“It feels like the end of the world.”
Ryan Milligan, from Ardglass, County Down, describes his experience of the total solar eclipse:
He has traveled to Asia, Australia, the Americas, and Africa to see solar eclipses with his own eyes.
The self-proclaimed “eclipse chaser” is in Mexico hoping to witness the 12th solar eclipse phenomenon on Monday.
A solar eclipse occurs when Earth's moon moves between the Earth and the sun.
Mr Milligan is a former truck driver and fish factory worker who worked for NASA and is now a senior lecturer in astrophysics at Queen's University Belfast.
Speaking to BBC News NI from Mexico, he described his experience of the eclipse as “really visceral”.
He said: “It's like the end of the world.
“You can imagine how fearful civilizations in the past were at the prospect of a solar eclipse.
“Now we're starting to understand a little bit more about them. They're a really unique way to get a feel for Earth's place in the solar system and the wonders of the extrasolar atmosphere, known as the corona. .
“It's the thrill of seeing a solar eclipse that motivates us chasers to literally go to the ends of the earth,” he added.
Milligan first witnessed a total solar eclipse in Türkiye in 2006.
He said that when the moon covers all the light from the sun and darkness fills the sky, “there's nothing like the rush of adrenaline you get when you're on the path to wholeness.”
Milligan also said the drop in temperatures adds to the excitement.
“During the day, the sun sets, the animals go to sleep, and the stars appear,” he explained.
“The hair starts to grow on the back of your neck and you get a rush of adrenaline as your brain tries to process what’s going on.
“Mexico is likely to see a temperature drop of perhaps 10 to 15 degrees.
“Imagine you’re enjoying the sun in a T-shirt and suddenly you want to put on a jacket, the drop-off is noticeable.
“That adds to the thrill of the experience.”
Why Mexico?
The 48-year-old carefully chose Mazatlan, Mexico, on the Pacific coast, as his prime location, rejecting popular tourist spots such as Niagara Falls, which is under a state of emergency due to expected crowds.
He said weather was always the “ultimate factor”.
“We've been planning for a year because it passes through such a densely populated area.
“You also need to organize a map of the eclipse path, make sure you're in the best spot, and try to plan B or C in case clouds roll in,” he added.
Where and when can you see a solar eclipse in the UK?
The moon's full shadow ends its journey across the globe in the Atlantic Ocean, about 620 miles (1,000 km) from Cornwall.
You need to be on high ground and have clear skies.
What will the weather be like on Monday?
In Northern Ireland and western Scotland, the moon covers about 20% of the sun, so the weather is less than ideal.
BBC Weather said Monday will be cloudy in most areas, with rain expected in south-west Scotland and Northern Ireland.
Wales and western England will only see a small slippage of 2% to 10% of the eclipse, and the weather will be cloudy with rain.
When is the next total solar eclipse?
The next total solar eclipse is expected in August 2026, but it will be a little closer.
“There hasn't actually been a total solar eclipse in Europe since 2015, and total solar eclipses have only occurred in the Faroe Islands and Svalbard,” Milligan said.
“That year I went to the Faroe Islands and of course it was cloudy due to the weather in the North Atlantic. I couldn't see the whole picture and it was very disappointing.”
“Europe has not seen a total solar eclipse for decades, and to see them I have had to travel all over Asia, twice to Australia, twice to South America, twice to North America, and even to Africa. It was.
“I’m really looking forward to having this installed in my backyard in a few years.”