A graphic showing the Earth passing through a trail of comet debris as the planet circles the Sun
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Why does the Perseid meteor shower happen every year?

Cloud and rain are expected to make viewing the annual Perseid meteor shower disappointing in the south of the UK.

But clearer skies in northern England and Scotland are likely to give skywatchers here a better experience.

At the peak, expected after 23:00 (local time), as many as 100 meteors may be seen every hour.

The BBC's Pallab Ghosh explains why the meteor shower happens every year.

  • 12 Aug 2015
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