Patience and peripheral vision: Perseid shower reaches peak

It is time for stargazers to dig out their deckchairs and look skyward for what is considered to be one of the best meteor showers of the year.

- Nicola Davis

The Perseids are due to peak tonight. They have been active from mid-July and will continue to be visible for a further couple of weeks.

The annual event is caused by comet debris burning up in Earth's atmosphere. "Each year, Earth passes through the material shed by an ancient celestial body, Comet 109P/Swift-Tuttle, which is estimated to be well over 5bn years old - older even than Earth," said Dr Richard Parker, an astrophysicist at the University of Sheffield. He said the comet visited the inner solar system every 133 years, and would next make its closest approach to Earth in 2126.