fl. c. 490 B.C.

Babylonian astronomer credited with devising what came to be known as System A, a set of tables accounting for the positions of the Sun, Moon, and planets at any particular time. As a result of inaccuracies in this system, Kiddinu (fl. c. 350 B.C.) would later correct the earlier method with what historians refer to as System B. Nabu-rimanni calculated the synodic month (i.e., from new Moon to new Moon) as 29.530614 days, a figure that according to modern calculations was correct to the third decimal place.