Dwarf planets


The term dwarf planet was much used in recent years and is part of a categorization tripartite bodies that are orbiting around the sun . This term was adopted in 2006 after the discovery of objects that were beyond the orbit of Neptune and that were comparable in size to Pluto . Since then, it has been used to describe many objects in our solar system, replacing the old system of classification which claimed that there were nine planets.


What are dwarf planets?

The dwarf planets are the bodies of the solar system that have a mass sufficient for its gravity exceeds the force that has a rigid body, and found orbiting around the sun to the as do the other planets.


The term has also produced some confusion and controversy, as its accuracy is questioned. However, five bodies are recognized within our solar system as dwarf planets , six more could be recognized in the next few years, and up to 200 or more could exist within the extent of the Kuiper Belt.


What are the dwarf planets

The dwarf planets are as follows:

  • Ceres : it was discovered in 1801 and is the smallest of all because it measures only 952 km in diameter. It is located between Mars and Jupiter in the Asteroid Belt . It has all the conditions of a planet, ice on the surfaces, oceans , an extremely cold temperature , characteristics that make it ideal for hosting missions. The quality of life on this planet would be similar to that of Antarctica.
  • Pluto – Charon : it is what we know as planet number nine in our solar system but as of 2006 , it is no longer considered a true planet . It is believed to be a binary planetand has previously been classified as a planetoid as well.
  • Haumea : it measures approximately 1600 km. Its surface is made up of 90% frozen water because it is a planet that is very far from the sun, so it is also difficult to study. It was discovered in 2003 . It has two moons and its name is derived from the Hawaiian goddess of fertility . It is shaped like an egg and doesn’t really look like a plant at all. One year on this planet equals 284 Earth years.
  • Eris : measures 2,300 km in diameter, which makes it smaller than Pluto, although it is three times as far from the Sun. It was discovered in 2005 and is considered the most distant space object in the solar system . with the exception of some kites. Its surface is formed of frozen methane , it is reddish in color although it has a bluish appearance thanks to the methane.
  • Makemake : it was the last dwarf planet to be discovered in 2008. It is a rather difficult planet to observe due to its distance and there is not much information about it. It got its name from the god Make-Make , the creator of the world. The lack of satellites does not allow its exact measurement , since it is through them that this calculation can be made.


The main characteristics of the dwarf planets are the following:

  • They are orbiting around the sun .
  • They have sufficient mass to have an almost spherical shape .
  • It shares its orbital space with other bodies that have a similar size.
  • All dwarf planets vary in size , mass , duration of orbit around the Sun, and duration of rotation on its axis.
  • They are so small that many of them can fit inside the Earth .

Why are they called dwarf planets

The term was created by the International Astronomical Union to name a new class of celestial bodies, which are not the same as a planet but which also do not fall within the minor body classification of the solar system.

How they differ from normal planets

There are different criteria that establish why the dwarf planets are different from the planets that we are used to knowing. Dwarf planets do not meet some of the following requirements to be called planets, and their differences are based on them:

  • Have an orbit around the sun .
  • Not being a satellite of another body .
  • Be solid enough so that its own gravity rounds the shape of the celestial body to a point of hydrostatic equilibrium . In other words, make it spherical .
  • The last point includes that the planet has cleared the vicinity of its orbit of most of the smaller objects that may be around it.

Examples of dwarf planets

Some examples of dwarf planets in the solar system in order of proximity to the sun are as follows:

  • Ceres, which is the only one in the asteroid belt.
  • Pluto
  • Haumea
  • Makemake
  • Eris

To mention examples it is important to also mention that the orbit of Pluto intersects the orbit of Neptune , and these dwarf planets are known as trans-Neptunian objects . Dwarf planets are trans-Neptunian objects. Some examples of these planets are:

  • Charon
  • Sedna
  • Orcus
  • Quaoar

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