By David Dickinson, Postmedia News May 16, 2012

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The first eclipse of 2012 graces Earth this weekend, and much of North America will witness the event Sunday night. On May 20, an annular eclipse will span the Pacific, from China and Japan at sunrise to the U.S. southwest at sunset.

Unlike a total solar eclipse, an annular occurs when the moon is very near apogee, its farthest point from the Earth. It appears slightly smaller than the visible disk of the sun, leaving a bright "annulus" or solar ring amounting to about 5 per cent of the solar disk.

The path of the eclipse — more than 200 kilometres wide — touches down at 8:56 p.m. GMT and departs the planet's surface at 2:49 a.m. the next day.

Several unique locations lay within the central path of the eclipse, including Japan's Mt. Fuji, Utah's Bryce Canyon, the Grand Canyon and the Very Large Array of radio telescopes in Socorro, New Mexico.

Although Canada won't see a full annular eclipse, most of the country from northern Quebec westward will see a deep partial. The farther south and west you are, the bigger the "bite" that the Moon will take from the sun.

Vancouver, for example, will witness a maximum 80 per cent partially eclipsed sun right around 6:15 p.m. local time.

A word of warning: though 95 per cent sun blockage seems like a lot, the remaining 5 per cent is surprisingly bright. You will need to take safety precautions when viewing the sun throughout all phases of the eclipse. That said, don't let the dire warnings that are sure to be repeated scare you away from watching the eclipse — it can be easily enjoyed with little equipment.

The two safe methods for viewing solar eclipses are via projection or with an approved telescopic filter for observing the sun. Never use a filter that fastens to the eyepiece, as seen in some older telescopes; a safe filter fastens to the front of the telescope to avoid overheating and cracking.

A homemade solar projector can be built with nothing more than a shoebox, some tape and aluminum foil. This is a "camera obscura," and it will come in handy also for observing the transit of Venus in just a few weeks on June 5 and 6.

This will be the first annular eclipse to be seen from the United States since May 10, 1994. The drought of total solar eclipses over the U.S. will end five years from now on August 21, 2017 with a continent-spanning eclipse, and Canadian observers can expect the next total solar eclipse to cross central Ontario and northern Quebec on June 10, 2021.

Eclipse-chasing can be an addictive hobby. If you want to catch it, start planning now!