In the Beginning

The night sky is a magnificent sight to see. It is filled with stars and other celestial bodies. People throughout the centuries have given names to these objects, often giving them mystical meanings. We often wonder how this all began. There is more than one theory addressing this.

Our sun, Sol, is estimated to be around 4.5 billion years old. It contains about 99 percent of the entire mass of he solar system. It is a G class star, which places it in the middle as far as stars go. There are nine (or eight, depending on which camp you are in) planets, each in an elliptical orbit around the sun. There are four terrestrial and four Jovian planets that make the main eight planets. Pluto, the controversial planet, is considered a Kuiper Belt object, possibly captured by the sun's gravitational force. Despite the different makeups of each of these objects, they all have common origins

The accretion theory holds that the solar system was formed from the solar nebula. This nebula separated from the interstellar medium around 7 billion years ago. As this nebula began to contract due to its own gravitational force, its momentum through space forced it to start spinning, creating a disk with a mass in the middle. This mass of matter eventually reached the temperature and pressure needed to start the nuclear fission that led to the creation of the sun.

The particles of dust that are swirling around the newly created sun began to coalesce into larger masses. These masses went through countless collisions and further condensation, creating the planets, moons, comets, and other celestial bodies. During the chaos, large amount of gravitational forces ripped apart less stable masses and assisted in the formation of other masses, these larger masses are what constitute the planets in our solar system.

The accretion theory is probably the most widely accepted theory of creation of the solar system, as we know it today. It is probably the answer for the formation of other planetary systems in the universe. By understanding our own solar system formation, we can begin to understand how the universe really came to be the spectacular force that it is.

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