The Birth of Modern Astronomy

Read about the revolutionary shift to heliocentric cosmology in 2.4 The Birth of Modern Astronomy.
Watch the teacher video Ptolemy and Copernicus, which compares and contrasts the Ptolemaic and Copernican models of our solar system. If you’d like to experiment with the simulations used in this video, you can find them here: heliocentric model, retrograde motion, epicycles demo.
One argument in favor of the heliocentric model of our solar system is that it is more elegant and simple than a geocentric model. This is beautifully illustrated with this side-by-side comparison.
One argument against the heliocentric model is that it is totally insane! I mean, clearly the earth is fixed and the sun moves around it - just look up at the sky! Overcoming this popular view was extremely difficult and arguably represents the first great achievement of modern science. Credit for this achievement is often given to Galileo. Watch the brief video, Galileo - Physicist, to learn about his many contributions to modern science.
Watch the excellent PBS clip Galileo: Sun-Centered System, which shows how Galileo got the idea to examine the Phases of Venus, and what those observations led him to conclude.
It can be difficult to visualize how the phases of venus prove that the sun is at the center of our solar system. Check out the video Phases of Venus to walk through a simulation of how this works. You can also play with the simulations for yourself: Ptolemaic Phases of Venus, Heliocentric Phases of Venus.
Perhaps you’ve already noticed that there is a strong Eurocentric and male-dominated bias in our discussion of the history of astronomy. Unfortunately, this bias is real and it continues to today. We should acknowledge that the study of the night sky was universal among all peoples and cultures, as evidenced by archeological sites around the world that are aligned to the sun, moon, and stars. Watch the video Astronomy is Universal to see what I mean.
The scientific community, globally, tends to acknowledge its failures of the past, even as it continues to perpetuate systems that inhibit women and people of color from pursuing careers in science.