Johannes Kepler did. In perhaps the greatest demonstration of empirical discovery,
he took Tycho's data ... compiled over a lifetime of observing and reporting where
the planets appeared in the night sky ... and deduced three simple statements that
described a system of planetary motion that could produce those appearances.
Kepler didn't say why the planets should behave that way and, technically, he didn't
even say that they do behave that way. He merely said: Here's a system to describe
the motion of the planets, and by the way, it fits what we actually see the planets
doing in the sky over periods of many years, and it's simpler than any other system
that's ever been offered, so there may be a good chance that it's true.
Almost 100 years later, Isaac newton was writing his own hypotheses, theories,
and conjectures, including his 'laws' of motion and his 'law' of gravity. He was able
to show that IF his laws of motion and gravity are correct, then one result would be
that moons and planets MUST behave according to Kepler's laws.
Johannes Kepler
Kepler
Johannes kelper
The main difference was that Ptolemy's model was geocentric (Earth-centred) and Copernicus's was heliocentric (Sun-centred). Ptolemy's model came from ancient times while Copernicus's was much later (1543). Both models represented the planets' orbits by using combinations of circles and epicycles to explain the way the planets move among the stars. Copernicus found that the orbits of the inner planets could be explained more simply. That is to say that the epicycles used for all the orbits were smaller, and for the inner planets a lot smaller. Both models represented the planets' positions with reasonable accuracy given the crude observational methods used in those days. Until gravity and the laws of dynamics were discovered about 150 years after the publication of Copernicus's system, there was no way of deciding which model was the 'right' one.
Isaac Newton
Nicolaus Copernicus
It was Ptolemy's model. Ptolemy's model came from ancient times while Copernicus's was much later (1543).Both models represented the planets' orbits by using combinations of circles and epicycles to explain the way the planets move among the stars.Copernicus found that the orbits of the inner planets could be explained more simply. That is to say that the epicycles used for all the orbits were smaller, and for the inner planets a lot smaller.Both models represented the planets' positions with reasonable accuracy given the crude observational methods used in those days.Until gravity and the laws of dynamics were discovered about 150 years after the publication of Copernicus's system, there was no way of deciding which model was the 'right' one.
Johannes kelper
Nicolaus Copernicus.
Copernicus was the first astronomer to come up with the idea of heliocentric cosmology (planets orbit the sun).
Copernicus
Copernicus.
The main difference was that Ptolemy's model was geocentric (Earth-centred) and Copernicus's was heliocentric (Sun-centred). Ptolemy's model came from ancient times while Copernicus's was much later (1543). Both models represented the planets' orbits by using combinations of circles and epicycles to explain the way the planets move among the stars. Copernicus found that the orbits of the inner planets could be explained more simply. That is to say that the epicycles used for all the orbits were smaller, and for the inner planets a lot smaller. Both models represented the planets' positions with reasonable accuracy given the crude observational methods used in those days. Until gravity and the laws of dynamics were discovered about 150 years after the publication of Copernicus's system, there was no way of deciding which model was the 'right' one.
Isaac Newton
Copernicus
Why the planets stayed int their orbit.
Nicolas Copernicus
His theory of the planets came out in 1543.
It was Copernicus.