1603 in science

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The year 1603 in science and technology involved some significant events.

Astronomy

Johann Bayer publishes the star atlas Uranometria, the first to cover the entire celestial sphere,^[1] and introducing a new system of star designation which becomes known as the Bayer designation.
Dutch explorer Frederick de Houtman publishes his observations of the southern hemisphere constellations.^[2]

Girolamo Fabrici studies leg veins and notices that they have valves which only allow blood to flow toward the heart.

August 17 – Accademia dei Lincei, the oldest scientific academy in the world, is founded in Rome by Federico Cesi.