1596 in science

The year 1596 in science and technology included some significant events.

Astronomy

 * David Fabricius discovers the first non-supernova variable star, Omicron Ceti.
 * Johannes Kepler's Mysterium Cosmographicum is the first published defense of the Copernican (heliocentric) system of planetary motion.

Botany

 * Gaspard Bauhin publishes Pinax theatri botanici, an early classified flora.

Mathematics

 * Ludolph van Ceulen computes π to twenty decimal places using inscribed and circumscribed polygons.

Medicine

 * William Slingsby discovers that water from the Tewitt Well mineral spring at Harrogate in North Yorkshire, England, possesses similar properties to that from Spa, Belgium.
 * Li Shizhen's Compendium of Materia Medica (Bencao Gangmu) is published posthumously in an illustrated edition.

Earth sciences

 * Abraham Ortelius, in the last edition of his Thesaurus geographicus, considers the possibility of continental drift.

Exploration

 * June 17 – Willem Barents makes the first documented discovery of Spitsbergen in the Svalbard archipelago.

Technology

 * John Harington describes the "Ajax", a precursor to the modern flush toilet, in The Metamorphosis of Ajax.

Births

 * March 31 – René Descartes (d. 1650), French-born philosopher and mathematician.
 * approximate date – Peter Mundy (d. c.1667), English traveller.

Deaths

 * January 27 – Sir Francis Drake (b. 1540), English explorer (at sea).
 * September 15 – Leonhard Rauwolf (b. either 1535 or 1540), German botanist and physician.
 * September – Pieter Dirkszoon Keyser (b. 1540?), Frisian navigator (at sea).