Galileo Galilei's scientific pursuits challenged societal norms by undermining the prevailing geocentric model of the universe. Through his use of the telescope, he made groundbreaking astronomical discoveries, such as the moons of Jupiter and the phases of Venus, supporting the heliocentric theory proposed by Copernicus. Galileo's advocacy for a scientific approach based on observation and experimentation clashed with established religious beliefs, leading to conflicts with the Catholic Church. His willingness to defy authority for the sake of truth laid the groundwork for modern scientific inquiry and emphasized the importance of empirical evidence in understanding our world.