Galileo Galilei (1564 to 1642) is recognized as the father of science. He discovered the pendulum as a means to accurately measure time. He discovered a thermoscope (forerunner of the thermometer) and a hydrostatic balance. He reasoned that the speed with which a body falls due to the acceleration of gravity does not depend on the mass of the body. He also worked with an inclined plane – regardless of the weight of the ball (soft wood, hard wood, or stone), the balls rolled down the inclined plane at the same rate of acceleration. He discovered that the density of lead was twelve times the density of water (it is actually 11.3 times as dense). Galileo made more and more powerful telescopes after they were invented in The Netherlands. He sold telescopes as a side business, since he needed money to avoid debtors prison (his father died and his sister’s dowry had to be paid). Eventually, he made a telescope with 30X magnification and quality lenses. With this, he discovered the moons of Jupiter, the rings of Saturn (the “planet with ears”), and that the moon was not a perfect sphere but had mountains and valleys.
There is a special exhibit on Galileo Galilei in the church of Santa Maria degli Angeli e Martyri in Rome. This church was built from the ruins of Diocletian’s Baths in 1566 under the direction of Michelangelo. This church also contains the Meridiana which was used to accurately tell time between 1702 and 1870 (see “007 Meridiana”, below). The exhibit in the church describes some of Galilei’s discoveries, how he viewed the Holy Bible and the Book of Nature as two complimentary narratives, his belief that God could have created any world but always chose simplicity, and some of his controversies. Controversies filled his life, probably because he had a forceful character (he got in peoples’ faces). With his telescope, he could see that the Copernican movement of the planets was more correct than sun and stars rotating about the earth. Galileo wanted the church to stay out of the scientific debate. There were officials who supported his views and advice. There were other officials who Galileo had previously alienated.
David Scott, Commander of the Apollo 15 Mission, while he was standing on the surface of the moon, dropped a feather and a hammer at the same time. They fell to the surface at the same rate. “Galilei was right!” he exclaimed. With no atmosphere, there was no friction to slow the feather. Commander Scott conducted this experiment on his third Extra Vehicular Activity period on August 2, 1971. In the hallway leading to the Sacristy in Santa Maria degli Angeli e Martyri, there are some additional Galileo exhibits. A television monitor continuously replays the footage of Commander Scott’s experiment.
Galilei taught us that the Book of Nature is available to everyone. However, in order to decipher it, we need to pose precise questions to its Author. The questions must be rigorously formulated and the answers linked to reproducible experimental results. No one should presume to know more than He who made the world.