The Renaissance (or "rebirth" in French) was a broad cultural awakening that included science and politics as well as art. Spain at the time was an exhilarating melting pot of Christian, Jewish and Muslim cultures. While Spain’s King Alfonse was commissioning new astronomical almanacs, schools of translators were rediscovering Aristotle and other Greek philosophers. They were also translating the work of Arab mathematicians, including Alhazen who invented the science of optics —the geometric study of how light travels and reflects. In the 15th century Italian artists used this new science to put depth into painting by the use of perspective. Perspective makes art come alive by giving it the sense of a third dimension. In much the same way the Greeks were able to use geometry to create an awareness of depth in space. Science and art were also united in turning to nature rather than established wisdom as the source of their inspiration. Leonardo da Vinci used the same ideas of optics to understand the shadowing of eclipses as he did to draw the shadows and contours of the human body. The Renaissance spread across Europe. Exciting new ideas are contagious!
The scientists of the Renaissance once again began to ask profound questions about the universe. How do we know that the Earth is the center of the Universe? What is the best way to understand the motions of the stars and planets? The Copernican revolution still influences our whole conception of the role of the human species in the cosmos, and even our religious and philosophical ideas. Also, it illustrates how science works. The whole modern idea of searching for other planets near other stars, or asking if there are alien civilizations, or picturing a starship "Enterprise" flying from world to world, comes from what we might call Copernican ideas, developed in the 1500s and 1600s. Before that, reasonable people thought that there was only one world in the whole universe — Earth, located at the center. To understand where we are today, we have to understand how the old idea was overthrown by the scientific method.
Portrait of?Galileo Galilei?by Justus Sustermans painted in 1636. National Maritime Museum, Greenwich, London. Click here for original source URL.
The astronomer Tycho Brahe. Click here for original source URL
A 1610 portrait of Johannes Kepler by an unknown artist. Click here for original source URL.
Sir Isaac Newton. Click herefor original source URL
By the 1500s, the best scientists had noted that older predictions of planetary positions were now in error by a degree or so. Spain’s King Alfonso X and others began to wonder if there might not be a simpler theory that could give better results than the patchwork Ptolemaic assembly of epicycles. One observer sought a new model that he said might be more "pleasing to the mind." This man was Nicolaus Copernicus, father of the Copernican revolution. The Copernican revolution took a century and a half, from roughly 1540 to 1690. It involved five very famous scientists: Copernicus, Tycho Brahe, Johannes Kepler, Galileo Galilei, and Isaac Newton.
Nicolaus Copernicus?portrait from Town Hall in Thorn/Toru??- 1580. Clickhere for original source URL