Occultation by Europa on 2017 March 31. The centre of the body at the time of closest approach between the shadow and the geocentre (CA), at 06:44:36 UTC, is represented by the large red dot. Blue lines represent the size limit of Europa (1561.2 ± 3.6 km). The small red dots represent the centre of the body, each separated by 1 min from the reference instant CA. The blue dots are the observers with positive detection, and the yellow dots are observers that were unable to obtain the light curve due to bad weather conditions. The offset between our result and the prediction (using the JPL jup310 ephemeris) was −0.90 ± 3.1 km for f_c and −12.3 ± 2.0 km for g_c, see Sect. 3. The black arrow at the bottom represents the direction of motion of the shadow.