Copernicus revived Aristarchus's suggestion of a Sun-centered solar system and described it mathematically. Which figure fits this description?

• A. Ptolemy
• B. Aristotle
• C. Hipparchus
• D. Copernicus

Answer: (D)

Recognizing who revived Aristarchus's heliocentric idea and put it into a precise mathematical description. Aristarchus proposed that the Sun is at the center, but his work didn’t get developed or widely adopted. Copernicus again proposed a Sun-centered solar system and, crucially, worked out the geometry and motions in a formal, mathematical way in his work De revolutionibus orbium coelestium. He showed that the planets, including Earth, orbit the Sun, which explained planetary motions in a straightforward framework and set the stage for modern astronomy. The other figures are associated with a geocentric view, where Earth sits at the center, so they don’t fit the description as well. Therefore, Copernicus is the figure that matches.