P/2006 VW139: a main-belt comet born in an asteroid collision?

Abstract

In this paper we apply different methods to examine the possibility that a\nsmall group of 24 asteroids dynamically linked to main-belt comet P/2006 VW139,\nrecently discovered by the Pan-STARRS1 survey telescope, shares a common\nphysical origin. By applying the Hierarchical Clustering and Backward\nIntegration methods, we find strong evidence that 11 of these asteroids form a\nsub-group which likely originated in a recent collision event, and that this\ngroup includes P/2006 VW139. The objects not found to be part of the 11-member\nsub-group, which we designate as the P/2006 VW139 family, were either found to\nbe dynamically unstable, or these are likely interlopers which should be\nexpected due to the close proximity of the Themis family. As we demonstrated,\nstatistical significance of P/2006 VW139 family is >99 per cent. We determine\nthe age of the family to be 7.5 +/- 0.3 Myr, and estimate the diameter of the\nparent body to be about 11 km. Results show that the family is produced by an\nimpact which can be best characterized as a transition from catastrophic to\ncratering regime. The dynamical environment of this family is studied as well,\nincluding the identification of the most influential mean motion and secular\nresonances in the region. Our findings make P/2006 VW139 now the second\nmain-belt comet to be dynamically associated with a young asteroid family, a\nfact with important implications for the origin and activation mechanism of\nsuch objects.\n