What does the higher density of Eris compared to Pluto suggest about its formation history?

Answer

It likely formed closer to the Sun before being scattered outward.

The high density of Eris indicates a higher ratio of rock to ice compared to Pluto. This composition suggests that the object formed in a region of the solar system closer to the Sun where rocky material was more abundant. It was subsequently pushed into its current distant orbit due to gravitational interactions with giant planets.

What does the higher density of Eris compared to Pluto suggest about its formation history?
SpaceastronomylargestObjecttrans-Neptunian object