Galileo

Galileo Galilei (1564–1642) was an Italian astronomer, physicist, engineer, and a central figure in the scientific revolution. Born in Pisa, he studied medicine before turning to mathematics and natural philosophy. With the support of patrons such as Cosimo II de’ Medici, he pursued astronomy with significant improvements to the telescope, enabling systematic celestial observations.

In 1610 he published Sidereus Nuncius (The Starry Messenger), describing mountains and craters on the Moon, the four largest satellites of Jupiter (Io, Europa, Ganymede, and Callisto), and the vast number of stars in the Milky Way. His observations provided important support for the Copernican heliocentric model, though he faced opposition from the Catholic Church. Galileo argued that celestial phenomena could be explained by natural laws and mathematics, challenging Aristotelian cosmology.

In addition to astronomy, Galileo conducted studies of motion and mechanics, advancing experimental methods and early concepts of inertia. His approach emphasized observation, measurement, and mathematical description as the path to knowledge.

His advocacy for heliocentrism led to formal proceedings by the Roman Inquisition in 1633, and he was found guilty of heresy, forced to recant, and spent the remainder of his life under house arrest. The Church’s stance softened over time, and in the late 20th century significant reconsideration acknowledged errors in the trial.

Galileo’s legacy rests on his insistence that empirical observation and quantitative reasoning are essential to understanding the natural world, shaping modern science and the method by which discoveries are pursued.