The Solar Nebula Model Essay

The planets in the solar system, except the Pluto, are classified as either terrestrial or Jovian planet. The Jovian comprises of the Uranus, Jupiter, Neptune, and Saturn while the terrestrial planets are the Venus, Earth, and Mercury. The significant difference between them is their surfaces.  The terrestrial planets have a rocky surface, with metals deep in its interior surfaces. On the other hand, Jovian planets have gaseous surfaces hence the name gas giants because they make up mostly gases (Ohno &  Okuzumi 2017). Also, terrestrial planets are nearer to the sun compared to the Jovian planets. The layer of gases surrounding the surface makes up the atmosphere.  There is an abundance of the of the hydrogen and helium gases in the atmosphere of the Jovian planets making them less dense. However, its core is thicker than that of the terrestrial planets.  In contrary, the terrestrial planet's atmosphere consists of the carbon dioxide and the nitrogen gases and frequently affected by dust storms.

 According to Wissman and A'Hearn, the idea in support of the solar nebula model postulates that the planets and the sun were formed through the sudden fall down of the rotating cloud of interstellar dust and gas (2015). The collisions allowed the sticking together and making of a more massive particle in a process called accretion forming the planetesimals. These planetesimals formed rocks and metal making up 0.6% of the materials in the solar nebula hence the planets could not grow and could not exert an enormous pull on the helium and the hydrogen gases. Jovian planets are different from these because planetesimals are from the abundance of ice hence could not grow too much larger sizes. It then became the core which was not able to capture the hydrogen and helium gases becoming large, gaseous and low-density with dense solid cores.

References

Weissman, P. R., & A'Hearn, M. (2015, November). Accretion of cometary nuclei in the solar nebula: boulders, not pebbles. In AAS/Division for Planetary Sciences Meeting Abstracts(Vol. 47).

Ohno, K., & Okuzumi, S. (2017). A Condensation–coalescence Cloud Model for Exoplanetary Atmospheres: Formulation and Test Applications to Terrestrial and Jovian Clouds. The Astrophysical Journal, 835(2), 261.