Eris

Eris is a dwarf planet in our solar system, located in the Kuiper Belt beyond Neptune. It was discovered in 2005 and is named after the Greek goddess of strife and discord. Eris is one of the largest known dwarf planets and has a highly elliptical orbit that takes about 560 years to complete.

Characteristics of Eris

• Size: Eris is about 1/4 larger than Pluto, making it one of the largest known dwarf planets.
• Composition: Its surface is composed of rock and frozen methane, water, and nitrogen.
• Moons: Eris has one known moon called Dysnomia, named after the daughter of Eris in Greek mythology.
• Orbit: Eris has a highly eccentric orbit that takes it from about 38 to 98 astronomical units (AU) from the Sun.

Importance of Eris

Studying Eris and other objects in the Kuiper Belt provides valuable insights into the formation and evolution of our solar system. Eris's discovery also led to the reclassification of Pluto from a planet to a dwarf planet, sparking a reevaluation of how we define and categorize celestial bodies in our solar system.

Study Guide

1. What is the name of the dwarf planet located in the Kuiper Belt beyond Neptune?
   Answer: Eris
2. When was Eris discovered?
   Answer: 2005
3. What is the name of Eris's moon?
   Answer: Dysnomia
4. What is Eris's surface composed of?
   Answer: Rock and frozen methane, water, and nitrogen
5. What led to the reclassification of Pluto?
   Answer: The discovery of Eris and other similar objects in the Kuiper Belt

By studying Eris, scientists continue to expand our understanding of the outer regions of our solar system and the diverse range of celestial bodies that reside there.