Essay on The Earth And The Sun

1340 Words Dec 9th, 2016 6 Pages
Seaghan Kinneen

8.5 billion miles from the Sun, over ninety-one times the distance between the Earth and the Sun, stands the newest addition to the Solar System. 2014 UZ224, located some 4.83 billion miles beyond Pluto, joined Ceres, Eris, Haumea, Makemake, and the aforementioned Pluto, as the most recently discovered Solar System Dwarf Planet.
To understand the definition of a Dwarf Planet, one must understand the definition of a regular planet. In a 2006 assembly that has gained notoriety for “killing” the planetary status of Pluto, the International Astronomical Union, or IAU, resolved definitions for both planets and dwarf planet. They outlined four criteria that determine planetary status for celestial bodies. The first is that the celestial body must be in orbit around the sun. The second is that the celestial body must have a large enough mass that it reaches hydrostatic equilibrium, where gravity, which is directly proportionate to mass, is able to overcome rigid body forces. When this happens, the celestial body assumes a nearly round shape. The necessary mass to reach hydrostatic equilibrium varies with the composition of the celestial body. For example, Mimas, an icy moon of Saturn, is able to assume hydrostatic equilibrium with a diameter of 397 kilometers. However, Pallas, an asteroid made of rock, does not assume hydrostatic equilibrium with a diameter of 532 kilometers. The third criterion is that the celestial body must “clear the neighborhood” around its…

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