Gnomon Projections
Hyperbolas / Analemmas SHADOWSAustria, 1997-1998The infinite shadow at daybreak projected by the gnomon, points west.In due time, the motion of the universe becomes traceable through the movement of the shadow along its pathtowards the east. There are two different motions reflected in the square. The first, the speed of the Earth in its orbitaround the Sun, is drawn by the shadow of the gnomon on the white marble sand. The second is the atmosphericmovement mirrored in theblack water basin during the day.The forces of nature interacting with the sculptural elements are random, though the shadow is predestined.Connecting the positions for the same time each day, the shadow draws a Figure “8” or Analemma, while the pathofthe tip of the shadow for a single day is a Hyperbola. The exact shape of the Analemma depends on the time ofday. The eccentricity of the hyperbola depends on the date. The shapes of both also depend upon the latitude andlongitude of the location.The four sides of the square are 15 meters long and are aligned with the four cardinal points of the compass. Thevertical gnomon points to two additional directions: upwards, and via the water reflection, downward. The height ofthe gnomon is 6.91 meters. The site-specific installation with its latitude of 47 degrees north, and longitude of 15degrees east makes the length of the shadow at high noon definite.At the autumnal equinox, when the Sun is above the Equator, the shadow will travel along the northern edge of themarble basin. At high noon the shadow will be exactly 7.5 meters long, equivalent to the width of the marble basin.The shadow cast by the gnomon is at a 90-degree angle to the axis. It points north to the sideline of the square,which is the visual Hyperbola of that day.
