deep Black_ mentions the MOL a little, but
>>does not go into great detail.  I highly recommend the book, though, if you
>>are interested in U.S. aerial and space reconaissance...it's the best
>>book on the topic I've seen.
>
>Well, that's not quite correct.  First of all, the KH-10 project was scrapped
>mainly because it became obsolete before actually getting of the drawing
>board.  The KH-10 had been given the designation but no hardware was ever
>built for it (Well, that we know about anyway :-)...

I have since run home (living a block from campus has its benefits. :) to
retrieve _Deep Black_.  On page 235, the author states 'There was a
satellite assigned the Keyhole number 10, though it was never built
because the KH-11 made it obsolete.  The MOL was the KH-10.'  So yes,
the KH-10 was rendered obsolete, but it was indeed the MOL.

Now that I have the book in front of me, I find that it covers the MOL
in a little more depth than I recalled.  Quoting without permission:

'[The KH-9] was a partial substiute for another of the extremely ambitious
programs conceptualized by the Air Force in the 1960's.  This one was
called the Manned Orbiting Laboratory, or MOL, and it was supposed to be
able to accomplish a formidable variety of tasks, including inspecting
satellites in space, testing the accuracy of an orbital bombardment
system, commanding and controlling military operations during all-out
war, testing the effects of month-long missions on astronauts, and
performing both imaging and ELINT [ELectronic INTelligence -mtd]
reconaissance.

The MOL, a cylinder having about thirty-four cubic yards of work space,
was to be lifted into orbit by a thrust-augmented Titan 3C.  Once in low
orbit, it was to be joined by two astronauts in a Gemini capsule who
would dock, climb inside, and perform the various experiments in
addition to operating the reconaissance apparatus.  They were then to
return to earth in their capsule, leaving the laboratory to await a
replacement crew.'

>Actually, I seem to recall that the plans for the MOL have been changed to
>become an unmanned recon platform.  I think in the long run that there was
>no real benedit from having people on board.  True, they could fix point
>failures, but if the platforms work well, then a service mission every once
>in a while would fix it.  I beleive there were also some concerns that people
>in a recon platform might be considered spies in times of conflict.

This is correct.  In addition to the cost overruns (the project had
consumed $1.6 billion by the time it was cancelled, in 1969), the CIA
was concerned that the Soviets would use asat weaponry to attack the
MOL, on the same premise as using SAM's to shoot down Gary Power's
U-2 in 1960.  At any rate, the other, unmanned, satellites in the
Keyhole series were performing the recon job admirably...it was decided that
the benefit of having men on board was not worth the extra cost
involved.

--
Matthew DeLuca
Georgia Institute of Technology      Do not meddle in the affairs of wizards,
Office of Computing Services         for they are subtle, and quick to anger.
ARPA: [e-mail]

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

Date: 26 Jun 90 20:50:19 GMT
From: orc!inews!td2cad!yoyodyne![e-mail]  (john reece)
Subject: Re: Pegasus

In article <[e-mail]>, [e-mail] (Henry
Spencer) writes:
> In article <[e-mail]>
[e-mail] writes:
> >...launching Pegasus from an XB-70 instead of a B-52.
> >        My question is: why not launch from an old B-58? ...
>
> Because the extra speed and altitude are not that much help, and flying
> and maintaining a (now) one-of-a-kind high-performance aircraft would be
> very expensive.

How about using a C-5, or C-17, and building a bigger rocket with a larger
payload?  Either one can carry twice the payload of a B-52, though
I'm not sure about their speeds or ceilings under load.



John Reece
Not an Intel spokesman
[e-mail]

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End of SPACE Digest V11 #578
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