Galileo Galilei is the prominent figure known for his innovative work in the field of astronomy. Often referred to as the "father of modern observational astronomy," Galileo made significant discoveries, including the four largest moons of Jupiter, detailed observations of Venus, and extensive studies of planetary motion. His use of the telescope revolutionized the understanding of the solar system and supported the heliocentric model proposed by Copernicus. Galileo's challenges to established scientific views laid the groundwork for modern physics and astronomy, marking a pivotal moment in the shift toward empirical science.