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#1: Watch a Lunar Eclipse

Solar and Lunar Eclipses Worldwide – 2023

A lunar eclipse occurs when the Earth is directly between the sun and the moon. This positioning causes the Earth to cast a shadow onto the moon. In a total lunar eclipse the Earth’s shadow completely covers the moon. This shadow darkens the moon’s surface.

The shape of the Earth’s shadow on the moon during lunar eclipses is always spherical. This is because the Earth is round and a round object casts a round shadow. Try it with a dark room, a flashlight, and an orange or a ball. You will have a tough time getting a non-spherical shadow out of the ball.

Now try the same activity with a dinner plate. You will notice that it is much easier to make shadows that are shapes other than round. If the Earth were flat and shaped like the dinner plate, the Earth’s shadow during a lunar eclipse would often be one of these non-round shapes. It could be oval or even just a thick line. This has never happened.