Aequatorial-Sonnenuhr

Aequatorial-Sonnenuhr stands on a green space west of Ignatz-Bubis-Brücke, beside the Main in Frankfurt’s Innenstadt. Its copper rings form an equatorial sundial and a world-time clock. A pole between the celestial poles casts the shadow across the equator, where the time display sits. The broad band carries twelve monthly scales, while Roman numerals show true local time.

Engineer and clockmaker Lothar M. Loske conceived the sculpture in the late 1940s. Vereinigte Deutsche Metallwerke built it over two years, using 6,000 hours of labour and 21,000 Deutsche Marks. Inaugurated in 1951, the structure originally stood at Untermainkai in Nizza park before Frankfurt received it as a gift. Restoration moved it 1.4 kilometres east in 2004, away from tree shade and planned restaurant construction.

The 3.6-metre sculpture weighs about 1,000 kilograms. Its support combines electroplated copper steel with the copper rings, because solid copper could not carry the weight. The narrower world-time ring lists 200 cities and rotates around the celestial axis. Set towards another city, it displays that place’s true local time or time zone, adjusted for the month.