The Dwarf Planet – Essay Example
The paper "The Dwarf Planet " is a delightful example of an astronomy essay. The International Astronomers Union created a new category of the celestial body called dwarf planet in 2006. The dwarf planet category comprises of celestial bodies that are massive enough to have a spherical shape in the orbit around the Sun and that are not satellites. The significant factor that distinguishes a planet from a dwarf planet is the clearing of its orbit from debris and other materials whereas a dwarf planet need not fulfill this criterion. The categorization of the dwarf planet was immediately followed by the classification of three celestial bodies. They are Ceres - the largest asteroid is now a dwarf planet, the planet Pluto present in the Kuiper belt is demoted to a dwarf planet and Eris, the scattered disc object found far beyond the Pluto is a dwarf planet (Anissimov). The fourth dwarf planet of the solar system was named Makemake in 2008 though it was actually discovered in 2005. It is considered to be the largest object found in the outer solar system. Makemake is the fourth dwarf planet and the third plutoid. The surface of Makemake is covered by frozen methane and has a reddish color (Fourth dwarf planet named Makemake). The discovery of Eris partially influenced the International Astronomers Union to precisely define the word planet and categorize the dwarf planet. Though these celestial bodies are called the dwarf planet, it is not regarded as a subset of the planet, but it is considered under a completely different category. With the recognition of four dwarf planets, astronomers suspect as many as two hundred of its kind in distant locations of the solar system. The spherical criteria that are required to qualify for dwarf planethood require a diameter of 400 km (Anissimov).