Pretty much everyone was wrong, but very few people had the brazenness to even suggest an answer outside of either one of those accepted ranges. This direction-reversal occurs for all the planets and is known as retrograde motion. Here, the retrograde motion of Mars from March to May, 2014, is illustrated, with prograde motion occurring both before and after. What was most brilliant about this suggestion is that it could explain this apparent retrograde motion of the planets without any epicycles. Like Copernicus, he could explain retrograde motion without resorting to epicycles.

Source: Forbes August 11, 2020 06:00 UTC