Al-Zarqali leads the compilation of the Toledan Tables (~1080), the most precise set of astronomical ephemerides in Europe until the 13th century, based on 25 years of systematic observations in Toledo. He corrects Ptolemy's length of the Mediterranean from 62° to ~42° (the correct value). He invents the saphaea, the first universal astrolabe independent of the observer's latitude, used by navigators until the 16th century. He demonstrates the motion of the solar apogee relative to the fixed stars, calculating its value at 12.04 arcseconds per year (modern value: 11.8″). The Tables were translated into Latin by Gerard of Cremona c. 1175 and used directly by Copernicus.