Which scientist is associated with presenting a sun-centered model of the solar system?

• A. Ptolemy
• B. Copernicus
• C. Galileo
• D. Brahe

Answer: (B)

The concept being tested is heliocentrism—the idea that the Sun is at the center of the solar system and the planets, including Earth, revolve around it. Copernicus is the figure who first presented a formal sun-centered model during the Renaissance, arguing against the long-standing geocentric view associated with Ptolemy and proposing that Earth itself orbits the Sun. This shift laid the groundwork for modern astronomy and influenced later astronomers who provided supporting evidence. Ptolemy, by contrast, defended a geocentric system with Earth at the center and complex epicycles to explain planetary motion. Brahe contributed precise observational data and proposed an alternative geo-heliocentric arrangement, but he did not advocate a fully sun-centered model. Galileo later offered strong observational support for heliocentrism, yet the initial presentation of the sun-centered model is attributed to Copernicus.