Many classical Greek astronomers believed the Earth could not move because they detected no parallax.

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Parallax is the apparent shift of the position of an object when viewed from different angles. Ancient Greek astronomers did not have the technology to detect the small parallax that occurs with distant stars, so they believed that the Earth was stationary at the center of the universe. This idea was eventually challenged by scientists like Copernicus and Galileo who proposed that the Earth and other planets actually orbited around the Sun.

Many Classical Greek Astronomers Believed the Earth Could Not Move