Part 1 of Essay
orbits the Sun at a mean distance of 1.427 billion km with a period of 29.4577 tropical years. The orbit is inclined 2.49 degrees to the ecliptic, or Earth orbital, plane and has an eccentricity of 0.0556. At 's distance from the Sun, it receives only 0.01 of the unit solar radiation flux that the Earth does. Among planet ....

Part 2 of Essay
.... size, low density, and corresponding extensive atmospheres. Current models of the interior indicate that below the relatively thin opaque cloud layer is an extensive, clear hydrogen-helium atmosphere. Data on the internal heat flux, the detailed gravity field, and the observed upper-atmosphere hydrogen-helium ratio satisfy a model of the interior where the ratio of hydrogen to helium decreases with depth. The gas density gradually increases downward and the gas transforms into a liquid. Further down the pressure ....