A total solar eclipse has seen millions of people across a heavily populated swath of North America gazing toward the heavens, as the Moon completely blocked the Sun for more than four minutes in some places.
The eclipse was viewable, weather permitting, along a path starting in Mexico and then crossing through the United States and into Canada.
The resort city of Mazatlan in Mexico was one of the first places in the world to see the phenomenon unfold.
Cheers rang out along the beach as the Moon began to pass over the Sun.
Hundreds in a beachside park had passed the waiting time by readying their equipment and listening to a youth orchestra play Star Wars songs while a large screen projected images of Princess Leia behind them.
Luz Elena Aguillón de la O sat in the grass with a group of family and friends who had gathered from Mexico City, Guanajuato and Mazatlan to take in the spectacle.
"Happy to be here with family, friends sharing a singular, unrepeatable event that the universe and nature give us," she said.
Lourdes Corro, 43, travelled 10 hours by car to get to Mazatlan.
"The last one I saw was when I was 9-years-old," Ms Corro said.
"There are a few clouds but we can still see the Sun."
Eclipse fans are gathering in numerous places along the "path of totality", which stretches from Mexico's Pacific coast through Texas and across 14 other US states into Canada.
In upstate New York, at the Frontier Town campground in North Hudson, children ran around wearing eclipse T-shirts, while parents set up tables, chairs and eskies.
Connecticut residents Bob and Teresa Love were stretched out in the cargo bed of their pick-up truck, eating pastries and hoping the forecasted clouds would hold off.
"I'm trying not to get too excited because of weather, just trying to keep expectations real," said Teresa, 49.
"Some people say it's life-changing. I don't know if it's going to be life-changing, but I think it's going to be cool to see."
At up to 4 minutes and 28 seconds, the total eclipse of 2024 surpasses the duration of the one that traversed the United States from coast to coast in 2017.
That one clocked in at up to 2 minutes and 42 seconds. According to NASA, total eclipses can last anywhere from 10 seconds to about 7-1/2 minutes.
Other cities along the path of totality include: San Antonio, Austin and Dallas, in Texas; Indianapolis, in Indiana; Cleveland, in Ohio; Erie, in Pennsylvania and Montreal, in the Canadian province of Quebec.
The main attraction at Niagara Falls is typically the more than 750,000 gallons of water that rush over the brink every second. On Monday, it was the eclipse.
Tourists streamed into Niagara Falls State Park with wagons, strollers, coolers and chairs. Photographers' tripods lined a railing under cloudy skies.
US President Joe Biden posted a brief video on X to encourage Americans to wear eye protection when viewing the eclipse — in a subtle dig at his predecessor and 2024 rival, former president Donald Trump.
"Folks, enjoy the eclipse, but play it safe, don't be silly," Mr Biden said in a video showing him donning eclipse glasses and looking skyward from the balcony outside the Blue Room of the White House.
That's the spot where Trump glanced up toward the Sun without eye protection in 2017.
Overcast skies are among an eclipse-chaser's worst fears. The US National Weather Services forecast as of Monday morning was for "a rapid untimely increase of clouds" in Southern Texas; less worrying "high thin clouds" for a swathe from Arkansas to the Midwest; and the clearest skies in northern New England.
It will take about 80 minutes from the moment the Moon first begins to cover the Sun to the moment of totality, then another 80 minutes to complete the process in reverse.
Eclipse veterans have described the 15 minutes before totality as foreboding, with shadows becoming oddly crisp and sunshine assuming an eerie quality. In the seconds before totality, a phenomenon called "shadow bands" may appear, shimmering shadows on the ground, like those seen on the bottom of a swimming pool.
Some stars will also appear in the daytime sky as dusk abruptly descends, sending temperatures dipping. Birds and other wildlife, reacting to the sudden darkness, often fall silent and still.
The last remaining bit of brilliant sunlight before totality creates a "diamond ring effect" in which a single bright spot appears along the lunar edge even as the Sun's corona leaves a ring of light around the Moon.
ABC/wires
