Jupiter internal structure

The density estimates in Table 7.1 show a distinction between the structures of the planets, with Mercury, Venus, Earth and Mars all having mean densities consistent with a rocky internal structure. The Earth-like nature of their composition, orbital periods and distance from the Sun enable these to be classified as the terrestrial planets. Jupiter, Saturn and Uranus have very low densities and are simple gas giants, perhaps with a very small rocky core. Neptune and Pluto clearly contain more dense materials, perhaps a mixture of gas, rock and ice. 

What are the detailed internal structures of the giant planets and how are the magnetic fields generated While the separation of helium from hydrogen seems to be assured for Saturn, it is unclear to what extent this occurs in Jupiter. Further, the distribution of elements heavier than hydrogen and helium remains unclear in Jupiter and Saturn, in part because of equation-of-state uncertainties. The interiors of Uranus and Nepmne are even less certain. For these reasons, and because of uncertainties in dynamo theory, the specific details of the magnetic field... 

Surface compositions of icy satellites can be observed by reflection spectroscopy (UV to near-IR 0.2-5 jim) [5]. The physical properties and surface compositions of icy bodies are summarized in Table 9.4. Major satellites of Jupiter (except for Io), Saturn, and Uranus show clear evidence of H20 ice (ice I) on their surfaces. Although physical properties, such as density, radius, albedo, and surface structure of these satellites differ greatly, they share basic compositional similarity. It is thus assumed that the ice of these satellites is pure H20 when we discuss their internal structure. The large spectral differences among satellites reflect surface modification histories by impact, volcanism, tectonics, and solar radiation. It is noted that S02, 02, and 03 are trace components and contaminants. No NH3 or CH4 ices, predicted by the equilibrium condensation theory, have yet been detected on these satellites. 

A cutaway representation of the internal structure of Jupiter Earth is shown at the lower right on the same scale. The core consists of solid rock (grey), ice (white) and liquid, metallic hydrogen (blue). Mark GarlickjScience Photo Library... 

Smoluchowski, R. (1967). Internal structure and energy emission of Jupiter. Nature, 215, 691-5. 

Fig. 3.15 Internal structure of Jupiter. In the upper layers the atmosphere changes to a liquid state above a thick layer of metallic hydrogen. In the center there may be a solid core of heavier elements. Credit NASA,...

Neptune is the eighth planet from the Sun and about four times the size of Earth. Astronomers consider Neptune to form with Uranus a subgroup of the Jovian planets (Jupiter, Saturn, Uranus, and Neptune). Neptune and Uranus are similar in size, mass, periods of their rotation, the overall features of their magnetic fields, and ring systems. However they differ in the structure of their atmospheres (perhaps the more conspicuous features of Neptune s clouds are caused by its significant internal energy source, which Uranus lacks), the orientations of their rotation axes, and in their satellite systems. 

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