**3. Background: science goals and Cassini's design**

The science objectives of the prime Cassini mission were to determine:

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• Radar

• Radio Science (RS)

*Robotic Autonomous Spacecraft Missions: Cassini Mission-To-Saturn Example*

• The elemental, molecular, isotopic, and mineralogical compositions of Saturn,

• The physical, morphological, and geological nature of the above objects

• The physical and chemical processes within the atmospheres of Saturn and

• The physical and chemical processes taking place on the surfaces of the rings

• The composition and mapping of Saturn's magnetosphere and planet/ring

• The composition and mass distribution of ice and dust grains within the

• Map the surfaces of Titan and the icy satellites at wavelengths from extreme

In order to achieve these science goals, several instruments were implemented

Huygens spacecraft consisted of 18 scientific instruments. Twelve instruments were placed on the Cassini orbiter (see **Figure 6**), and six were contained within the

• Measure plasma waves and radio emissions in the Saturnian system

onto the Cassini orbiter and Huygens probe vehicles. The combined Cassini-

*DOI: http://dx.doi.org/10.5772/intechopen.82161*

Titan (including the dynamics)

Saturnian system

ultraviolet to Ku-band radar

• Search for gravitational waves

Huygens probe instruments (see **Figure 7**). Orbiter remote sensing instruments:

• Imaging Science Subsystem (ISS)

• Composite Infrared Spectrometer (CIRS)

• Ultra-Violet Imaging Spectrograph (UVIS)

Orbiter fields, particles, and waves instruments:

• Dual Technique Magnetometer (MAG)

• Radio and Plasma Wave Science (RPWS)

And to:

and moons of the Saturnian system

Titan, the smaller moons, and Saturn's rings

• The physical and dynamic properties of the rings

• Examine the possibility of exobiology on Titan

• Visible and Infrared Mapping Spectrometer (VIMS)

interactions; interactions with the moons and solar wind


And to:

*Aerospace Engineering*

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**Figure 5.**

**Figure 4.**

A second mission extension was also granted, called the Solstice Mission (2010–2017) for a further 7 years of study (**Figures 2** and **3**). The Cassini mission ended with a final 42 orbit rotation through the outer and inner portion of the main ring system (F-Ring & D-Ring), followed by a fiery plunge into Saturn on

The science objectives of the prime Cassini mission were to determine:

September 15, 2017 (**Figures 4** and **5**, [2]).

*Cassini's proximal orbit phase & final plunge (credit: NASA/JPL).*

*Saturn's ring structure and moon system (credit: NASA/JPL/Caltech).*

**3. Background: science goals and Cassini's design**


In order to achieve these science goals, several instruments were implemented onto the Cassini orbiter and Huygens probe vehicles. The combined Cassini-Huygens spacecraft consisted of 18 scientific instruments. Twelve instruments were placed on the Cassini orbiter (see **Figure 6**), and six were contained within the Huygens probe instruments (see **Figure 7**).

Orbiter remote sensing instruments:


Orbiter fields, particles, and waves instruments:


Huygens probe instruments:


The instruments on the Cassini orbiter were body-mounted (no scanning platforms), which required the spacecraft to be oriented toward specific science targets for some instruments. Optical instruments provided imagery and spectrometry, while the Radar supplied imaging, altimetry, and radiometry. Radio links contributed information about intervening material and gravity fields. Other instruments on the orbiter were used to measure electromagnetic fields and the properties of plasma, energetic particles, and dust particles.

The Huygens probe was spin-stabilized, returning data via an S-band link to the Cassini orbiter. The probe's six instruments included several sensors to determine the atmospheric properties and composition of Titan. The probe's radiometric and optical sensors produced data on thermal balance and captured images of Titan's atmosphere and its surface. Wind profiles were captured by Doppler measurements between the probe and orbiter. Surface sensors on the probe were implemented to measure the surface impact acceleration, in addition to thermal and electrical properties.

The combined Cassini-Huygens instrument suite enabled scientists to determine the composition, physical, morphological, geological nature, and chemical processes of Saturn and Titan's atmospheres, to investigate their surfaces, and the magnetosphere of the Saturnian system.
