1288-1344

French Jewish astronomer and mathematician who in his Sefer takunah (1340) attempted to replace the cosmology of Ptolemy with a new, rationalized Jewish cosmology. One of the few Jewish scholars to enjoy a successful career in Christian Europe, Levi observed a lunar eclipse in 1335 and a solar eclipse in 1337. He also developed the Jacob's staff, a mechanism for measuring the angular distance between heavenly bodies, and used the camera obscura in making astronomical observations.