Question

Which of the following phenomena gives evidence for the spherical shape of the earth?
A) Solar eclipse
B) Lunar eclipse
C) Revolution
D) Rotation of Earth

Answer 1

Hint: The approximation of the Earth's figure as a sphere is known as spherical Earth or Earth's curvature. The concept appears in Greek philosophers' works in the 5th century BC, and it is the oldest documented mention of it. Hellenistic astronomy established the roughly spherical form of the Earth as a physical fact and determined its circumference in the 3rd century BC.

Complete answer:
When the Moon passes through the shadow of the Earth, a lunar eclipse occurs. This can only happen on the night of a full moon when the Sun, Earth, and Moon are precisely or extremely closely aligned, with Earth between the other two.

Let us look at the given options:
A) Solar eclipse: This option is incorrect because a solar eclipse happens when the Moon casts a shadow over a section of the Earth, blocking sunlight completely or partially. It provides no proof regarding the shape of the earth.
B) Lunar eclipse: This is the correct option. The Earth throws a round shadow on the moon's surface during a lunar eclipse, whether partial or total, and the sphere is the only shape that creates a round shadow no matter what the direction of light is.
C) Revolution: This option is incorrect because it provides no proof regarding the shape of the earth. Revolution is the movement of the earth around the sun in a fixed route or orbit.
D) Rotation of Earth: The movement of the earth on its axis is known as rotation. Seasonal changes, as well as day and night, are caused by the earth's rotation; it provides no proof regarding the shape of the earth. Hence, this option is incorrect.

The correct answer is Option (B) i.e, Lunar eclipse.

Note: The reddish tint of a completely eclipsed Moon, which is caused by Earth entirely obstructing direct sunlight from reaching the Moon, is frequently referred to as a blood moon. Earth's atmosphere has refracted the only light reflected from the lunar surface. The Rayleigh scattering of bluer light causes this light to seem reddish, much as it does at sunset or sunrise.