Hundreds of thousands of tourists have gathered in the north Chilean desert to experience a rare combination for astronomy buffs: a total eclipse of the sun viewed from beneath the world’s clearest skies.

Eclipse-watchers in Chile were not disappointed, when a 150-kilometre band of total darkness moved eastward across the Pacific Ocean, making landfall in Chile on Tuesday afternoon.

Totality made its first landfall over South America near the coastal Chilean city of La Serena at 4.39pm (local time). Parts of the Earth were plunged into darkness for up to two-and-a-half minutes at a time as the eclipse moved across the continent.

☀️😎 Chileans gathered to witness a total solar #eclipse on Tuesday evening!

Check out the scene from La Serena on the Pacific Ocean….#EclipseSolar2019 #EclipseChile pic.twitter.com/MIq0uHIwpw

— WeatherNation (@WeatherNation) July 3, 2019

A solar eclipse occurs when the moon passes between the Earth and the sun, bringing apparent nightfall. Tuesday’s was the first solar eclipse for the world since one crossed the US in August 2017.

The best views were from Chile’s sprawling Atacama desert north of La Serena, where a lack of humidity and city lights combine to create the world’s clearest skies.

By sunrise on Tuesday, hundreds of vehicles lined the 150-kilometres of highway between La Serena and La Silla Observatory, as people jostled for a good spot to watch the eclipse. Skywatchers set up camp on median strips and road shoulders, bringing with them tents, tables, chairs and even barbecues.

Watching the eclipse in Santiago. Photo: Getty

Elsewhere, thousands of people flocked to other parts of Chile to see this year’s only total solar eclipse. About 25,000 tourists arrived in Paiguano, a small town of just 1000 people in the Elqui Valley, 650 kilometres from the capital, Santiago.

In Santiago, office workers poured from buildings to catch a glimpse of the phenomenon.

“This is something rare that we may never see again,” said Marcos Sanchez, a 53-year-old pensioner from Santiago.

The region had not seen an eclipse since 1592, according to the Chilean Astronomy Society. The next one is expected in 2165.

Australia’s next solar eclipses are due on December 26, 2019, and June 21, 2020.

Some of the crowd near the tiny town of Paiguano. Photo: Getty

Part of the sun seen disappearing behind a ridge at El Molle. Photo: Getty

The scene from La Silla Observatory. Photo: Getty

-with AAP