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How did Copernicusā€™s heliocentric model explain the order of the planets?

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Nicolaus Copernicus
Nicolaus Copernicus Portrait of Nicolaus Copernicus, 1580, from the Town Hall in Toruń, Poland; in the collection of Muzeum Okręgowe w Toruniu (Regional Museum in Toruń). In his book De revolutionibus, he proposed that the Sun was the center of the solar system and that the planets circle the Sun.

Nicolaus Copernicusā€™s heliocentric model resolved long-standing debates regarding the arrangement of the heavens by placing the Sun at the center of the solar system.12

In the Ptolemaic system, astronomers disagreed on the order of the planets, particularly the positions of Mercury and Venus relative to the Sun. Copernicus demonstrated that by assuming the Sun is the fixed point of reference and that Earth is a planet in motion, the remaining planets fall into a logical, orderly relationship based on their sidereal periods.32

Under this system, the planets are ordered by the time they take to orbit the Sun, with their periods increasing as their distance from the Sun increases:
* Mercury (88 days)
* Venus (225 days)
* Earth (1 year)
* Mars (1.9 years)
* Jupiter (12 years)
* Saturn (30 years)3

This arrangement provided a singular, unified method for determining the relative distances of the planets, replacing the disjointed models of his predecessors with an orderly, cohesive system.3