Uranus satellites

Up to now 27 satellites of Uranus are known. The properties of Uranus satellites with a diameter > 100 km are listed in Table 4.3. 

Diacetylene (HC=C—C=CH) has been identified as a component of the hydrocarbon rich atmospheres of Uranus Neptune and Pluto It is also present m the atmospheres of Titan and Triton satellites of Saturn and Neptune respectively... 

Our solar system consists of the Sun, the planets and their moon satellites, asteroids (small planets), comets, and meteorites. The planets are generally divided into two categories Earth-like (terrestrial) planets—Mercury, Venus, Earth, and Mars and Giant planets—Jupiter, Saturn, Uranus, and Neptune. Little is known about Pluto, the most remote planet from Earth. 

Effects of condensation are also seen in the bulk compositions of the planets and their satellites. The outer planets, Uranus and Neptune, have overall densities consistent with their formation from icy and stony solids. The satellites of Uranus have typical densities of 1.3g/cm which would tend to indicate a large ice com-... 

How do giant planets form Two different models, disk instability versus core accretion followed by gas collapse, are viable. They require very different timescales, have very different implications for satellite formation and internal composition, and may have implications for the ubiquity of giant planets and terrestrial planets around other stars. The formation of Uranus and Neptune is even less well understood, and no agreement exists as to whether these are stillborn Jupiters or the product of a distinct kind of formation process. 

Due to the unique orientation of Uranus s spin axis, and therefore the satellites orbits, only the southern hemispheres of these satellites have been... 

Cmikshank D. P. (1980) Near-infrared studies of the satellites of Saturn and Uranus. Icarus 41, 246-258. 

Cruikshank D. and Brown R. H. (1986) Satellites of Uranus and Neptune, and the Pluto-Charon System. In Satellites (eds. J. A. Burns and M. S. Matthews). University of Arizona... 

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. 

Neptune s large satellite Triton, which has a very thin nitrogen atmosphere with clouds, plumes, and haze, an extremely cold surface with nitrogen, methane, carbon monoxide, and carbon dioxide ices which interact with the atmosphere, and a fairly high mean density, make it seem more like Pluto than the other satellites of Neptune and those of Saturn and Uranus. Not enough is known about Pluto to explore these similarities this probably awaits future missions to Pluto, especially the New Horizons mission that NASA hopes to launch in 2006. 

Like the case for Uranus s rings, the origin and evolution of Neptune s rings are unknown. Are they the result of earlier tidal disruption of other nearby satellites Are they a transitory phenomenon, or will they persist for millions or billions of years Comparison of the positions of the arcs in the Adams ring observed by Voyager 2 in 1989 with their positions extrapolated back in time to 1984 and 1985 shows that they match the positions of three occultations of stars observed in those years. This indicates that the arcs in the Adams ring are stable over time intervals of at least five years. 

Surface compositions of icy satellites can be observed by reflection spectroscopy (UV to near-IR 0.2-5 pm) [5J. The physical properties and surlace compositions of icy bodies are summarized in Table 9.4. Major satelhtes of Jupiter (except for lo), Saturn, and Uranus show clear evidence of H2O ice (ice I) on Oieir surfaces. Altliough physical properties, such as density, radius, albedo, and surface structure of tlrese satellites differ greatly, they share basic compositional similarity. It is thus assumed that the ice of these satellites is pure H2O when we discuss Oieir internal structiue. The large spectral differences among satellites reflect surface modification histories by impact, volcanism, tectonics, and solar radiation. It is noted that SO2, O2, and O3 are trace components and contaminants. No NH3 or CH) ices, predicted by the equilibrium condensation theory, have yet been detected on these satellites. 

Solid N2, CH4, H2O, and CO have been found on Triton and Pluto, witli additional CO2 on Triton. The molecule N2 dominates both surfaces, and other molecules are trapped in an N2 matrix. The only molecule identified on Charon is H2O. Surface compositions of these two bodies are quite different from those of satellites of Jupiter, Saturn, and Uranus. The compositional relationsliip of Triton and Pluto to that of tlie Edgeworth-Kuiper belt objects, and to tlie comets, is still unclear. 

At the time, more than a dozen planetary satellites had already been discovered for Jupiter, Saturn, Uranus, and Neptune. None had been found for Venus or Mercury, nor were they likely to be found, given the proximity of these planets to the Sun. Mars likewise had no satellites. .. or, at least, none that had yet been discovered. 

The outer planets also tend to have a number of satellites with (at last count) 56 orbiting Saturn, 63 around Jupiter, 27 around Uranus, and 13 around Neptune, compared to the virtual absence of satellites in the inner planets Mercury with 0 Venus, 0 Earth, 1 and Mars 2. 

Kuiper s list of astronomical accomplishments is impressive. In addition to his work on binary stars, the atmospheres of planets and satellites, and the formation of the solar system, he discovered the fifth moon of Uranus, Miranda, and Neptune s second moon, Nereid he was an early advocate of the use of jet airplanes for high-altitude astronomical observations and he accurately predicted the nature of the lunar surface before any human had walked on it. In recognition of these achievements, Kuiper was awarded the Janssen medal of the French astronomical society and the Order of Orange Nassau by the Dutch government. Kuiper died in Mexico City on December 24,1973, while examining a number of possible sites for a new observatory. 

Researchers have learned a vast amount of new information about Jupiter, Saturn, Uranus, Neptune, Pluto and the Kuiper Belt Objects in the last century. Improved terrestrial telescopes, the Hubble Space Telescope, and space explorations such as Voyager 1 and 2, Galileo, and Cassini have produced new data that will take astrochemists years to analyze and interpret, providing them with even more detailed information about the chemical composition of the atmospheres, satellites, surfaces, and other features of the outer planets and their associated bodies. 

Solar system Jupiter and satellites Saturn and satellites Uranus and satellites Multi stellar systems The Galaxy 1.16 1.25 1.043 1.2 from 1.15 to 7.2 about 1.2... 

These steps are represented by the index n in Table 5.4. Each value of n represents an allowed orbital distance for a satellite from its parent attractor. The planets have indices of Neptune(O), Uranus(2), Saturn(6), Jupiter(9), Asteroids(12), Mars(15), Earth(18), Venus(21) and Mercury(24). Because of the self-similar symmetry of the golden spiral this progression can be continued indefinitely on a continuously increasing scale. 

Uranus -- the second largest planet in the solar system with retrograde revolution. Uranus a gaseous planet and it has 10 dark rings and 15 satellites. 

The outer or giant planets - Jupiter. Saturn, Uranus, and Neptune - are massive low-density bodies with a rocky core surrounded by deep layers consisting mainly of solid, liquid, and gaseous hydrogen and helium. They are much further from the sun and therefore much cooler. All have large numbers of satellites Jupiter has at least 63 Saturn at least 61 Uranus 27 and Neptune 13. The outer planets also have ring systems composed of smaller bodies, rocks, dust, and ice particles. 

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