Explain the shape of the Earth

A. Actual Shape of the Earth:

• The Earth is not a perfect sphere. It is an oblate spheroid:
  • Slightly flattened at the poles
  • Slightly bulged at the equator

Evidence That the Earth Is Spherical in Shape

• Photographs from space
  Satellites and astronauts have taken pictures showing the Earth as round.

• The shape of the horizon
  When a ship sails away, it disappears from the bottom up, not all at once, showing the curved surface.

• Earth’s shadow during a lunar eclipse
  The shadow cast by the Earth on the Moon is always round.

• Different time zones
  It is daytime in some parts of the world while it is night in others, which shows a round, rotating Earth.

• Airplane routes
  Planes follow curved paths called great circles, which are shortest on a spherical Earth.

• Variation in star visibility
  Different stars are seen in the sky from different places on Earth, due to its round shape.