Surface localization of gas sources on comet 67P/Churyumov-Gerasimenko based on DFMS/COPS data

TL;DR

This study reconstructs the surface gas emission patterns of comet 67P/Churyumov-Gerasimenko during 2015 using inverse modeling of data from Rosetta's instruments, revealing active regions and their variations over time.

Contribution

It introduces a method to map and analyze the temporal and spatial distribution of gas sources on the comet's surface based on in-situ measurements.

Findings

Identified nine most active emission areas on the comet.

Mapped the temporal evolution of gas emissions for four major species.

Compared emission rates between northern and southern hemispheres.

Abstract

We reconstruct the temporal evolution of the source distribution for the four major gas species H2O, CO2, CO, and O2 on the surface of comet 67P/Churyumov-Gerasimenko during its 2015 apparition. The analysis applies an inverse coma model and fits to data between August 6th 2014 and September 5th 2016 measured with the Double Focusing Mass Spectrometer (DFMS) of the Rosetta Orbiter Spectrometer for Ion and Neutral Analysis (ROSINA) and the COmet Pressure Sensor (COPS). The spatial distribution of gas sources with their temporal variation allows one to construct surface maps for gas emissions and to evaluate integrated productions rates. For all species peak production rates and integrated productions rates per orbit are evaluated separately for the northern and the southern hemisphere. The nine most active emitting areas on the comet's surface are defined and their correlation to emissions for each of the species is discussed.