The Birthday of Tycho Brahe (1546) – Naked Eye Astronomy

Tycho Brahe made the most accurate pre‑telescopic observations. He used geometry to measure planetary positions to 1 arcminute. His data allowed Kepler to derive laws of planetary motion. Tycho lost his nose in a duel and wore a metal prosthetic. He built an observatory (Uraniborg) with large quadrants and sextants – instruments that use the mathematics of angles. Tycho’s model (geocentric but with planets orbiting Sun) was wrong, but his data were right. Precision measurement is the foundation of science.