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Sun and Moon set to put on show Sun and Moon set to put on show
(20 minutes later)
Skywatchers across the globe can see a total eclipse of the Sun on Friday. Skywatchers around the globe can see a total eclipse of the Sun on Friday.
A dark shadow will sweep across the surface of the planet in a broad arc as the Moon passes directly between the Earth and our star.A dark shadow will sweep across the surface of the planet in a broad arc as the Moon passes directly between the Earth and our star.
The eclipse begins in Canada's high Arctic and ends in northern China's Silk Road region.The eclipse begins in Canada's high Arctic and ends in northern China's Silk Road region.
"Totality" will be at its greatest at 1021 GMT, when a 236km swathe of northern Russia will be plunged into darkness for two minutes, 27 seconds. Parts of northern Russia will go dark for two minutes, 27 seconds from 1021 GMT - but Britain will only experience a partial eclipse around 1016 BST.
A partial eclipse will be seen across a much wider region, which includes north-eastern North America, most of Europe (including the UK) and Asia. That partial eclipse will be seen across most of Europe, Asia and north-eastern North America.
As is always the case with eclipses, tourists and amateur and professional astronomers have been flooding towns in the best viewing locations - along the path of totality.As is always the case with eclipses, tourists and amateur and professional astronomers have been flooding towns in the best viewing locations - along the path of totality.
In Novosibirsk, Siberia's cultural and scientific capital, more than 5,000 foreign tourists were expected to show up in the city.In Novosibirsk, Siberia's cultural and scientific capital, more than 5,000 foreign tourists were expected to show up in the city.
"The viewing points will be set up in the very beautiful historical and cultural places of Novosibirsk, there will be a number of telescopes there. Thirty-eight telescopes will be set up in the park on the River Ob embankment," said local official Alexei Borisek."The viewing points will be set up in the very beautiful historical and cultural places of Novosibirsk, there will be a number of telescopes there. Thirty-eight telescopes will be set up in the park on the River Ob embankment," said local official Alexei Borisek.
Total solar eclipses usually take place about once every 18 months, and always at new Moon - when the lunar body sits directly between the Sun and the Earth.Total solar eclipses usually take place about once every 18 months, and always at new Moon - when the lunar body sits directly between the Sun and the Earth.
However, they do not happen every new Moon. The lunar orbit is slightly tilted to that of our planet and therefore the Moon's shadow often misses the Earth.However, they do not happen every new Moon. The lunar orbit is slightly tilted to that of our planet and therefore the Moon's shadow often misses the Earth.
The Moon's shadow has two parts: an umbra and a penumbra.The Moon's shadow has two parts: an umbra and a penumbra.
The umbra is the "inner" part of the Moon's shadow, and people inside this zone will witness the full glory of the eclipse. The penumbra is the Moon's faint "outer" shadow. It will only give surface viewers a partial eclipse.The umbra is the "inner" part of the Moon's shadow, and people inside this zone will witness the full glory of the eclipse. The penumbra is the Moon's faint "outer" shadow. It will only give surface viewers a partial eclipse.
This will be the case for skywatchers in the UK, for example.Proper protective gear for the eyes is essential for safe viewingThis will be the case for skywatchers in the UK, for example.Proper protective gear for the eyes is essential for safe viewing
In London, where the Moon's disc takes its biggest bite out of the Sun at 1016 BST (0916 GMT), a maximum of 12% of the star will be blotted out.In London, where the Moon's disc takes its biggest bite out of the Sun at 1016 BST (0916 GMT), a maximum of 12% of the star will be blotted out.
Conditions are better further north. In Lerwick in the Shetland Isles, the Moon will obscure as much as 36% of the Sun.Conditions are better further north. In Lerwick in the Shetland Isles, the Moon will obscure as much as 36% of the Sun.
Astronomical groups have reminded the public that viewing the Sun without protective equipment - even in partial eclipse phases - can result in a retinal burn and permanent eye damage.Astronomical groups have reminded the public that viewing the Sun without protective equipment - even in partial eclipse phases - can result in a retinal burn and permanent eye damage.
Viewing the Sun's harsh light should only be done through proper solar telescopes or glasses, or through a pinhole projection system.The path of the Moon's shadow will cover more than 10,000kmViewing the Sun's harsh light should only be done through proper solar telescopes or glasses, or through a pinhole projection system.The path of the Moon's shadow will cover more than 10,000km
Totality is timed to begin at sunrise at 0921 GMT in Queen Maud Gulf off Victoria Island in the territory of Nunavut, Canada.Totality is timed to begin at sunrise at 0921 GMT in Queen Maud Gulf off Victoria Island in the territory of Nunavut, Canada.
The instant of greatest eclipse occurs at 1021 GMT close to the Russian city of Nadym.The instant of greatest eclipse occurs at 1021 GMT close to the Russian city of Nadym.
Totality ends at 1121 GMT near the Chinese city of Xi'an in Shaanxi province.Totality ends at 1121 GMT near the Chinese city of Xi'an in Shaanxi province.
In all, the Moon's umbra will have travelled along a path approximately 10,200km long.In all, the Moon's umbra will have travelled along a path approximately 10,200km long.