Heliocentrizmus

Heliocentrizmus is the astronomical model that places the Sun near the center of the solar system, with the planets, including Earth, orbiting it. In this view, the apparent motions of the stars and planets are explained by the orbital dynamics around a central Sun rather than by a fixed Earth at the center.

Historically, Aristarchus of Samos proposed a heliocentric system in antiquity, but his ideas had little influence at the time. In the 16th century Nicolaus Copernicus revived heliocentrism and published De revolutionibus orbium coelestium (1543), arguing that the Sun, not the Earth, occupied the central position. The model offered a simpler explanation for the retrograde motion of planets and for variations in their brightness.

Empirical support came from later observations and theory. Galileo Galilei’s telescopic discoveries, such as the phases of Venus and the moons of Jupiter, challenged geocentric models and supported a Sun-centered system. Johannes Kepler refined the model with his laws of planetary motion, describing elliptical orbits. Isaac Newton’s law of gravitation provided the physical basis, showing how a central body can govern the orbital motions of others.

In modern astronomy, the heliocentric model is the accepted description of the solar system: the planets orbit the Sun due to gravitation. The system revolves around a solar system barycenter, which is generally located near or inside the Sun. Heliocentrism distinguishes the Sun-centered arrangement of the solar system from geocentrism and underpins celestial mechanics and the broader understanding of planetary motion.