The dwarf planet Eris could be smaller than Pluto

It has used the occultation of a star by Eris to determine its size accurately

 
Artistic view of ERIS exoplanet
26/10/2011
The most distant ocultation

Imagen del exoplaneta Eris

Artistic view of Eris

 

Reference: 

"A Pluto-like radius and a high albedo for the dwarf planet Eris from an occultation" B. Sicardy et al. Nature

More info: 

José Luis Ortiz, ortiz [at] iaa.es 622233836

Press release: 
PDF icon Press release about dwarf exoplanet ERIS