Major planets

Trafton has shown in 1964 that the opacity in the far infrared of the atmospheres of the outer planets is due to the rototranslational band of H2-H2 and H2-He pairs [393], It is now clear that collision-induced absorption plays a major role in the thermal balance and atmospheric structure of the major planets. The Voyager emission spectra of Jupiter and Saturn show dark fringes in the vicinity of the So(0) and So(l) lines of H2, Fig. 7.3, which are due to collision-induced absorption in the upper,... 

L. Trafton, Observational studies of collision-induced absorption in the atmospheres of the major planets. In J. Szudy, ed., Spectral Line Shapes 5, p. 755, Ossolineum, Warsaw, 1989. 

For these reasons, it is generally felt that the interstellar molecules played at most a minor role in the origin of life. However, the presence of so many molecules of prebiotic importance in interstellar space, combined with the fact that their synthesis must differ from that on the primitive earth where the conditions were very different, indicates that some molecules are particularly easily synthesized when radicals and ions recombine. Another way of saying this is that there appears to be a universal organic chemistry, which shows up in interstellar space, in the atmospheres of the major planets, and in the reducing atmosphere of the primitive earth. 

Hydrogen gas has been found occluded in meteorites, and also is present in nebulae, fixed stars, and in the Sun. Anders and Grevesse calculated mass fractions of H, He, and heavier elements (Li-U) in the solar system, and derived values of 70.683, 27.431, and 1.886%, respectively. The major planets (Jupiter, Neptune, Saturn, and Uranus) contain large amounts of hydrogen in their atmospheres, along with He, CH4, and NH3. 

The major planets are grouped small volatile-poor planets lie close to the Sun, with large volatile-rich planets further out. The main asteroid belt (2-4 AU from the Sun) is substantially depleted in mass with respect to other regions. 

Neptune is in a nearly circular orbit around the Sun at a 30.1 astronomical unit (a.u.) mean distance (4,500,000,000 km) from it, making it the most distant known Jovian planet (and probably the most distant known major planet, since recent findings indicate that the Pluto-Charon system is too small to be considered a major planet) from the Sun. Kepler s third law gives 165 years for Neptune s period of revolution around the Sun. Therefore, Neptune will not have made one complete revolution around the Sun since its discovery until 2011. 

The exact path and position of an object in space can be determined by taking into account seven orbital elements. These elements deal with the mathematical relationships between the two bodies. To determine the orbit of a celestial body, it must be observed and precise measurements taken at least three times. However, at least 20 precise observations, covering at least one full revolution, are needed for accurate orbital elements to be determined. If two bodies that move in elliptical orbits around their common center of mass (for example, the Sun and Jupiter) were alone in an otherwise empty universe, we would expect that their orbits would remain constant. However, the solar system consists of the Sun, eight major planets, and an enormous number of much smaller bodies all orbiting around the solar system s center of mass. The masses of these objects all influence the orbits of each other in small and large ways. 

Today, astronomers use high-speed computers to figure orbits in multiple body systems such as the solar system. The computers can be programmed to make allowances for the important perturbations on all the orbits of the member bodies. Such calculations have now been made for the Sun and the major planets over time intervals of up to several tens of millions of years. 

There are many symbols of Alchemy and almost all have different meanings. One in particular which is useful is Dee s Hieroglyphic Monad. Some ascribe this symbol to the elusive spirit Mercurius—the Alpha Et Omega of Alchemy. Depending on the system one uses there are many steps in Alchemy most are related back to the planets and zodiac. The Monad, for example, is representative of the seven major planets (of old) which relate to the seven stage system. 

The general three-body problem Three bodies with finite masses moving under their gravitational attraction. This is a model for a triple stellar system. In many astronomical applications one of the three bodies has a large mass and the other two bodies have small, but not negligible masses. This is a model for an extrasolar planetary system, or a system of two satellites moving around a major planet. In the latter two cases the two small bodies move in perturbed Keplerian orbits. 

We shall apply the above described theory to the motion of a small body (asteroid, Kuiper belt object, satellite) moving around the Sun in a nearly Keplerian, elliptic, orbit, and perturbed by a major planet. 

We perturb now the above two-body problem by adding to the model the gravitational attraction from a major planet (for example Jupiter), which we assume that revolves around the Sun in a circular orbit with constant angular velocity n. The study of the periodic orbits will be made in the rotating frame that rotates with constant angular velocity n. The new Hamiltonian has the form... 

The last four entries in the table are dwarf planets as defined by the International Astronomical Union. These are bodies in orbit around the sun that are massive enough to adopt a near-spherical shape as a result of their self-gravity, but are appreciably smaller than the major planets. Plutoids form a subset of the dwarf plan-... 

The distance between Earth and Sun is obtained by measuring the parallax of another planet and use of Kepler s third law for the orbital periods of the planets. The closer an object is to the observer, the larger its parallax. On occasion the minor planet Eros approaches the earth more closely than any of the major planets and measurement of its parallax displacement during diurnal rotation of the earth at such time provides one of the best estimates of the AU. 

A similar trend is found in each of the planetary systems. The major moons with N > 1 carry most of the angular momentum, with one or two dominating. Like the asteroid belt and the inner planets around the sun, the major planets have a large number of insignificant moons and rings with N < T. As in the solar system with the Kuiper belt beyond the orbit of Neptune, lesser moons on remote irregular orbits are associated with the four major planets. 

Any body in our solar system that has a surrounding neutral gas envelope, due either to gravitational attraction (e.g., planets) or some other processes such as sputtering (e.g., Europa) or sublimation (comets), also has an ionosphere. The very basic processes of ionization, chemical transformation, and diffusive as well as convective transport are analogous in all ionospheres the major differences are the result of the background neutral gas compositions, the nature or lack of a magnetic field, and the differences in some of the important processes (e.g., photo versus impact ionization). The remainder of this chapter describes the characteristics of the Venus ionosphere as a representative example of the so-called inner or terrestrial planets, the ionosphere of Jupiter as representative of the outer or major planets, and finally the ionosphere of Titan to represent one of the moons in our solar system. 

The surfaces of the satellites of the major planets are of interest both in themselves and because they provide constraints on theories for the contraction history of the central body. 

The mean orbits of all planets, including Ceres, the largest asteroid, are correctly predicted [13] by the relative distances from the spiral center. With the orbital radii expressed as rational fractions, a quantized distribution of major planets, as numbered, is revealed. On this scale the orbit of Ceres measures r and those of the inner planets are rational fractions of the golden ratio. The same pattern was shown to repeat itself for the orbital motion of planetary moons and rings. 

The self-similarity between atoms and planetary systems goes even further. Whereas an atomic nucleus is surrounded by an electronic core and a valence shell, the solar system has an inner core of rocky planets with major planets beyond the asteroid belt. A major planet like Saturn has a core of rings and minor shepherding moons, surrounded by regularly spaced major moons. In the case of the solar system, all planets have characteristic quanmm numbers that converge from both ends to the golden ratio at the chaotic asteroid belt. The boundary between planetary rings and major moons is likewise defined by r. 

Long before spacecraft encounters, celestial mechanics had been employed to determine the masses of those planets that possess moons. With the exceptions of Mercury and Venus, for which the arguments were more indirect, the masses of all the planets are now known from satellite observations. Detailed examination of the periodicities of their moons also reveals that they interact through resonant orbits, which causes the structuring of the radial distribution of the planetary satellite systems. Detailed observations of satellite motion also permit the determination of internal mass distribution and oblateness for most of the planets. These determinations have been augmented for the outer planets by direct flybys with the Voyager 1 and 2 spacecraft. Finally, mutual phenomena of the moons of several of the major planets provide the determination of satellite masses through the solution of the motion under mutual perturbations for the satellite systems. 

The Voyager spacecraft detected a variety of low-frequency radio emissions from Neptune during its encounter in 1989. The emissions were similar to those observed from the other major planets. 

Absorption and emission features can also appear in surface spectra. The two principal causes are emissivity differences and vertical temperature gradients in the material just beneath the surface. As a rule, water ice and minerals such as silicates are very opaque in the thermal infrared. Optical depth unity is located at levels too close to the surface to span a noticeable vertical variation in temperature. As a result, features in the spectra of the icy satellites of the major planets, and of the surfaces of such bodies as the Moon, Mars, and Mercury, ate expected to arise almost solely from variations of emissivity with wavenumber. 

According to Figs. 8.2.2 and 9.1.1, a greenhouse effect appears to exist for all planets with substantial atmospheres, although in the cases of Jupiter, Saturn, and Neptune the effect is overwhelmed at very large depths by an internal heat source. This heat source leads to dynamically active lower tropospheres in these major planets, a subject discussed in the next section. 

In spite of this dense aerosol, enough near infrared radiation penetrates Titan s atmosphere to heat the surface slightly and create a small greenhouse effect. The principal source of thermal infrared opacity is collision-induced absorption due to N2-CH4-H2 combinations. There is a fairly transparent window between 400 and 600 cm however, due to the small amovmt of hydrogen in Titan s atmosphere, and this severely limits the magnitude of the effect. The atmospheres of the major planets do not suffer from the same difficulty, since they are composed principally of hydrogen, and the window between 400 and 600 cm is effectively closed. 

In China, the five major planets that were known by ancients are associated with and named after the elements Venus is gold, Jupiter is wood. Mercury is Water, Mars is Fire, and Saturn is Earth. Additionally, the Moon represents Yin, and the Sun represents Yang. 

The motion of meteoroids can be severely perturbed by the gravitational fields of major planets. Jupiter s gravitational influence is capable of reshaping an asteroid s orbit Ifom the main belt so that it dives into the inner solar system and crosses the orbit of Earth. This is apparently the case of the Apollo and Vesta asteroid fl agments. 

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