Danish nobleman Tyco Brahe (1546-1601) was the greatest astronomer of his time, taking the most accurate measurements of the orbits of planets and the moon with scientific instruments of his own design. The telescope was not invented until seven years after his death. Above, his "armillae aequatoria maximae" (or, "great equatorial armillary") used for measuring the paths of planets and the moon across the sky, as found in Johan Blaeu's Le grand atlas ou cosmographie Blaviane, published in 1663. Blaeu's work was comprised of 12 volumes, totaling some 3,000 pages of text and nearly 600 double-page maps. Blaeu's hand-colored depictions of Brahe's instruments are based on Brahe's own wood-cuts, first published in his Astronomiae Instauratiae Mechanicae from 1598.

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Image: Booktryst.