Millions turned their eyes to the sky on both sides of the Pacific as a solar eclipse created a "ring of fire" from Asia
to the western United States.
The annular eclipse was visible from parts of China early on Monday before moving westwards across Taiwan and Japan, continuing across the Pacific on a 13,600km arc ending in Texas late on Sunday local time.
Travelling on a diagonal path, the eclipse crossed parts of Oregon, Nevada, Utah, Arizona and New Mexico before disappearing in Texas with the sunset.
As it reached its peak, a crowd of several thousand viewers gathered in a Utah field took a collective gasp and
erupted into applause, cheers and even some howling.
"The wonder of it, the sheer coincidence that this can happen, that totally amazes me," said Brent Sorensen, a physics professor at Southern Utah University, who brought a half-dozen telescopes to the rural town of Kanarraville for the public to peek through. "It never ceases to amaze me."
Eclipses of some type occur almost every year, but stargazers have not seen an annular - shaped like a ring - eclipse on US soil since 1994, and the next one is not to occur until 2023.
That is because the phenomenon requires a particular set of orbital dynamics, NASA Space Scientist Jeffrey Newmark said.
An annular eclipse occurs when the moon's orbit is at its furthest point from the Earth and closer to the much larger sun. That juxtaposition allows the moon to block more than 90 per cent of the sun's rays when the two orbs slide into alignment.
"It's like moving your fist in front of your eyes," Newmark said. "You can block out the view of a whole mountain. It's the same kind of effect."
The current eclipse did not turn day into night, but daylight faded as the moon slid in front of the sun and then slowly returned as the moon moves away.
From start to finish, the eclipse was visible for just under two hours. A view of the so-called "ring of fire" spectacle at the eclipse's peak, however, only lasted about four minutes, and even then was only visible to viewers positioned along the centreline of the eclipse's path.
Despite its infrequent nature, Inese Ivans, an assistant professor of astronomy and astrophysics at the University of Utah, said an annular eclipse did not have particular significance, but rather was part of the normal astronomical cycle.
"It reminds us that the earth is spinning. That everything is constantly in motion," Ivans said.
In Asia, clouds across much of southeastern China prevented a clear view of the event, with some early risers in Hong Kong able to see only a small sliver of the annular eclipse and others coming away disappointed.
In Japan, "eclipse tours" were arranged at schools and parks, on pleasure boats and even private aircraft. Similar events were held in China and Taiwan as well.
Many in Tokyo got a spectacular sight as the city received its first glimpse of the phenomenon in 173 years.
Commuters from businessmen to schoolchildren stopped on the streets to watch as the eclipse developed, cheering when it became visible.
Japan Airlines laid on a sold-out observation flight. Electronics giant Panasonic sent an expedition to the top of Mount Fuji, Japan's highest mountain at 3,776m, to film the phenomenon using solar-powered equipment.
The eclipse was broadcast live on television in Tokyo. Taipei's astronomical museum opened its doors at dawn while Hong Kong's space museum set up solar-filtered telescopes outside its building on the Kowloon waterfront.
In Hong Kong, heavy cloud cover gave most viewers only a brief window of less than a minute, while others higher up got a marginally better view through the clouds.