The Formation of Terrestrial Planets versus the Formation of Gas Giant Planets

In the solar system, there are eight planets orbing the sun. Four of which are the inner planets thus, meaning they are smaller in size, have solid terrestrial surfaces and little to no atmosphere surrounding the planets. These planets include (in order from Sun to Asteroid belt) Mercury, Venus, Earth, and Mars, as illustrated in Figure 1. The four remaining planets in the solar system are known as, outer planets- these are the gas giants. These planets include, (from asteroid belt outward) Jupiter, Saturn, Uranus, and Neptune. As illustrated in Figure 1. These planets are the massive in size, have large atmospheres and are non- terrestrial- made of gas, such …show more content…
At this time, when gravity forced together a low- density, interstellar gas, dust, it created a nebula.1When an over density occurred in the massive nebula, it collapsed causing a much smaller nebula with a much higher concentration. Initially, the motions of the cloud particles were random. However, the nebula had a net rotation and as the collapsing proceeded, the rotation of the cloud was increasingly speed up due to conservation of angular momentum.1 The continuous rotating motion resulted in the nebula becoming a disk shape- where the majority of the mass concentrated near the center; creating the sun. See figure 2. As the sun was created, it obtained 99.8% of the mass in the universe and near its core, reached temperatures near 10 million K. After about 50 million years, the sun reached a point in which is reached an equilibrium between downward gravitational force and higher force of pressure. At this point the formation of the eight planets begin. The thin disk beside the sun gave birth to the remaining planets, asteroids, Moons and other celestial objects. As the sun obtained 99.8% of the mas, this disk only weighed only 0.2% of total mass of the solar nebula. The disk was composed of; 75% hydrogen, 25% helium, and all other elements comprising only 2% of the total mass. The disk reached several thousand degrees near the center due to the release of gravitational energy. The planets closer to the sun, where the temperature was higher were created out of the elements in the 2% category. These were only the densest and heaviest compounds. They include, compounds of aluminum, titanium, iron, and nickel. These elements created the inner planets because they are closer and more available for the formation at the specific location without collapsing. Further from the sun, the material used to form the gas giants were primarily gaseous because hydrogen and helium remain gaseous even at very low