Astronomers are predicting a dazzling display of shooting stars tonight as the Perseid meteor shower reaches a peak in activity.
The celestial light show is one of the highlights of the astronomical calendar and this year is expected to one of the best in recent history. The bright streaks of light are caused by tiny particles of debris left by a comet hurtling into the atmosphere at 135,000mph. The particles range from the size of a grain of sand to a pea and create white-hot streaks of superheated air when they burn up.
Perseids can appear in any part of the sky, with the brightest sailing across the heavens for a few seconds before fading away. About 60 to 100 shooting stars an hour are expected to be visible at about 11pm in parts of Britain where the skies are dark and free of clouds. In cities, where light pollution obscures much of the night sky, astronomers anticipate about 10 shooting stars an hour will be bright enough to be seen. Only two days after a new moon, there will be little moonlight to affect viewing.
The meteors are called the Perseids because they appear to come from the constellation Perseus, between Taurus and the distinctive W-shape of Cassiopeia. The shower is due to peak this evening, but will continue into the early hours of Friday morning.
"Relax, be patient, and let your eyes adapt to the dark. With a little luck you'll see a shooting star every minute or so on average," said Robert Naeye, editor of Sky and Telescope magazine.
The Perseid meteors appear in August every year, when the Earth moves through the trail of the Swift-Tuttle comet, which last passed close to the sun in 1992.