Nesvorny HCM Asteroid Families Bundle V2.0

The proper elements of asteroids are obtained from the instantaneous orbital elements by removing periodic oscillations produced by gravitational interactions with planets. They are unchanging in time, at least if chaotic dynamics and non-gravitational forces could be ignored, and can therefore be used to identify fragments of major collisions (asteroid families) that happened eons ago. Here we publish a new catalog of proper elements for 1.25 million main belt asteroids. A systematic search for families yielded 153 cases not reported in Nesvorny at al. (2015) -- 17 of these cases were identified in various other publications, 136 cases are new discoveries. There are now 274 families in the asteroid belt in total (plus a handful of new families in the resonant Hilda population). The present package contains member identifications for 153 new families.