Friday, August 1 is a red-letter day for eclipse enthusiasts. On that date, the sun will be partially eclipsed over an immense area that includes western and central Asia, parts of northern and central Europe, all of Greenland and even a small slice of northeastern North America.

A total solar eclipse — the first in nearly two and a half years — will be visible along a narrow track that will start over the Northwest Passage of Canada, gives a glancing blow to northern Greenland, then shifts southeast through Siberia and western Mongolia and before ending near the famed Silk Route of China.

The path of totality for this upcoming eclipse is never more than 157 miles (252 km) wide.

Where it's visible

The total eclipse begins at sunrise over Northern Canada's Queen Maud Gulf, where the moon's umbra will first touch down on the Earth, resulting in Canada's hosting its first total solar eclipse since February 26, 1979.

As the sun comes into view over the north-northeast horizon its disk will become completely blocked by the moon. This is in the area of the famous Northwest Passage, a sea route connecting the Atlantic and Pacific Oceans through the Arctic archipelago of Canada. The various islands of the archipelago are separated from one another and the Canadian mainland by a series of Arctic waterways collectively known as the Northwestern Passages. Politically, this region belongs to Nunavut, the largest and newest of the territories of Canada; it was separated officially from the vast Northwest Territories on April 1, 1999.

Although the umbral shadow narrowly misses the towns of Cambridge Bay on Victoria Island, and Resolute on Cornwallis Island, its northern edge just clips the northernmost permanently inhabited place in the world: Canada's remote outpost of Alert, which lies just 508 miles (817 km) from the North Pole and has a population of just 5. Here, totality will last 43 seconds.

Crossing the open Arctic, the southern half of the totality path slides across the many fjords of northermost Greenland, coming to within 450 miles (720 km) of the North Pole at 9:38 UT over the Arctic Ocean before turning southeast. Totality sweeps over the Norwegian island group of Svalbard, while the northern edge of the umbra's path just grazes Russia's Franz Josef Land island group, then cuts across the crescent-shaped island of Novaya Zemlya on its way to central Asia. The umbra first touches the Russian coast on the Yamal Peninsula. Not far inland, greatest eclipse, producing 2 minutes 27 seconds of totality, is attained near the town of Nadym (pop. ~46,000), just inland from the boot-shaped Gulf of Obskaja.

Spending part of your summer in Siberia may sound a bit more appealing upon hearing that the central path passes almost directly over the city of Novosibirsk, Russia's third most populous city (pop. ~1.4 million) where totality begins at 10:44 UT and will last 2 minutes 18 seconds. The center of the path will then follow the Mongolia-China border for several hundred kilometers, with Olgij, Mongolia getting 1 min 36s of totality. Totality finally whisks into north-central China, crossing the west end of the Great Wall before leaving the Earth at a point northeast of the major city of Xi'an (pop. 3.9 million).

The northern half of Maine as well as the Canadian Maritime Provinces will experience a partial eclipse at sunrise.

Eclipse expedition

A most unusual attempt to rendezvous with the moon's shadow will be made by an Airbus A330-200 twin-engine long-range aircraft. Following a flight plan optimized specifically for the purpose of viewing this eclipse, all of the many unusual requirements of this flight have been evaluated and satisfied with arrangements by the air charter company Deutsche Polarflug (AirEvents) which has previously operated successful over-flights of the North Pole with this same aircraft.

Glenn Schneider, from the University of Arizona's Steward Observatory and a veteran of 26 total eclipses, has worked out the detailed formulation of the flight plan. He is targeting a point from the high polar north, at approximately +83-degrees latitude and about 440 nautical miles from the North Pole at an altitude of 37,000 feet above the Arctic Ocean.

This will be a unique event in the annals of solar eclipse-chasing since there are no records of any total solar eclipse observations as far north as this. While total solar eclipses in the polar regions are not rare, accessibility is very difficult. Until this juncture in time (and technology) very high-latitude (north or south) total solar eclipses have been elusive. The total solar eclipse of 23 November 2003 was the first in history to have been observed from the Antarctic.

Once again it needs repeating: to look at the sun without proper eye protection is dangerous. Even if you are in the path of the total eclipse you will need to protect your eyes during the partial phases.