Each year, around the winter solstice, the Cathedral of Mallorca offers us the spectacle of a giant kaleidoscope of color. Light rays enter in a perfect way through the major rosette, the one of the altar, and out of the main door rosette, the western one, so that a colored cylinder is created. Viewed from the terraces of Sant Pere Baluard, it is one of the most beautiful sunrises that can be seen.
This geometric and scientific phenomenon has been studied by the Balearic Mathematics Society (SBM-Xeix). With the aim of disseminating mathematical knowledge, after observation of this effect a conference in Aljub Es Baluard under the title Holbein, los Cosmati, fractales y vitrales (Holbein, the Cosmati, fractals and stained glass). It will be given by professor Francisco Martín Casalderrey.
