1509 in science

The year 1509 in science and technology included many events, some of which are listed here.

Exploration

 * September 11 – Diogo Lopes de Sequeira reaches Malacca, having crossed the Gulf of Bengal.

Geology

 * September 10 – Constantinople earthquake.

Mathematics

 * June 11 – Luca Pacioli's De divina proportione, concerning the golden ratio, is published in Venice, with illustrations by Leonardo da Vinci.

Births

 * Bernardino Telesio, Italian philosopher and natural scientist (died 1588)
 * possible date – Guillaume Le Testu, French privateer, explorer and cartographer (k. 1573)

Deaths

 * Juan de la Cosa, Spanish explorer and cartographer (b. c. 1460)