Overview of Solar Orbiter V_sc. (a) Evolution of the spacecraft potential determined from Eq. (14). The yellow line depicts the smoothed V_sc showing its average trend. Similarly, the solid blue line represents the smoothed spacecraft-to-probe potential −V_ps = V_sp. (b) Percentage of data points within a month where V_sc ≥ 0 V. The right axis shows Solar Orbiter’s heliocentric distance in au. Most of the time the potential is positive, but there are moments where it becomes negative. The green vertical lines mark the times of the discrete events related to the solar array fuses. (c) Histogram of V_sc with heliocentric distance.