A total solar eclipse is when the moon completely covers the sun, casting a shadow that brings temporary darkness on Earth. It only occurs along what's called the path of totality, and the last time this path landed in the United States was 1979.
Only a few states experienced totality that year, but a majority of the surrounding states still experienced a partial eclipse. Seeing this state of totality is such a rare occurrence that some consider it a once-in-a-lifetime experience.
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