London - Stargazers will be hoping for clear skies overnight on Thursday when one of the year's most spectacular meteor showers reaches its climax.
The Royal Astronomical Society said debris from the Swift-Tuttle comet will burn up in the Earth's atmosphere, creating between 60 and 100 shooting stars every hour.
If the night stays clear, the viewing conditions for the Perseid meteor shower should be "near perfect" because there will be barely any light from Tuesday's new moon.
"Our celestial neighbour will not provide any natural light pollution to spoil the view," the society said. "This year's shower looks set to be one of the best of recent years."
Despite the lack of moonlight, bad weather may ruin the view for many people. The Met Office said cloud will cover many parts of Britain during the night, although skies may clear at times in the south and west.
While most of the meteors are no bigger than a grain of sand, they create tremendous amounts of heat when they hit the atmosphere at 216 000km/h.
Most will appear as brief flashes of light, although some will streak across the sky. Peaking at around 22h00 GMT on Thursday, they should be visible to the naked eye until before dawn on Friday.
While those in the northern hemisphere will have the best view, people in the south may see a few. Even people in light-polluted cities should be able to see about 10 each hour.
Sky-gazers should look to the north-east in the direction of the Perseus constellation.
Observers will share sightings on Twitter, using the hashtag "#meteorwatch" and these will be plotted on a map by the British Astronomical Association and the Royal Astronomical Society.
Nasa said astronomers will have another treat before the shower starts. At sunset on Thursday, Venus, Saturn, Mars and the crescent moon will be tightly aligned in the western sky. - Reuters