“All truths are easy to understand once they are discovered; the point is to discover them.” -Galileo Galilei
Galileo is most famous for his astronomical discoveries, including the moons of Jupiter, the existence of sunspots and the phases of Venus. These discoveries were a strong challenge to geocentrism, and his writings and debates helped popularize the heliocentric model.

Image credit: Wikimedia Commons user Fernando de Gorocica, under a c.c.a.-s.a.-3.0 license, of Galileo’s original (1610) sketches of the phases of Venus.
Yet, in a recent article for Aeon magazine, Thony Christie argues that Galileo’s contributions to astronomy were minimal compared to his contemporaries, and that he was not the transformative scientist he’s billed to be. While certainly Kepler and others made greater contributions to astronomy at the time, Galileo’s contributions to physics were unparalleled, as there was no greater giant whose shoulders Newton stood upon when he wrote his genre-defining works.
Go get the whole story on Galileo’s incomparable contributions to physics over on Forbes!