Electrostatic Dust Ejection From Asteroid (3200) Phaethon With the Aid of Mobile Alkali Ions at Perihelion

TL;DR

This paper proposes that electrostatic lofting aided by mobile alkali ions at high temperatures explains Phaethon's dust ejection activity at perihelion, aligning with observed dust tail data and predicting higher mass-loss rates for larger particles.

Contribution

It introduces a novel electrostatic model involving mobile alkali ions to explain dust ejection from Phaethon, consistent with observations and predicting significant mass loss for larger particles.

Findings

Model matches observed dust tail mass-loss rates.

Predicts higher mass-loss rates for millimeter-sized particles.

Supports electrostatic lofting as the mechanism for Phaethon's activity.

Abstract

The asteroid (3200) Phaethon is known to be the parent body of the Geminids, although meteor showers are commonly associated with the activity of periodic comets. What is most peculiar to the asteroid is its comet-like activity in the ejection of micrometer-sized dust particles at every perihelion passage, while the activity of the asteroid has never been identified outside the near-perihelion zone at $0.14~\mathrm{au}$ from the Sun. From the theoretical point of view, we argue that the activity of the asteroid is well explained by the electrostatic lofting of micrometer-sized dust particles with the aid of mobile alkali ions at high temperatures. The mass-loss rates of micrometer-sized particles from the asteroid in our model is entirely consistent with the values inferred from visible observations of Phaethon's dust tail. For millimeter-sized particles, we predict three orders of magnitudes higher mass-loss rates, which could also account for the total mass of the Geminid meteoroid stream by the electrostatic lofting mechanism.