Eris and Pluto: Are these distant dwarf planets actually identical twins?
Astronomers have finally measured the diameter of the remote dwarf planet Eris. By observing it pass in front of a distant star, researchers discovered that this icy world is nearly identical in size to Pluto, revealing a surprising symmetry in the outer solar system.
In late 2010, telescopes in Chile, including the TRAPPIST instrument at the La Silla Observatory, captured Eris as it occulted a faint star. This rare alignment allowed astronomers to determine the dwarf planet's diameter with unprecedented accuracy for the first time.
The data confirms that Eris is an almost perfect twin to Pluto in terms of size. Furthermore, the object exhibits a highly reflective surface, which indicates that it is likely coated in ice—possibly a frozen atmosphere. This finding provides a clearer picture of the composition of these distant, icy bodies orbiting far from the Sun.
