Millions in Asia and western North America watched as a rare "ring of fire" eclipse crossed their skies.

Cloudy skies prevented British Columbians from getting a look at the annular eclipse, in which the moon passes in front of the sun leaving only a golden ring around its edges.

It was visible to wide areas across Asia early Monday and in parts of the western United States Sunday afternoon.

People from Colorado, Oklahoma and as far away as Canada travelled to Albuquerque, N.M., to enjoy one of the best vantage points.

Members of the crowd smiled and cheered and children yelled with excitement as the moon crossed the sun and the blazing halo of light began to form. Eventually, the moon centred and covered 96 per cent of the sun.

"That's got to be the prettiest thing I've ever seen," said Brent Veltri of Salida, Colo.

Albuquerque city officials had urged residents to go to organized events or watch one of the many live webcasts to avoid damaging their eyes. The eclipse cannot be viewed with the naked eye or even sunglasses. And solar glasses, which make the sun look like a huge orange disc, are a rare commodity in communities along the eclipse's path.

In Japan, "eclipse tours" were arranged at schools and parks, on pleasure boats and even private airplanes. Similar events were held in China and Taiwan as well, with skywatchers warned to protect their eyes.

The eclipse was broadcast live on TV in Tokyo, where such an eclipse hasn't been visible since 1839. Japanese TV crews watched from the top of Mount Fuji and even staked out a zoo south of Tokyo to capture the reaction of the chimpanzees — who didn't seem to notice.

A light rain fell on Tokyo as the eclipse began, but the clouds thinned as it reached its peak, providing nearly perfect conditions.

"It was a very mysterious sight," said Kaori Sasaki, who joined a crowd in downtown Tokyo to watch event. "I've never seen anything like it."

Hong Kong skywatchers weren't so lucky.

Several hundred people gathered along the Kowloon waterfront on Hong Kong's famed Victoria harbour, most of them students or commuters on their way to work. The eclipse was already underway as the sun began to rise, but heavy clouds obstructed the view.

The eclipse followed a narrow 14,000-kilometre path for 3½ hours. The ring phenomenon lasted about five minutes, depending on location. People outside the narrow band for prime viewing saw a partial eclipse.

"Ring of Fire" eclipses are not as dramatic as a total eclipse, when the disk of the sun is entirely blocked by the moon. The moon is too far from Earth and appears too small in the sky to blot out the sun completely.