Analysis of trans-Neptunian and centaur colours: continuous trend or grouping?

Abstract

We report the results of the first statistical analysis of colours (B - V, V - R, V - I, and V - J) of the Trans-Neptunian and Centaur populations. Using the same statistical techniques applied to define the current asteroid taxonomy, we find a continuous spread of the objects between neutral colour to very red. Pushing further the analysis, the TNOs may be split into four groups. The differences in colour are interpreted as a consequence of the TNOs evolution (i.e. collisional history, space weathering, ...).