Here are some notes about the thousands of years of discoveries which have led to our present day understanding of the universe. We will briefly consider the seminal work of Thales of ancient Greece and end at the stunning changes in Astronomy in the seventeenth century.  Most of what we cover will deal with the planets.  Our understanding of stars was very rudimentary up until the mid-nineteenth century. We begin in the time of classical Greece, when the first attempts were made for a rational explanation of the sky.  Humans of that time, for the most part,  still believed in the central location of Earth.  For them, it was a geocentric universe.  In the time of the Renaissance, a Polish cleric by the name of Copernicus convinced himself that a simpler explanation had the Sun in the center of all things.  Following Copernicus was Galileo, who used the observational proof of his telescope to show the truth of the heliocentric theory.
Carpe Caelum Planetary Astronomy
Carpe Caelum Planetary Astronomy