Fig. 2
From: A dynamics based procedure for clustering and classifying space debris
(a) The distribution in (a, e, i) at the initial time of two groups of fragments generated by the break-up of two satellites. (b) The distribution of the same groups choosing each fragment at a controlled shuffled time. (c) Same as (b), but without colours. (d) DBSCAN correctly provides two clusters, shown in the projected plane (e, i), when using proper elements at shuffled times. (e) DBSCAN erroneously provides three clusters, projected in the plane (e, i), when using mean elements at shuffled times.
