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Eris Dwarf Planet – Facts and Information

eris dwarf planet

Eris dwarf planet used to be the 10th planet of our solar system for a short period of time. Eris is the most massive and second-largest dwarf planet in the solar system. It is the largest object of our solar system that has not been visited by any spacecraft so far. 

The dwarf planet Eris was discovered in January 2005 by a team led by Mike Brown in Palomar Observatory. It is a Trans-Neptunian Object (TNO) and located in the scattered-disk region. The Eris was named after the Greek goddess of strife and discord in September 2006.

Characteristics of Eris:-

  • Orbital period: 204200 days (559 earth years)
  • Average orbital speed: 3.43 km/sec around the sun
  • The average distance from Sun: 67.78 AU
  • Mean radius: 1165 km
  • Mass: 1.65 × 1022 kg (0.0028 times of earth)
  • Volume: 6.6 × 109 km3 
  • Average density: 2.5 gm/cm3  
  • Surface gravity: 0.82 m/sec22 (0.084 times of earth)
  • Escape velocity: 1.38 km/sec
  • Average surface temperature: -231 °C
  • Moons: 1 known moon

In this article, we have mentioned the best Eris dwarf planet facts and the most interesting information. 

Eris dwarf planet facts:- 

Discovery of the Eris

Who discovered Eris? Eris was discovered on 5 January 2005 in Palomar Observatory California United States, by an American astronomer Mike Brown and his team. The team has discovered the Makemake dwarf planet

It was classified as a dwarf planet on 24 August 2006, when the International Astronomical Union (IAU) first time defined the term planet & dwarf planet. In the time period of 2005 to 2006, most of the astronomers considered it as the tenth planet of our solar system. The discovery of this minor planet is considered as a reason that Pluto is no longer a planet. 

Most massive dwarf planet

Eris is the most massive dwarf planet of our solar system. The largest dwarf planet is Pluto but it has less mass compare to Eris. The mass of the Eris is around 1.6 × 1022 kg, whereas the mass of the Pluto is around 1.3 × 1022 kg. Eris mass is 23% of the earth’s moon, though Pluto’s mass is approximately 18% of the Moon.  

Second largest dwarf planet 

It is the second-largest dwarf planet of our solar system. The Eris diameter is around 2330 km, whereas the largest dwarf planet Pluto diameter is almost 2380 km. The size of the Eris dwarf planet in volume is approximately 6.6 × 109 km3

Farthest dwarf planet (Eris location)

Eris is a Trans-Neptunian Object (TNOs – objects beyond to planet Neptune) located in the scattered disc region of the solar system. It is the farthest dwarf planet with an average distance of around 67.78 AU from the sun.

Eris is closer to Sun than Pluto for some time

‘Eris dwarf planet orbit?’ ‘One day and one year on Eris?’ 

The dwarf planet Eris completes one orbit around the Sun in almost 559 earth years, whereas it takes around 25.9 hours to complete its one day. This dwarf planet is located beyond the Kuiper belt region and has the orbital characteristics as a scattered-disk object (SDO). 

The closest approach to the sun (perihelion) is almost 37.9 AU, whereas the farthest distance from the sun (aphelion) is around 97.6 AU. Its orbit is highly eccentric that brings it closer to the Sun than Pluto for some time. (Pluto’s aphelion point is 49.3 AU, whereas Eris perihelion point is only 38.3 AU from the sun.) It reaches near to the Neptune’s orbit during its perihelion. 

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One of the coldest object (Eris temperature)

Though Eris is one of the farthest objects in our solar system, so obviously it would have a low surface temperature. The average temperature on this dwarf planet is around 42 K. The minimum approximate temperature is around 30 K, whereas the maximum temperature could reach up to 55 K on it. 

Eris moon 

Eris dwarf planet has only one known moon and its name is “Dysnomia”. It was discovered in October 2005. The Dysnomia is the second-largest moon of a dwarf planet after the Charon (Pluto’s moon). Dysnomia is named after the Greek goddess of lawlessness, who was Eris’s daughter. 

Read here about 4 other dwarf planets:-