The geocentric model of the solar system worked pretty well for quite a long time. People believed it because it seemed to explain the observed world.
Looking up at the night sky, things seem to go around us — the sun, the moon, stars, and planets. It’s easy for us, with the benefit of millennia of thought and careful observation from others, to chuckle at the silliness of a solar system with the earth at its center.
Truth is, without the benefit of other people’s work on this issue, if you or I looked up at the night sky every night of our lifetimes, we’d be lucky to come up with a model as good as Ptolemy’s.
Ptolemy and his contemporaries were not dummies, and as observation of the apparent motion of celestial bodies improved, it became clear there were some subtleties that a simple “rings around the earth” model couldn’t explain.
Epicycles were a clever way to make the geocentric model of the solar system better match observations. Trouble was, more and more epicycles had to keep being added to account for more and more precise observations.
Things got pretty complex:
Along came Galileo, and the rest is history. The heliocentric model of the solar system is so much more elegant than the hairy epicycles of Ptolemy. While elegance doesn’t…