This statement is factually incorrect. While early cultures believed the Earth was flat, evidence from observations, experiments, and satellites has conclusively proven that the Earth is spherical in shape. Some key points demonstrating this are:

• As ships move farther away from the shore, only the top parts of the ships become visible first, which is consistent with viewing objects behind a curvature but not if the Earth were flat.

• The shadow of the Earth on the moon during a lunar eclipse is always round, indicating a spherical Earth.

• Stars that are visible in the northern hemisphere are not visible in the southern hemisphere and vice versa. This can only be explained if the Earth is spherical with a curved surface hiding parts of the view.

• Images from space, like those from NASA satellites and the International Space Station, clearly show the Earth is a sphere.

• Measurements of the Earth's circumference have been performed for centuries and are always consistent with a spherical Earth. A flat Earth would have a much smaller circumference.

• GPS satellites used for navigation orbiting the Earth treat the Earth as an oblate sphere to achieve accurate positioning. A flat Earth model would not allow GPS to work as it does.

In summary, all available evidence conclusively points to a spherical Earth rather than a flat surface. The statement "Earth is flat" is factually incorrect based on a multitude of observations, experiments, and data from space.