Columbus carried a rabbi's star tables — and an eclipse saved his stranded crew
Rabbi Avraham Zacuto wrote Sefer Yuchasin, a chronicle of the chain of Jewish tradition — and he was also Iberia's foremost astronomer, royal astronomer to the Portuguese crown. Columbus owned a copy of his almanac. In 1504, stranded on Jamaica after the islanders cut off his food, Columbus foretold a total lunar eclipse for the night of 29 February. The moon rose darkened, and the frightened islanders brought food. His own note on the eclipse says only “see the Almanach” — and historians still debate whether he meant Zacuto's tables or those of the German astronomer Regiomontanus.
How we know
Zacuto (1452–c. 1515): Sefer Yuchasin finished in Tunis, 1504; named royal astronomer in Portugal in a 1493 document; Chabás & Goldstein (Astronomy in the Iberian Peninsula: Abraham Zacut, APS 2000) call him pre-eminent among astronomers in Spain. His Almanach Perpetuum (Leiria, 1496) is listed among Columbus's books (Madariaga). Columbus beached his ships at Santa Gloria, Jamaica, in late June 1503; the eclipse fell on Thursday 29 February 1504 (Julian); rescue came in June 1504. Columbus's eclipse note (Libro de las profecías, transcribed in Kayserling 1894) ends “vide Almanach”; Ferdinand Columbus's Historie (1571) names no book. Morison (Admiral of the Ocean Sea, 1942) and other historians hold that he used Regiomontanus's Ephemerides; Kayserling read it as Zacuto's.
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