The circular shape of the Earth's shadow on the Moon during a lunar eclipse suggested to the Greeks that the Earth was
A) cylindrical in shape
B) at the center of the Universe
C) flat
D) spherical in shape

Question

Quizplus · Accepted Answer

The circular shape of the Earth's shadow on the Moon during a lunar eclipse can only be explained if the Earth is spherical in shape. If the Earth were flat, the shadow would be rectangular and if it were cylindrical, the shadow would have a distinctive curved shape. The Greeks were among the first to observe this phenomenon and concluded that the Earth was spherical in shape based on this observation.

The Circular Shape of the Earth's Shadow on the Moon