A total solar eclipse occurs when the dark silhouette of the moon completely obscures the intensely bright light of the sun, allowing the much fainter solar corona to be visible. During any one eclipse, totality occurs at best only in a narrow track on the surface of Earth. This narrow track is called the path of totality.

If the Moon were in a perfectly circular orbit, a little closer to the earth, and in the same orbital plane, there would be total solar eclipses every new moon. However, since the moon's orbit is tilted at more than 5 degrees to the earth's orbit around the Sun, the shadow usually misses the Earth.

A solar eclipse can only occur when the Moon is close enough to the ecliptic plane during a new moon. An eclipse is a natural phenomenon. However, in some ancient and modern cultures, solar eclipses were attributed to supernatural causes or regarded as bad omens.

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