Trans-Neptunian objects: sizes, colors, and albedos by semimajor axis and eccentricity

by Wm. Robert Johnston
last updated 15 March 2015

This plot represents all known trans-Neptunian objects and Centaurs as of February 2015 plotted by orbit eccentricity vs. semimajor axis. Symbols represent the best current estimates of relative sizes, albedos, and colors for these objects. The ten objects known or estimated to be largest than the largest asteroid, Ceres, are labeled: Pluto (and its moon Charon), Eris, Makemake, Haumea, (225088) 2007 OR10, 2013 FY27, Quaoar, Sedna, and (84522) 2002 TC302.

A total of 1,899 outer solar system objects and 85 companions are represented, of which 9% have measured diameter and albedo and 18% have measured visible colors. For the remainder, colors and albedos are based on the averages for dynamical classes, grouped as: Centaurs, Cubewanos, Plutinos, other resonance objects, scattered disk objects, and all other TNOs. For more information see these pages:


© 2015 by Wm. Robert Johnston.
Last modified 15 March 2015.
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