How did early astronomer's learn the true order of our solar system. Long before telescopes and even science was available, numerous astronomers made discoveries which eventually led to our understanding.
Early Astronomers made discoveries that led to the current understanding of the Solar System.
Ptolemy put the Earth at the center of the Solar System
Copernicus put the Sun at the center of the Solar System
Tycho Brahe took accurate measurements of the Planets
Kepler discovered the shape that the planets and all other objects orbit
Galileo was the first to turn a telescope to the skies and observe moons around Jupiter
Isaac Newton discovered the one property that holds the Solar System together, and was able to prove it.