Horizontal flow field in the runaway sunspot (relative to its centre). The arrows indicate the flow vectors derived from LCT, which have been overlaid on the LOS magnetogram. The thick black horizontal arrow at the bottom right corner corresponds to 1 km s^-1. The equidistant elliptical contours span an azimuth range of − 130° to 130°, which is scaled according to the vertical colour bar. A value of 0° azimuth coincides with the positive semi-major axis and increases in counter-clockwise direction. The plus corresponds to the centre of the sunspot.