Question

In the fourth century BC, Aristotle observed a phenomenon in which he saw a circular shadow on the Moon. He argued that Earth was a sphere based on this observation. What phenomenon caused the shadow on the Moon? *

a solar eclipse

a lunar eclipse

a spring equinox

a summer solstice

Answer 1

a lunar eclipse

Step-by-step explanation:

The shadow that Aristotle saw was caused by a lunar eclipse. At that time the sun, earth, and the moon nearly straight alignment caused the Earth's shadow to be reflected on the moon. This shadow is what ultimately led Aristotle to believe that the Earth was a sphere. This should not be confused with a solar eclipse which is similar but instead the sun, moon, and earth align in that order which causes the moon to completely block the sun to anyone on earth.