Description: The term heliocentric is from the Greek helios, which is the name for the Sun, and kentro meaning center. This model of the Solar System places the Sun at the center and the planets orbit around it, replacing the geocentric (Earth-centered) model. Although the origin of the model is attributed to Copernicus in the 16th century, Aristarchus of Samos developed a heliocentric model in Ancient Greece and astronomers in India, Europe, and the Islamic world discussed such models prior to Copernicus. Observational evidence for the heliocentric model came through the telescopic observations of Venus made by Galileo. The original heliocentric model placed the Sun at the geometric center of the Solar System; this view changed with the mathematical formulations of Kepler using Tycho Brahe’s data, which Newton built on and expanded with his law of gravitation.

Related Terms:

• Geocentric Model

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

The OAE Multilingual Glossary is a project of the IAU Office of Astronomy for Education (OAE) in collaboration with the IAU Office of Astronomy Outreach (OAO). The terms and definitions were chosen, written and reviewed by a collective effort from the OAE, the OAE Centers and Nodes, the OAE National Astronomy Education Coordinators (NAECs) and other volunteers. You can find a full list of credits here. All glossary terms and their definitions are released under a Creative Commons CC BY-4.0 license and should be credited to "IAU OAE".