Letters of the Greek alphabet glisten on a black background. When a letter appears, there is a sound. Each letter corresponds to a star in the sky. Alphas, betas, gammas spread in space. The sound attributed to the first letters is high-pitched, then it gets lower for the rest of the letters in alphabetical order. The composition is organised according to the order of magnitude which attributes a letter to every star in the constellation. A cartographic order is established : sequences of alphas, gammas, betas come to pass simultaneously. The positioning of the letters corresponds to that of the stars in the Northern Sky map, their appearance is guided by the distance compared to the previous star. The distance on the map is used as a given time : the closer a star is to the next one in space, the closer it is in space.