The idea of longtime headliner Ozzy Osbourne playing an afternoon set at a festival might have seemed odd to many fans. But it was a concept perfectly timed for him to open with "Bark at the Moon" during a solar eclipse.

The performance happened in August 2017 at the Moonstock Festival in Carterville, Ill., and, as you can see in the video above, the sky was relatively bright when Osbourne and his band took the stage to music from Carl Orff's Carmina Burana. But less than two minutes into "Bark at the Moon," everything went dark. The fan who shot the video panned up to capture the very moment the moon blocked out the sun. The eclipse was over by the time the song ended.

The four-day Moonstock festival was specifically designed to celebrate the eclipse, with Osbourne's set being the only performance on the main stage that day. The Southern Illinois location was chosen because it was roughly where the eclipse would be able to be seen for the longest duration -- approximately two-and-a-half minutes. Festival attendees were given protective glasses so they could view the eclipse. Black Stone Cherry, Halestorm and Five Finger Death Punch headlined over the course of the weekend.

Watch Ozzy Osbourne Perform During a Solar Eclipse

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Gallery Credit: Jen Austin, UCR Staff

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