Continental Europe’s first total solar eclipse in decades will briefly turn day to dark across several countries on Wednesday, drawing armies of sky watchers.

The coincidence of Earth, the moon and the sun falling into perfect alignment — a fleeting celestial event known as totality — has created a frenzy. People are paying exorbitant hotel rates to be in the inner part, or umbra, of the lunar shadow. Along that path, if the sky is clear, the sun will seem to become a black disk ensconced in a hazy corona, surrounded by planets and stars.

In Spain, normally empty towns have filled up. Other people have trekked to far-flung North Atlantic destinations.

The eclipse will begin at about 6:08 p.m. Central European Time in the northernmost part of Russia, its shadow swooping over the Arctic Ocean, narrowly missing the North Pole. It will reach remote Greenland, then Iceland, where viewing parties are planned in Reykjavik for a totality that will last for one minute.

It will then cut across a swath of Spain, as much as 40 percent of the country. But one of the worst fire seasons in Spanish history has left some watch parties and other activities canceled. Extreme heat is expected on Wednesday, and officials fear that negligent enthusiasts in wooded areas like the Sierra Norte could spark fires, or that people might get too close to active ones while searching for a vantage point.

New York Times journalists will provide live coverage of the eclipse from Spain, Iceland, Britain and New York City.

Eclipses have seized the imagination since people began telling stories. In Homer’s “Odyssey,” the death of Penelope’s suitors is foretold with an omen that may have been a solar eclipse: “The sun has been obliterated from the sky, and an unlucky darkness invades the world.”

That strange moment of totality will be the main event on Wednesday. Much light will go out of the sky and warmth out of the air. Currents may change. Birdsong and the buzzing of bees may stop. Stars and planets will snap into view, and pets will freak out.

The eclipse will begin with the moon seeming to cut into the sun and then, over about an hour, slide across its surface. Then comes the totality phase, which is brief — at most, just over two minutes.

Only then, in areas of actual totality, will it be safe to look up with the naked eye — otherwise, the sun can cause significant eye damage. Protective gear must be worn even in the darkest places when the moon starts to slide off the sun’s surface again. In Spain, the Spanish National Organization of the Blind has been distributing 1.7 million pairs of eclipse glasses, giving them away with the lottery tickets that it sells.