Dwarf Planets vs Planets: Dwarf Planets List in Order

In the definition of planets and dwarf planets, there is only one significant difference that dwarf planets has not cleared the neighborhood objects around its orbit. In 2006, the International Astronomical Union (IAU) categorized the objects orbiting the sun into three divisions:

• Planets
• Dwarf Planets
• Small Solar System Bodies

In around 1800 AD astronomers have discovered several celestial bodies between planet Mars and Jupiter. They used to consider these bodies as a planet. But when the number of bodies increases continually astronomers classify another category and started using the word asteroid for some celestial bodies. 

Pluto was discovered in 1930 and then astronomers used to classify the solar system celestial bodies into 9 planets and several hundreds of asteroids and comets. But in 2005 after the discovery of Eris (a dwarf planet), IAU and astronomers proposed a definition of planets and dwarf planets in our solar system.

 

Dwarf Planets vs Planets

Here in this article, we have mentioned what is the definition of dwarf planets vs planets? This definition is given according to the International Astronomical Union (IAU).

According to IAU, the planet is a celestial body that:

1. orbit around the sun,
2. has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium shape (almost round shape),
3. has cleared the neighborhood around its orbit.

According to IAU, the dwarf planet is a celestial body that:

1. orbit around the sun,
2. has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium shape (almost round shape),
3. has not cleared the neighborhood around its orbit,
4. is not a satellite.

So there are only one difference in-between planets and dwarf planets that dwarf planets have some neighborhood objects in its orbit. These neighborhood objects may be some asteroids, debris, and smaller bodies. 

 

List of Planets and Dwarf Planets in our Solar System

According to the International Astronomical Union (IAU), there are 8 planets and 5 officially recognized dwarf planets in our solar system.

These 8 planets are Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune. Whereas 5 dwarf planets in our solar system are Pluto, Ceres, Eris, Haumea, and Makemake. These 5 are officially accepted by IAU. 

There are some other dwarf planets (near-certain) in our solar system that are not officially recognized by IAU:

• Quaoar
• Sedna
• Orcus
• 2007 OR₁₀
• Salacia
• 2002 MS4
• 10 Hygiea. 

Those above 7 mentioned dwarf planets that are officially not recognized by IAU and comes in the category of “near-certain” or “most likely” dwarf planets. Though there may be more than 10,000 of the near-certain dwarf planets in our solar system. And only in the Kuiper belt region, there may be over 200 in numbers of it. 

Dwarf Planets in Order

The naming committee of the IAU has decided some of the Trans-Neptunian Objects as a most likely dwarf planet. (Transneptunian objects are those object that orbits around the sun with higher distance than planet Neptune).

Here we have given a list of dwarf planets in order with increasing distance from the sun and where they located in the solar system. In the below table both dwarf planets are listed like ‘near-certain’ as well as ‘IAU defined’. 

Dwarf Planets	Distance from sun	Location in solar system
Ceres	2.77 AU	Asteroid belt
Orcus	39.40 AU	Kuiper belt
Pluto	39.47 AU	Kuiper belt
Haumea	43.20 AU	Kuiper belt
Quaoar	43.69 AU	Kuiper belt
Makemake	45.56 AU	Kuiper belt
2007 OR10	67.38 AU	scattered disc
Eris	67.78 AU	scattered disc
Sedna	506.70 AU	Detached

As given in the table, Ceres is the closest dwarf planet in our solar system and it is also IAU-defined. The IAU defined farthest dwarf planet is Eris and is located in the scattered disc with a distance of around 67.78 AU from the sun. 

 

1. Largest Dwarf Planet (Pluto)

Pluto is the largest dwarf planet in our solar system with a diameter of approximately 2380 km. It used to be a planet but in 2006 IAU decided to re-classify it into the dwarf planets category. Though Pluto has a small size compared to our earth, still it has 5 moons/natural satellites.

To know more especially about Pluto, check the following link: Pluto facts and information: Dwarf planet pluto

 

2. Smallest Dwarf Planet (Ceres)

Ceres is the smallest dwarf planet in our solar system with a diameter of approximately 940 km. It is located in the region of the Asteroid belt. The astronomers have discovered the ceres at around in 1801. So this is the earliest known dwarf planet by astronomers.

Read in detail:- Ceres dwarf planet: Amazing facts and information

 

New dwarf planets:-

According to officially recognized by International Astronomical Union (IAU) new dwarf planets are Eris, Haumea, and Makemake.

3. Eris

Eris has one known moon and was discovered in January 2005. In between 2005 to 2006 it was considered as 10th planet of our solar system by most of the astronomers. Eris re-classified into the dwarf planet in 2006 by IAU. 

4. Haumea

Haumea was discovered in December 2004. It was not considered as a dwarf planet by the naming committee of IAU till July 2008. It has 2 moons that orbit around it.

5. Makemake

Makemake was discovered in July 2005 and announced as a dwarf planet by the naming committee of IAU in 2008. It has one known natural satellite. This dwarf planet was discovered around Ester (a festival) 2005, so it is also known as an ‘Easterbunny’. 

Read about:- Makemake Facts: Dwarf planet Makemake

 

These are the 5 dwarf planets in our solar system recognized and considered by IAU. There are thousands of more objects in the solar system to discover that maybe a dwarf planet or most likely it.