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Perseids: Meteor light show set to dazzle Perseids: Meteor light show set to dazzle
(about 5 hours later)
Skywatchers are in for a dazzling display as the annual Perseid meteor shower reaches its peak on Wednesday. Skywatchers around the world are in for a dazzling display as the annual Perseid meteor shower reaches its peak on Wednesday night.
For the first time since 2007, the shower will coincide with a new moon - making viewing conditions particularly favourable, weather permitting. Viewing is weather-dependent, however, and cloud cover is forecast to spoil the party across southern England.
At the peak, expected after 23:00 (local time), as many as 100 meteors may be seen every hour. Above the clouds, conditions are unusually favourable because the shower will coincide with a new moon.
The Perseids are pieces of Comet Swift-Tuttle; each August, the Earth passes through a cloud of the comet's debris.The Perseids are pieces of Comet Swift-Tuttle; each August, the Earth passes through a cloud of the comet's debris.
Swift-Tuttle shed this material long ago, and it is now distributed as a tenuous "river of rubble" along the comet's orbit around the Sun.Swift-Tuttle shed this material long ago, and it is now distributed as a tenuous "river of rubble" along the comet's orbit around the Sun.
These particles of ice and dust (which range from the size of a grain of sand to around as big as a pea) hit the Earth's atmosphere at about 60km/s (37 miles/s).These particles of ice and dust (which range from the size of a grain of sand to around as big as a pea) hit the Earth's atmosphere at about 60km/s (37 miles/s).
As they do so, they heat the air around them, causing the characteristic streak of light seen from the ground. As they do so, they heat the air around them, causing the characteristic streak of light.
From the ground, this shower of meteors appears to originate from a single point, called a "radiant", in the constellation of Perseus - hence the name. The meteor shower is visible across the Northern hemisphere and from as far as subtropical latitudes south of the Equator. Prime viewing hours, wherever you are, stretch from about 23:00 local time on 12 August until the morning of 13 August.
The shower is active each year from around 17 July to 24 August, although for most of that period only a few meteors an hour are visible. This is when the shower's "radiant," the point from which the meteors appear to originate, is high up in the sky. The higher the radiant, the more meteors appear all over the sky.
Prime viewing hours are from about 23:00 (local time) on 12 August until the morning of 13 August. The number of visible meteors is hard to predict accurately, but the rate could reach as high as 100 per hour.
The Perseid shower is active each year from around 17 July to 24 August, although for most of that period only a few meteors an hour are visible.
Its radiant appears within the constellation of Perseus - hence the name.
Prof Mark Bailey, the director of Armagh Observatory in Northern Ireland, said the Perseids were "one of the best and most reliable meteor showers of the year".Prof Mark Bailey, the director of Armagh Observatory in Northern Ireland, said the Perseids were "one of the best and most reliable meteor showers of the year".
Alan MacRobert, senior editor at Sky & Telescope magazine, added: "The nearly moonless sky this year means the viewing will be excellent."Alan MacRobert, senior editor at Sky & Telescope magazine, added: "The nearly moonless sky this year means the viewing will be excellent."
This is when the shower's "radiant," its perspective point of origin, is high up in the sky. The higher the radiant, the more meteors appear all over the sky. It is the first time since 2007 that the Perseid shower has coincided with a new moon.
For most people, meteor showers will be best viewed with the naked eye. Meteor observers advise finding a dark location away from artificial light and an unobstructed view of the sky. For most people, meteor showers are best viewed with the naked eye. Experts advise finding a dark location away from artificial light and an unobstructed view of the sky.
Reclining chairs or blankets are best for looking up at the sky in comfort.Reclining chairs or blankets are best for looking up at the sky in comfort.
Although the number of visible meteors is hard to predict accurately, at least one every few minutes is expected. Some skywatchers have already glimpsed - and photographed - Perseid meteors during the nights preceding the shower's peak.
Chris Boundey spent Monday night at Dunstanburgh Castle in Northumberland, UK. "The meteors seemed to be coming thick and fast overhead," he told the BBC in an email.
Will you be watching the sky for this year's Perseid meteor light show? Email haveyoursay@bbc.co.uk with your stories and pictures.Will you be watching the sky for this year's Perseid meteor light show? Email haveyoursay@bbc.co.uk with your stories and pictures.
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