Earth’s Rotation

350 BCE
- Heraclides Ponticus proposes that the Earth rotates once a day on its axis.
- The concept is not widely adopted because it contradicts Aristotle, who is regarded as more authoritative.
4th century BCE
- Aristotle claims that Earth is stationary in space.
950 CE
- Al-Siji, an Iranian astronomer supports the idea of the rotation of the Earth.
1543
- Nicolaus Copernicus states that Earth rotates as part of his heliocentric model of the cosmos.
1851
- The first demonstration of Léon Foucault's pendulum in Paris provides conclusive scientific evidence that the Earth rotates.

In the Western world, the idea that Earth is stationary and situated at the center of the universe predominated from the 4th century BCE to the 16 century CE.
Arguments that the Earth might be rotating were disregarded because doing so would send objects on Earth's surface hurling into space.
Aryabhata: An Indian astronomer believed that Earth's rotation was what caused the stars to move across the night sky.

According to Aryabhata, the stars were stationary, and their apparent movement westward was an illusion.
His concept of a spinning Earth was not widely accepted until the mid-17th century after Nicolaus Copernicus endorsed it.
It had a significant impact on Arabic astronomy and was essentially a compendium of the fundamentals of astronomy and pertinent mathematics.
Aryabhata also developed novel and precise methods for creating astronomical tables and calculated the sidereal day's length with a high degree of accuracy.
Sidereal Day: The period it takes for Earth to circle once around the stars.
Tychonic Model: A Tycho Brahe-created model of planetary motion in which the earth is still and in the center of the planetary system, the sun, moon, and other planets all circle around the earth.
Elliptical orbits: The movement of one celestial body around another in an oval-shaped path.