‘The scale of the universe is almost impossible for us to imagine’

WHEN Sadhbh Leahy was born in August 1999, her father abandoned a solar eclipse expedition to rush home for her arrival. Twenty-seven years later, the Hurdlestown woman found herself helping explain Ireland's latest solar eclipse to the nation.

As Public Engagement Officer with the Dublin Institute for Advanced Studies (DIAS) at Dunsink Observatory, Sadhbh was one of the scientists at the forefront of public engagement ahead of last week's spectacular celestial event, appearing across national media and helping thousands of people understand one of the most significant eclipses visible from Ireland in decades.

It was, in many ways, a fitting role for the young astrophysicist whose own story has been intertwined with eclipses from the very beginning.

Speaking to the Meath Chronicle, Sadhbh recalled how her father, John had organised an expedition to Cork for amateur astronomers hoping to secure the best possible view of Ireland's 1999 solar eclipse.

“He was there a couple of days early when he got a phone call at four o'clock in the morning to say my mum, Mary was in labour, so he had to rush back to Drogheda because I wanted to be born,” she laughed.

“The following day was the eclipse and all the people he had brought to Cork saw nothing because it was cloudy. Because he was back in Meath after I had been born, he was actually the only one of the group who got to see it.

“There have been lots of jokes over the years that I was always destined to end up working in astronomy.”

Whether it was fate or coincidence, the fascination with science that followed has taken Sadhbh from the quiet countryside outside Kells to one of Ireland's leading astronomical institutions.

Raised in Hurdlestown, between Navan and Kells, she attended Oristown National School before moving on to O'Carolan College, Nobber.

She describes herself as an academic child who always enjoyed science, although she never imagined where that interest would eventually lead.

“I was always kind of academic in school and always enjoyed science,” she said, explaining that her love of physics gradually developed into a passion for astrophysics while studying at Trinity College Dublin.

She graduated with first-class honours in Physics and Astrophysics in 2022, while also completing qualifications in innovation, entrepreneurship and business before joining DIAS later that year.

Today she is responsible for public engagement at Dunsink Observatory, Ireland's oldest observatory, where she organises educational programmes, public events and the hugely popular Race to Space escape room, helping people of all ages discover the wonders of astronomy.

Last week proved one of the busiest of her career.

Interest in Tuesday evening's solar eclipse exceeded all expectations, with thousands of people gathering across Ireland to witness the Moon gradually pass in front of the Sun.

“I mean, it was just incredible,” she said.

“Seeing the scale of interest was phenomenal. We anticipated there would be a lot of interest, but it was off the scale of even what we had imagined.

“Because it wasn't a total eclipse, we thought maybe people wouldn't care as much. But seeing what it turned into was phenomenal.”

Although Ireland lay outside the narrow path of totality, the country came remarkably close, making it one of the most significant eclipses visible here in decades.

“We were really close to the line of totality, so we experienced around 92 to 98 per cent of the Sun being covered,” Sadhbh explained.

“It made it a really significant eclipse for Ireland.”

Behind the scenes, however, the eclipse represented far more than a spectacular sight for skywatchers.

Months of planning culminated in a major scientific mission involving researchers from DIAS, Trinity College Dublin, Technological University Dublin and the Italian National Institute for Astrophysics.

Working alongside the Irish Air Corps, scientists flew hundreds of kilometres west of Ireland to intercept the path of totality, where they could study one of the Sun's greatest mysteries — the solar corona.

“There is still so much that we don't know about the Sun,” Sadhbh said.

While the Sun's visible surface reaches temperatures of several thousand degrees, its outer atmosphere — known as the corona — reaches millions of degrees, something scientists are still trying to understand.

“The eclipse gives researchers a rare opportunity to study the corona in incredible detail and hopefully answer some of those questions.”

It is easy to forget, she says, that despite being Earth's nearest star, the Sun still holds countless mysteries.

In fact, one of the most important areas of research focuses on space weather — solar storms capable of disrupting satellites, communications systems and even power infrastructure.

Many people associated the spectacular displays of the Northern Lights seen over Ireland in recent years with climate change.

Fortunately, Sadhbh says, that isn't the case.

“It's something people ask us a lot,” she said.

“The good news is that it has nothing to do with climate change.

“The Sun goes through a cycle every eight to eleven years where it becomes much more active. That's why we've seen the aurora much more frequently in Ireland.

“The aurora are beautiful, but the solar storms that create them can also affect communications and infrastructure, so understanding them is really important.”

Despite spending every day thinking about stars, planets and galaxies, Sadhbh says the sense of wonder has never faded.

“The scale of the universe is almost impossible for us to imagine,” she reflected.

“It kind of makes you step back from everyday life and look at the bigger picture.”

Of course, there is one question almost everyone asks an astronomer.

Are we alone?

“I think there probably is life somewhere else,” she admitted.

“There's no science to back that up because we haven't found anything yet.

“But when you think about the scale of the universe, I think it's unlikely that there isn't life somewhere else.

“Maybe we just haven't found it yet.”

If she ever had the chance to leave Earth herself, she wouldn't hesitate.

“I would love to go to space,” she laughed.

“If there's any tickets going, I'd love to go.”

For now, however, she is content helping others discover what lies beyond our own planet.

Her advice to anyone wanting to reconnect with the night sky is refreshingly simple.

Forget expensive telescopes.

Start with the Moon.

“People might think that's a boring answer,” she said.

“But because it changes so much during the month, there's always something new to see. If you have a telescope, seeing the craters on the Moon is incredible.”

She also encourages people to keep an eye out for Jupiter, Saturn and Mars, pointing out that what appears to be an unusually bright star may in fact be another world millions of kilometres away.

Asked about the most breathtaking sight she has witnessed through a telescope, her answer comes instantly.

“The moons around Jupiter and the rings around Saturn,” she said.

“The fact that you can see them in such detail from here is just amazing.”

For a young woman who grew up among the fields of rural Meath, helping Ireland understand the universe might once have seemed an unlikely destination.

Yet Sadhbh hopes stories like hers will encourage other young people — particularly girls with an interest in science — to believe that careers in astronomy are within reach.

After all, as her family likes to joke, perhaps the stars really did have a plan all along.

From a father abandoning an eclipse expedition so he wouldn't miss her birth, to becoming one of the country's leading voices on the latest eclipse almost three decades later, it is a journey that proves sometimes the most remarkable stories really are written in the stars.