Computed light curve of the fireball from 19 May 2018 with applied fit. The x-axis displays the relative velocity v^* of the fireball for which each velocity value is divided by the fireball’s initial velocity. The brightness values, calculated as explained in Sect. 4.3 for each point in time for which a median magnitude value could be determined, are shown as a blue ‘×’. The applied fit is displayed as a solid red line.