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Largest Kuiper Belt object

Largest Kuiper Belt object
Who
Pluto
Where
Not Applicable
When
14 July 2005

Pluto is the largest-diameter world in the Kuiper belt, with a diameter of 2376.6 kilometers (plus or minus 3.2 kilometers), as measured using images taken by New Horizons during its flyby on 14 July 2015. Eris is the largest-mass world in the Kuiper belt, with a mass of 1.67 times 10^22 kilograms (plus or minus 0.02 times 10^22 kg).

Eris' mass is 1.27 times that of Pluto. Eris' diameter is 2326 +/- 12 kilometers, measured by stellar occultation on 6 November 2010.