Description: This principle in its original form is an outcome of the Copernican model for the Solar System. This "heliocentric" model stated the planets orbit the Sun and replaced the previously held belief that the Earth was in a special place in the center of the Solar System. Philosophically, the Copernican Principle represents a fundamental shift in the human perception of our place in the Universe. This shift was revolutionary in the time of Copernicus. The Copernican Principle has been extended to cosmology where it is called the Cosmological Principle, which provides one of the key foundations of modern cosmology – there is no special location or direction within the observable Universe. Both principles are constantly being tested through a range of observations at various scales, using ground and space-based telescopes.

Related Terms:

• Copernican Revolution
• Cosmological Principle
• Cosmos
• Geocentric Model
• Heliocentric Model

Term and definition status: This term and its definition have been approved by a research astronomer and a teacher

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