Eris is the the most massive dwarf planet and is also the furthest from the Sun.

Eris Dwarf Planet Profile

Mass: 16,700,000,000,000 billion kg
Diameter: 2,326 km (+- 12km)
Known Moons: 1
Notable Moons: Dysnomia more info
Orbit Distance: 10,120,000,000 km (68.01 AU)
Orbit Period: 560.90 Earth Years
Surface Temperature: -231°C
Discovery Date: January 5th 2005
Discovered By: M.E. Brown C.A. Trujillo & D.L. Rabinowitz

Size of Eris Compared to the Earth

Size of Eris

Facts about the Dwarf Planet Eris

Eris was once considered for the position of tenth planet:
Eris is the most massive dwarf planet in the Solar System, exceeding Pluto’s mass by 28%. As such, it was a serious contender to be a tenth planet but failed to meet the criteria set out by the International Astronomical Union in 2006.

Eris was named after the Greek goddess of discord:
Fittingly, picking a name for the object took unusually long – more than 1.5 years after its discovery in 2005. Some of the rejected names were Xena, Lila, and Persephone (Pluto’s wife).

Eris may be the largest dwarf planet:
Eris is unquestionably the most massive of the known dwarf planets and was once thought to be the largest due to its relative brightness. After a stellar occultation in 2010 its diameter was calculated to be smaller than previously thought and more recent measurement suggested Pluto was larger than thought, however there is enough of a margin of error that either could be the largest.

All the objects in the Asteroid Belt could fit inside Eris:
Eris is still smaller than the Earth’s Moon, having about two thirds of the Moon’s diameter and one third of its volume.