A mutual occultation of two iovian moons occurred ob Feb. 12, 2015: Io (the innermost of the Galilean satellites) occulted Ganymede, the largest of all moons in the solar system. Colleagues Hans Kirch and Georg Görgen had a 12" Newtonian and a ASI 120MM video camera equipped with a Planet Pro IR-pass filter at their disposal to record the event.
Despite poor seeing conditions, they managed to image the passing of Io and its shadow before Ganymede.
Video footage used with permission. Credit: Hans Kirch/Georg Görgen (www.monschauer-sternfreunde.de)