The dust environment of Main-Belt Comet P/2012 T1 (PANSTARRS)

TL;DR

This study models the dust environment of Main-Belt Comet P/2012 T1, revealing sustained dust emission over several months, with anisotropic ejection patterns and estimated dust mass between 6 and 25 million kilograms.

Contribution

It provides the first detailed dust environment model for P/2012 T1, highlighting anisotropic emission and seasonal activity patterns.

Findings

Dust ejection lasted 4-6 months.

Estimated total dust mass is 6-25 million kg.

Anisotropic emission pattern is favored over isotropic.

Abstract

Main-Belt Comet P/2012 T1 (PANSTARRS) has been imaged using the 10.4m Gran Telescopio Canarias (GTC) and the 4.2m William Herschel Telescope (WHT) at six epochs in the period from November 2012 to February 2013, with the aim of monitoring its dust environment. The dust tails brightness and morphology are best interpreted in terms of a model of sustained dust emission spanning 4 to 6 months. The total dust mass ejected is estimated at $\sim$6--25$\times10^6$ kg. We assume a time-independent power-law size distribution function, with particles in the micrometer to centimeter size range. Based on the quality of the fits to the isophote fields, an anisotropic emission pattern is favored against an isotropic one, in which the particle ejection is concentrated toward high latitudes ($\pm45^\circ$ to $\pm90^\circ$) in a high obliquity object ($I$=80$^\circ$). This seasonally-driven ejection behavior, along with the modeled particle ejection velocities, are in remarkable agreement to those we found for P/2010 R2 (La Sagra) \citep{Moreno11a}.