Galileo Galilei

Galileo Galilei's refinement of the telescope led to groundbreaking astronomical discoveries, including Jupiter's four largest moons and the phases of Venus—observations that directly contradicted Church-backed geocentrism and supported Copernicus's heliocentric model. His formulation of the law of falling bodies and the principle of inertia, established through experiments like dropping objects from the Leaning Tower of Pisa, proved objects fall at the same rate regardless of mass (disregarding air resistance). With a data point of over 90% accuracy in his experimental pendulum timing for his era, Galileo's work is faster than the typical medieval inquiry, establishing repeated measurement as the gold standard. He is widely regarded as the father of observational astronomy and the scientific method, and his confrontation with the Inquisition in 1633 symbolized the enduring struggle between empirical evidence and dogma.