This astronomical study will define the development of Pluto from being a planet to a “dwarf planet” in the solar system. Pluto is a planet with about 30 to 49 astronomical units away from the sun, and it takes about 5 hours for the light of sun to reach its surface. Pluto also has an orbit of 248 years, which makes the longest orbital time period for a planetary object in the solar system. The mass of Pluto is 1.303±0.003)×1022 kg and the radius of the planet is 0.1863 Earths. The small size of the planet makes it around one-sixth of the size of the moon, which made it the smallest planet in solar system. However, the discovery of Eris (another dwarf planet) made Pluto much smaller, and this size ratio inspired the international Astronomical Union (IAU) to alter its definition of a celestial body. In fact, Pluto was soon changed to be a “dwarf planet”, since it did not have the …show more content…
However, the designation of dwarf planet is a stronger designation because Pluto actually orbits the sun. Certainly, Eris has a very chaotic orbital range, but the gravity of the sun is continually affecting the orbit of these objects,, which them objects within the solar system. This is another reason why Pluto should be called a dwarf planet, since it has a far-reaching orbit around the sun. The previous definition of debris in the transneptunian region also makes objects, such as Pluto, far larger than the large icy objects that do not have the same shape as a spherical planetary object. Once gain, the fact that Pluto orbits around the sun and the similar shape it shares with larger planets is a rationale way to describe a dwarf planet. In my opinion, I have no problem with calling Pluto a dwarf planet because of a solar orbital range and the size/shape ration that are very similar to larger