The last time a total eclipse could be seen from the US mainland was 1979, it will be seven years before the next one in April 2024

A solar eclipse occurs when the Sun, Moon and Earth align

A full shadow (umbra) traces a line across the surface of the Earth. In the 21 August event this shadow will be about 70 miles wide

A bigger penumbra (partial shadow) can be seen over a much greater area, allowing millions to see a partial eclipse

Hopkinsville, Kentucky will see 2min 40sec of totality in an eclipse lasting nearly three hours

A solar eclipse occurs when the Sun, Moon and Earth align

A full shadow (umbra) traces a line across the surface of the Earth. In the 21 August event this shadow will be about 70 miles wide

A bigger penumbra (partial shadow) can be seen over a much greater area, allowing millions to see a partial eclipse

Hopkinsville, Kentucky will see 2min 40sec of totality in an eclipse lasting nearly three hours

A solar eclipse occurs when the Sun, Moon and Earth align

A full shadow (umbra) traces a line across the surface of the Earth. In the 21 August event this shadow will be about 70 miles wide

A bigger penumbra (partial shadow) can be seen over a much greater area, allowing millions to see a partial eclipse

Hopkinsville, Kentucky will see 2min 40sec of totality in an eclipse lasting nearly three hours