Figure 23: Observed Lightcurve of a microlensing event towards the bulge of the galaxy, event OGLE #6 [188]: The I-band magnitude is plotted as a function of time (Julian days). In the top panel, the constant V-I color of the star is shown. The maximum magnification is  = 6.9 (or 2.1 mag), the duration of the event is 8.4 days. The star has constant brightness in the following year (Credits: Andrzej Udalski.)