A dwarf planet - Eris
Eris is a dwarf planet and is about the same size as Pluto but is three times further away from the Sun and Dysnomia is the moon of Eris. The planet was discovered on Oct. 21, 2003, by M.E. Brown, C.A. Trujillo, and D. Rabinowitz at the Palomar Observatory. It is named after "Eris", the ancient Greek goddess of conflict and discord. The moon was named after the goddess's daughter. Similar huh!?
Eris would be about the size of a popcorn kernel if the Earth were the size of a nickel. It rotates once every 25.9 hours, making its day close to ours in duration. Eris is part of the Kuiper Belt, a collection of objects that orbit in a disc-like region outside Neptune's orbit. Thousands of miniature ice worlds have evolved early in the history of our solar system, around 4.5 billion years ago, in this faraway domain but its internal structure is still unknown by the scientists.
Scientists discovered somewhat that the surface temperature of this planet fluctuates from -217 degrees up to -243 degrees and its freezing atmosphere is due to the farness from the Sun. Due to its freezing weather, no life could exist there but we never know! There are still many things yet to be known about this wonderful mysterious dwarf planet i.e. magnetosphere, rings, structure, and so on but sooner or later, scientists will come up with more beautiful information about this neighbor of our known solar system.