Determining the dust environment of an unknown comet for a spacecraft fly-by: The case of ESA's Comet Interceptor mission

TL;DR

This paper introduces a statistical method to estimate the dust environment of unknown comets, accounting for large uncertainties in parameters like dust density, production rate, and brightness, crucial for spacecraft fly-by missions.

Contribution

It presents a novel statistical framework to evaluate dust environments of poorly known comets by exploring parameter space and quantifying uncertainties.

Findings

Dust density uncertainties are about 3 orders of magnitude.

Dust production rate can be estimated within 0.5 orders of magnitude if parameters are known.

A comprehensive ensemble approach captures the full range of possible dust environments.

Abstract

We present a statistical approach to assess the dust environment for a yet unknown comet (or when its parameters are known only with large uncertainty). This is of particular importance for missions such as ESA's Comet Interceptor mission to a dynamically new comet. We find that the lack of knowledge of any particular comet results in very large uncertainties (~3 orders of magnitude) for the dust densities within the coma. The most sensitive parameters affecting the dust densities are the dust size distribution, the dust production rate and coma brightness, often quantified by Af$\rho$. Further, the conversion of a coma's brightness (Af$\rho$) to a dust production rate is poorly constrained. The dust production rate can only be estimated down to an uncertainty of ~0.5 orders of magnitude if the dust size distribution is known in addition to the Af$\rho$. To accurately predict the dust environment of a poorly known comet, a statistical approach as we propose here needs to be taken to properly reflect the uncertainties. This can be done by calculating an ensemble of comae covering all possible combinations within parameter space as shown in this work.