It will send a shiver down the spines of many millions of neck-craners in cities and in fields and on mountain tops across Europe, the Middle East and Asia - where there are clear skies. It will be recorded, filmed and dissected by armies of scientists. It will be the excuse for many parties, some religious ceremonies, a fair amount of superstition and perhaps a little plain thieving. It may send some too-curious people blind.
Yet perhaps the most dramatic moments of today's heavenly conjunction, its start and its finish, take place away from human eyes, in the empty ocean. In what may be the most eerie sight of all today, the event will begin in the North Atlantic, on the American side about 250 miles east of Cape Cod, when at 10.30am British Summer Time (BST) _ half-past five in the morning locally - the Sun will rise, totally eclipsed. Black dawn.
Thus begins totality, that narrow band of once-in-a-lifetime moonshadow that will race half-way across the world, first at 6,000mph and then slowing as the Sun rises and the shadow falls less obliquely, to disappear three hours and six minutes later with an eclipsed setting Sun in the middle of the Indian Ocean.
In between, it will have touched 16 countries, starting with Britain, then in Europe tracking across France, Belgium (just), Luxembourg, Germany, Austria, Hungary, Serbia (just), Romania - where it will reach its peak - and Bulgaria. The shadow's track then shoots across the Black Sea and thence over Turkey, Syria (just), Iraq, Iran, Pakistan and India, before, in a twilight that suddenly disappears, the weird dark disc of the Sun slips below the horizon of the Bay of Bengal.
The Isles of Scilly take the global honours: they will receive the shadow first at 11.10 this morning and darkness is predicted to last one minute and 42 seconds.
Cornwall and south Devon are set to follow. But the South-west, which has invested so much hope and so much hype in this first total eclipse to be visible from Britain since 1927, may be denied its hundred-second sensation for a million pairs of eyes; by a cruel twist of fate, the area where the eclipse is total in Britain is that with the least likelihood of clear skies today - no more than a 10 per cent chance.
The million pairs of eyes will be there, though. After the weekend worry about damp squibs, yesterday and last night cars were pouring into the South-west in their thousands.
Visibility prospects improve further along the shadow's track. Eastern France is already a better bet. The historic cathedral town of Noyon in Picardie, Calvin's birthplace, was yesterday confident of 60,000 visitors, quadrupling the population. "People are very excited," said the Office of Tourism's director, Virginie van Hove.
Paris, which will see an almost complete eclipse, weather permitting, has a controversy of its own. The fashion designer Paco Rabanne, he of the striking designs, the aftershave and the New Age pronouncements, is predicting that the city of light will disappear in a ball of fire as the Sun is darkened, when the Russian space station Mir crashes down upon it. It is in the writings of Nostradamus, he says. He has taken himself off to Brittany, just to be on the safe side.
Yet nothing daunted, a group of Parisians calling themselves Merde a l'Apocalypse, have invited fellow citizens to a "survivor's aperitif" in front of Rabanne's boutique on the Rue du Cherche-Midi at 12:23pm local time, one minute after the city's predicted devastation.
The shadow will not linger in Paris. At nearly 2,000mph it will darken Luxembourg then cross Germany and race across Eastern Europe where the views will probably be the best: in the central Romanian city of Ramnicu Valcea it will be at its longest, enduring two minutes and 22 seconds. There the United States space agency Nasa has set up its telescopes; British scientists have gone one country further, and will be observing from Bulgaria.
And then the descent of the dark Sun to the sea, like a returning space probe arcing across Asia, and splashing down.Reuse content