Aristotle philosophized that heavier objects should fall faster than light objects. Galileo hypothesized that all objects fall at the same rate.
Galileo had only water clocks and his eyes to work with. But he brilliantly proofed his case by rolling balls down inclines. (The dropping of balls from the tower of Pisa is fake news)
Today, we have vacuums and high speed cameras.
–
Apollo 15
https://nssdc.gsfc.nasa.gov/planetary/lunar/apollo_15_feather_drop.html
–
Brian Cox
–
Brainiac