  When a fast dust particle hits a spacecraft, it generates a cloud of plasma
some of which escapes into space and the momentary charge imbalance perturbs
the spacecraft voltage with respect to the plasma. Electrons race ahead of
ions, however both respond to the DC electric field of the spacecraft. If the
spacecraft potential is positive with respect to the plasma, it should attract
the dust cloud electrons and repel the ions, and vice versa. Here we use
measurements of impulsive voltage signals from dust impacts on the Parker Solar
Probe (PSP) spacecraft to show that the peak voltage amplitude is clearly
related to the spacecraft floating potential, consistent with theoretical
models and laboratory measurements. In addition, we examine some timescales
associated with the voltage waveforms and compare to the timescales of
spacecraft charging physics.
