Statistical analysis of the electric field measurements from the Rosetta spacecraft in the plasma environment of comet 67P/Churyumov-Gerasimenko

Abstract: Comets are a key to understanding the early stages of the solar system. They were hereat its formation and have not evolved ever since, which means they are our best shotat learning the processes that led to the formation of the solar system as we know ittoday. Yet, our knowledge about these bodies is very limited. They are far from theEarth and small, which makes it complicated and expensive to reach them. But thestudy of the chemistry and geology of comets is not the only goal of the scientific community.The plasma environment of these astronomical bodies could also give answersto many questions regarding the science of plasma physics, such as the interaction ofthe solar wind with plasmas. Answering some of these questions was an objectiveof the Rosetta Mission. Before its launch, only three space missions out of eight targettingcomets had plasma instruments onboard. Rosetta carried several instrumentsdesigned to analyse the plasma environment of comet 67P/Churyumov-Gerasimenko.We were able to perform a statistical analysis of the electric field spectrum in the vicinityof comet 67P/Churyumov-Gerasimenko. This allowed us to determine two regionsof high spectral activity using the two probes of the LAP instrument and to proposeseveral theories about the physical processes that were active.