Newly Disrupted Main Belt Asteroid P/2010 A2

TL;DR

This paper reports on the discovery and analysis of P/2010 A2, a main-belt asteroid likely resulting from a recent disruption event, providing rare observational evidence of asteroid disruption mechanisms.

Contribution

It presents high-resolution Hubble observations of P/2010 A2, offering direct evidence of asteroid disruption in the main belt for the first time.

Findings

Discovered a main-belt asteroid with a comet-like tail

Observed dust particles formed in early 2009

Provided evidence supporting disruption as a key asteroid evolution process

Abstract

Most main-belt asteroids are primitive rock and metal bodies in orbit about the Sun between Mars and Jupiter. Disruption, through high velocity collisions or rotational spin-up, is believed to be the primary mechanism for the production and destruction of small asteroids and a contributor to dust in the Sun's Zodiacal cloud, while analogous collisions around other stars feed dust to their debris disks. Unfortunately, direct evidence about the mechanism or rate of disruption is lacking, owing to the rarity of events. Here we present observations of P/2010 A2, a previously unknown inner-belt asteroid with a peculiar, comet-like morphology that is most likely the evolving remnant of a recent asteroidal disruption. High resolution Hubble Space Telescope observations reveal an approximately 120 meter diameter nucleus with an associated tail of millimeter-sized dust particles formed in February/March 2009, all evolving slowly under the action of solar radiation pressure.