One-Year Analysis of Dust Impact-Like Events Onto the MMS Spacecraft

We present an analysis of 1-year data of dust impacts observed on two of the Earth-orbiting Magnetospheric Multiscale mission (MMS) spacecraft. The dust impact signals were identified in observations of the electric field probes and were registered simultaneously by monopole and dipole configurations of the instrument. This unique setup allows us to reliably identify changes in the spacecraft potential as candidates for dust impacts. We present a detailed study of the properties of the pulses generated by the dust impacts and show the influence of the local plasma environment (spacecraft location in the Earth magnetosphere) on signals generated by dust impacts and their detection. We discuss the credibility of impact identification and possible sources of signal misinterpretation. We find a total of 784 observed events that we can interpret as dust impacts and that we use to derive a dust flux. We show that MMS1 registered 0.7 and MMS3 0.8 dust impact-like events per hour. This corresponds to dust flux of 2.5-6 x 10(-5) m(-2) s(-1).