CASSINI-HUYGENS MISSION OBJECTIVES
==================================

The Cassini-Huygens mission will accomplish a variety of scientific
objectives en route to and at Saturn [JPL D-5564].

While en route to Saturn, Cassini performed three sets of Gravitational
Wave Experiments (GWEs), each scheduled near opposition and each lasting
approximately 40 days. During these observations, Cassini acted as a point
mass which would be perturbed by propagating gravitational waves resulting
from sudden destruction (or creation) of large masses in the general
direction of the spacecraft-to-Earth line.

While en route to Saturn, Cassini was also used in two Solar Conjunction
Experiments (SCEs), each lasting approximately 30 days. The objectives of
these observations was to test general relativity and to improve our
understanding of the solar corona.

The general scientific objectives of the Cassini mission at Saturn were to
investigate the physical, chemical, and temporal characteristics of Titan
and of Saturn, its atmosphere, rings, icy satellites, and magnetosphere.
These are listed more specifically below:

Saturn (Planet) Objectives.
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a) Determine temperature field, cloud properties, and composition of the
atmosphere of Saturn.

b) Measure the global wind field, including wave and eddy components;
observe synoptic cloud features and processes.

c) Infer the internal structure and rotation of the deep atmosphere.

d) Study the diurnal variations and magnetic control of the ionosphere of
Saturn.

e) Provide observational constraints (gas composition, isotope ratios, and
heat flux, etc.) on scenarios for the formation and the evolution of Saturn.

f) Investigate the sources and the morphology of Saturn lightning, Saturn
Electrostatic Discharges (SED), and whistlers.


Titan Objectives.
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a) Determine abundance of atmospheric constituents (including any noble
gases), establish isotope ratios for abundant elements, constrain scenarios
of formation and evolution of Titan and its atmosphere.

b) Observe vertical and horizontal distributions of trace gases, search for
more complex organic molecules, investigate energy sources for atmospheric
chemistry, and model the photochemistry of the stratosphere, study
formation and composition of aerosols.

c) Measure winds and global temperatures; investigate cloud physics,
general circulation, and seasonal effects in Titan's atmosphere; search for
lightning discharges.

d) Determine the physical state, topography, and composition of the
surface; infer the internal structure of the satellite.

e) Investigate the upper atmosphere, its ionization, and its role as a
source of neutral and ionized material for magnetosphere of Saturn.


Ring Objectives.
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a) Study configuration of the rings and dynamical processes (gravitational,
viscous, erosional, and electromagnetic) responsible for ring structure.

b) Map composition and size distribution of ring material.

c) Investigate interrelation of rings and satellites, including embedded
satellites.

d) Determine dust and meteoroid distribution in the vicinity of the rings.

e) Study interactions between the rings and Saturn's magnetosphere,
ionosphere, and atmosphere.


Icy Satellite Objectives.
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a) Determine the general characteristics and geological histories of the
satellites.

b) Define the mechanisms of crustal and surface modifications, both
external and internal.

c) Investigate the compositions and distributions of surface materials,
particularly dark, organic rich materials and low melting point condensed
volatiles.

d) Constrain models of the satellites' bulk compositions and internal
structures.

e) Investigate interactions with the magnetosphere and ring systems and
possible gas injections into the magnetosphere.


Magnetosphere Objectives
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a) Determine the configuration of the nearly axially symmetric magnetic
field and its relation to the modulation of Saturn Kilometric Radiation
(SKR).

b) Determine current systems, composition, sources, and sinks of
magnetosphere charged particles.

c) Investigate wave-particle interactions and dynamics of the dayside
magnetosphere and the magnetotail of Saturn and their interactions with the
solar wind, the satellites, and the rings.

d) Study the effect of Titan's interaction with the solar wind and
magnetospheric plasma.

e) Investigate interactions of Titan's atmosphere and exosphere with the
surrounding plasma.