Copernican system

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Copernican system,

first modern European theory of planetary motion that was heliocentric, i.e., that placed the sun motionless at the center of the solar system with all the planets, including the earth, revolving around it. CopernicusCopernicus, Nicholas
, Pol. Mikotaj Kopérnik, 1473–1543, Polish astronomer. After studying astronomy at the Univ. of Kraków, he spent a number of years in Italy studying various subjects, including medicine and canon law. He lectured c.
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 developed his theory in the early 16th cent. from a study of ancient astronomical records. He retained the ancient belief that the planets move in perfect circles and therefore, like PtolemyPtolemy
(Claudius Ptolemaeus), fl. 2d cent. A.D., celebrated Greco-Egyptian mathematician, astronomer, and geographer. He made his observations in Alexandria and was the last great astronomer of ancient times.
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, he was forced to utilize epicycles to explain deviations from uniform motion (see Ptolemaic systemPtolemaic system
, historically the most influential of the geocentric cosmological theories, i.e., theories that placed the earth motionless at the center of the universe with all celestial bodies revolving around it (see cosmology).
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). Thus, the Copernican system was technically only a slight improvement over the Ptolemaic system. However, making the solar system heliocentric removed the largest epicycle and explained retrograde motion in a natural way. By liberating astronomy from a geocentric viewpoint, Copernicus paved the way for Kepler's lawsKepler's laws,
three mathematical statements formulated by the German astronomer Johannes Kepler that accurately describe the revolutions of the planets around the sun. Kepler's laws opened the way for the development of celestial mechanics, i.e.
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 of planetary motion and NewtonNewton, Sir Isaac,
1642–1727, English mathematician and natural philosopher (physicist), who is considered by many the greatest scientist that ever lived. Early Life and Work
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's embracing theory of universal gravitationgravitation,
the attractive force existing between any two particles of matter. The Law of Universal Gravitation

Since the gravitational force is experienced by all matter in the universe, from the largest galaxies down to the smallest particles, it is often called
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, which describes the force that holds the planets in their orbits.


See E. Rosen, Copernicus and His Successors (1995); T. S. Kuhn, The Copernican Revolution (1997).

Copernican system

(kŏ-per -nă-kăn) A heliocentric system of the Solar System that was proposed by Nicolaus Copernicus and eventually published in 1543 in his book De Revolutionibus . It uses some of the basic ideas of the Ptolemaic system, including circular orbits and epicycles, and was no more accurate in its predictions. Copernicus, however, maintained that the planets move around the Sun (in the relative positions accepted today), the Sun's position being offset from the center of the orbits. The apparent motions of celestial bodies such as the Sun were explained in terms of the rotation of the Earth about its axis and also the Earth's orbital motion.

The planetary motion can be represented by two uniform circular motions: one is an epicyclic motion of the planet about a point D on the circular orbit; the other, unlike that of the Ptolemaic system, is a uniform circular motion of D about the center, C, of the orbit. This requires that the rate of motion of D about C is exactly half that of the epicyclic rate of motion with respect to a fixed direction.

There was a strong and prolonged reaction – especially by the Church – to the Copernican system, which effectively displaced the Earth as the center of the Universe. There was also a sudden revival in astronomical observation in order to test the theory, notably by Tycho Brahe. Tycho's detailed observations, which showed the inadequacies of the Copernican system, were used in the formulation of Kepler's laws of planetary motion. The heliocentric cosmology became firmly established after Galileo had made telescopic observations of the phases of Venus.

Copernican System

(kŏ-per -nă-kăn) The youngest stratigraphic system of the Moon. It includes the freshest lunar craters, formed during the last billion (109) years approximately, many of which have preserved rays. The period began with the formation of the crater Copernicus. The Eratosthenian System (for which Eratosthenes is the type crater) covers the earlier period extending from about 3.15 to 1 billion years ago. It includes slightly older more degraded craters with no visible rays, in addition to most of the youngest mare deposits. See also Imbrian System; Nectarian System.

Copernican system

[kə′pər·nə·kən ‚sis·təm]
The system of planetary motions according to Copernicus, who maintained that the earth revolves about an axis once every day and revolves around the sun once every year while the other planets also move in orbits centered near the sun.
References in periodicals archive ?
The great Danish astronomer Tycho Brahe (1546-1601), the finest and most prolific observer prior to the invention of the telescope, objected to the Copernican theory for this reason.
The two met six times over the course of six weeks in 1624, discussing the "hypothetical" Copernican theory without any conflict.
In a recent unpublished paper, Silvia Manzo argues that Hume endorses the Copernican theory because it is simple, beautiful, and uniform (14).
He wrote the first published discussion of Copernican theory, and was instrumental in the publication of Copernicus's pivotal De revolutionibus orbium coelestium (On the Revolutions of the Heavenly eres).
He rehabilitated the honor of Galileo, who was tried by the Inquisition for his Copernican theory in opposition to the Church, and recognized Darwin's theory of evolution as more than hypothetical theory.
We are in the position of medieval astronomers who fear that if the Copernican theory of the solar system is true, "the earth" as we have conceived it does not exist.
Galileo supported the Copernican Theory that, rather than the sun going around the Earth, the appearance of solar movement was caused by the rotation of the Earth.
The Copernican theory, he held, is validated by its ability, through the Earth's motion, to provide a unified system, and to remove the ambiguity in the order of the innermost planets and the Sun.
Elmendorf in November 2001, entitled "Rings Around the Sun--or Not," challenging the Copernican theory of heavenly motions.
Earlier challenges to religion came from the Copernican theory of the solar system and from naturalist Charles Darwin's theory of evolution.
As it stands, the book is primarily about the father's exploration and acceptance of the Copernican theory of the universe, his difficulties with Church politics, and only tangentially his relationship with his daughter.
Yet, Bruno's vision of an infinite universe, with which he complemented and helped generate acceptance for the Copernican theory, was derived largely from the ancient materialists Epicurus and Lucretius, via the latter's De rerum natura.