Saturn is one of the fascinating planets in our solar system. It is the sixth planet from the Sun situated between Jupiter and Uranus. The positioning of this captivating planet is at about 840 million miles from the Sun, compared to our planet that is about nine times less this distance. Saturn is the most prominent due to its astonishing array of rings around it. Locating it up in the sky is very easy since it is one of the brilliant lights in the sky. Its pale green color enables it to stand out from the rest of the objects in the solar system. It is the second largest planet after Jupiter. It has the highest number of moons in the solar system: eighteen. Man has attempted to investigate the mystery of this planet by carrying out three voyages, currently one is in progress (Hamilton). In September 1979, The Pioneer II journeyed to Saturn, about a year later The Voyager mission occurred, and in October 1997, the Cassini Probe started its journey. Numerous features of this planet make it one of the most astounding in our solar system.
Saturn’s diameter measures about 72 thousand miles, which is about ten times greater than the size of our planet. Despite of its huge size, it weighs much less. It is a planet filled with gas. It can float on water! Hydrogen and helium gases are the main components of the planet and it is less dense. Its lightweight coupled with its fast rotation makes it to stretch, or oblate against its center. The planet lacks a solid surface due to its gas-filled atmosphere. Spaceships are incapable of landing on this kind of surface. The clouds that is visible when observing this planet forms the top component of a very deep layer of liquid hydrogen. Steady winds propel the clouds and attain velocities of approximately one thousand miles per hour.
The systems of rings of Saturn are categorized into five main constituents: “the G, F, A, B, and C rings” (Henbest and Marten 34). In reality, the divisions of these main components are into thousands of independent ringlets. The visibility of F and G rings is impaired since they are not wide enough, while the presence of extensive thickness enables the rest to be clearly visible. Speculation has it that the rings are as old as Saturn itself is. This has led to the development of two major theories to explain the formation of these rings. Edouard Roche proposed in the 19th century that the rings were originally a moon of the planet whose orbit underwent deterioration up to the point that it approached a convenient distance that the tidal forces were able to shred it. A slight deviation from this school of thought suggests that the moon fell to pieces after having a collision from a huge comet or asteroid. The subsequent theory proposes that the rings never at any time formed part of the moon, but instead were components of bits and pieces that remained during the process of formation of the planet.
Saturn reflects the rays of the sun, and hence increases its brightness; but aided vision increases the visibility of the planet’s rings from the Earth. The astronomer, Galileo Galilei became the first person to observe Saturn’s array of rings in the year 1610. He did not identify them as rings because he only observed their edges. He falsely deduced that the system of rings were two moons the same as those he had observed around the planet Jupiter. About four and half decades later, Christian Huygens, a Dutch astronomer, discovered that what Galileo originally described as moons were in fact rings. Huygens had the advantage of using a much-advanced telescope than was used by his predecessor. Even though Saturn’s spectacular rings are very wide, spreading from the top of its surface to well past the orbits of the nearest moons, they are thin in diameter, equivalent to approximately one mile in width. The voyage by Pioneer 11 flyby discovered several attributes about the rings. They are composed of dust-sized particles up to huge mountain-sized particles. Their standard size is about four inches. These particles are tremendously cold and frozen water and different types of ices probably make them up. Observations also indicated a widespread cloud of liquid hydrogen that surrounds the rings.
The mission by Voyager I shade more light on the beauty, intricacy, and the occasional baffling character of the rings. Saturn’s rings are composed of thousands of little, thin ringlets with superseding spaces, hence the system of rings are noticeable to resemble the furrows in a phonographic record. Even the once perceived vacant space between ring A and B, the Cassini Division measuring 4,800 km in breadth, has many dozens of ringlets. Saturn’s dense major rings spread out from 7,000 km to 80,000 km beyond its equator. The major rings have components that range in diameter from less than one centimeter to a few meters. The rings have a mass of about 3 × 1019 kg. This mass is small compared to the massive weight of Saturn. The mission by Cassini space probe discovered that Saturn’s rings have their own independent atmosphere from that of the planet. Molecular oxygen gas (O2) forms the atmosphere. The gas is produced from reaction of ice water in the rings with the ultraviolet rays from the Sun. Hydrogen gas (H2) is also present. The planet exhibits intricate models of its brightness. Most of the changeability is derived from the varying nature of the rings, and this takes place after two phases of each orbit. Nevertheless, added to this is changeability because of the peculiarity of Saturn’s orbit that makes it to show dazzling lights in its northern hemisphere more than it displays in the southern hemisphere.
Among the known rings of Saturn, the B ring is the most outstanding in terms of largeness, brightness, and mass. It is approximately 5 to 15 meters thick, 2.8 × 1019 kg in mass. Obstruction of most of the light that passes across some parts of this ring is due to it having an optical depth that fluctuates from 0.4 to 2.5. The B ring has a massive deal of disparity concerning its density and brilliance, almost all of these still remains unexplained. Even though the B ring lacks spaces, the rings come into view as concentric ringlets. The arrangement of Saturn’s system of rings was until 1979 described as being completely the result of the action of gravitational forces. Then Voyager spaceship discovered radial elements in the B ring, called spokes. The description of the spokes cannot be in the similar manner since their persistence and movement in the region of the rings was not in line with the principles of orbital mechanics. The spokes become visible as dark in a backscattered illumination of light, and appear bright in forward-scattered illumination. The phase at which the change occurs is 45o.
Scientific investigation has not clearly come to terms with the spokes composition. The most acceptable theory proposes that they are made up of minute particles of dust, which through electrostatic forces of repulsion, makes them to float away from the main ring as they make turnings approximately synchronously with the magnetic atmosphere of this adorned planet. Scientific investigation has suggested that the electrical disturbances that generate the spokes are due to meteoroid collisions or lightning bolts in the planet’s surface. The spokes first appeared in Saturn’s B ring in 1979 rotating as a solid wheel. The mission by the Cassini spaceship noticed the spokes again after about two and half decades of waiting. When the spacecraft arrived at Saturn in early 2004, the spokes were not noticeable yet. Some astronomers suggested that the phenomenon of the spokes come into sight again in 2007. They based their speculative arguments on models trying to explain their development.
Regardless of this, the Cassini astronomers continued anticipating for the spokes in images of the B ring. Their relentless efforts bore fruit on 5 September 2005, when they saw images of the spokes. The phenomenon of the spokes appears to occur periodically (Beatty et al. 240). They vanish in the Saturnian midwinter/midsummer season and become visible as the planet approaches equinox. During the Cassini space probe mission, confirmations were made of the widely accepted suggestions that Saturn’s spokes are a periodic event that fluctuate with the planet’s 29.7-year orbit.
Works cited
Beatty et al. The new solar system. Cambridge: Cambridge University Press, 1999. Print.
Hamilton, Calvin. “Saturn.” Views of the Solar System. 2009. Web.
Henbest, Nigel and Marten, Michael. The new astronomy. Cambridge: Cambridge University Press, 1996. Print.