- Jonathan Amos
- BBC science correspondent
Thursday, the northern hemisphere will witness a unique celestial eclipse of the sun, but the inhabitants of the Arab world will not be able to watch it, unfortunately.
This event is known as an annular eclipse of the sun, where you see the moon moving across the face of the sun, but it does not completely block the light emitted by it.
Instead, a thin, sparkling ring will appear around the sun’s disk.
Perhaps the best place on Earth to view this eclipse is the North Pole.
It is true that not many people live there, but a large part of the population of the globe will enjoy watching a partial eclipse, in which the moon appears to be nibbling a large part of the sun.
These include the eastern United States, northern Alaska, along with much of Canada and Greenland, and parts of Europe and Asia.
Scotland will be the most suitable place to watch the eclipse in Britain, in terms of the size covered by the disk of the sun. The advice of scholars when watching is not to try to look at the sun with the naked eye, as this may cause serious harm to the beholder.
And anyone staring at the sky should use protective vision equipment, such as approved eclipse glasses or a perforated projector.
And the “annular path”, which is the path across the Earth’s surface where the moon appears completely inside the sun’s disk in a wonderful scene, begins at sunrise in Ontario, Canada, at 09:49 GMT.
The place where the beholder enjoys the greatest duration of the eclipse, which is about four minutes, is the region in the middle of the Nares Strait, the narrow channel separating the Canadian archipelago from Greenland.
Elsewhere, there will be a chance of seeing 90 percent of the sun’s disk.
Not every eclipse can be total, as the moon’s orbit around the Earth is not perfectly circular. The distance of the moon from the earth ranges between about 356.500 km and 406.700 km.
This difference makes the apparent size of the moon in the sky variable by 13 percent.
“The eclipse gives us a chance to connect with the sun,” said university professor Lucy Green, who works in the UCLA Space Science Laboratory.
She added: “The sun is usually amazingly bright, and we kind of don’t pay much attention to it. But during an eclipse, in one way or another, we can – if we look safely – watch the moon slide in front of the sun, and this reminds us of the solar system we live in, and works on around the clock”.