Polarisation as observed in four wavelengths near Skibotn, Norway on March 7, 2019. Petit Cru is at 164° in azimuth and 45° in elevation. Several filters were used to observe the red (top left), green (top right), blue (bottom left) and purple (bottom right) lines. In black are shown the raw data along with the associated error bars in grey. The color lines (red, green, blue, purple) show the corresponding observed wavelengths smoothed over 15 s and their error bars in the same color. For all 4 wavelengths are given (from top to bottom) the observed intensity (in mV), the DoLP (in %) and the AoLP (in degrees). The intensity can not be compared between two different colors (due to different filters). When available, electron density at the point of emission is shown in yellow on top of the intensity. The rate of change of the horizontal component of the magnetic field in Tromsø is given in yellow on top of the DoLP. We also show, superimposed with the AoLP, the apparent angle of the magnetic field lines (in cyan) and the expected AoLP for scattered light for a artificial source point in Skibotn (in pink).