eROSITA light curve (0.2–10 keV) of A0538−66 of the first sky survey. Each point during the flares represents one scan. Outside of the flares, the 90% c.l. upper limit was obtained by binning the data within one day. The top horizontal axis shows the orbital phase, and phase zero corresponds to the periastron passage. The inset shows the position of the eROSITA flares (blue stars) and of the optical peaks (red squares) in the orbit.