How Cork got a science centre and space observatory in a 16th-century castle 

The Blackrock Castle telescope gives astronomers and visitors alike a window on other worlds, exploring the possibility of life on other planets, but was only set up after a chance phonecall from the US in 2002, says Jonathan deBurca Butler

Alan Gilinan at the dome that houses the telescope. Pictures: Larry Cummins

Last month, the small team at Blackrock Castle Observatory was abuzz. Their phones were hopping with requests from news outlets.

For one or two days, the world transferred its gaze from a big orange blob in the White House to a little-known planet 124 light years from our own that might, just might, contain life.

K2-18B is an exoplanet (meaning not in our galaxy) two and a half times the size of Earth. It is so far away that no sound, never mind mankind, will reach it in our lifetime. However, the space-borne James Webb telescope has had its many eyes on this exoplanet for some time. Its most recent data has people in the world of astronomy talking in excited, if whispered, tones.

“The James Webb telescope is a fantastic piece of equipment,” says Alan Giltinan, centre manager at the Blackrock Castle Observatory. “It uses what’s called spectroscopy, a technique that breaks white light down in to a type of rainbow and their individual colours and components.

“From there, you’re looking for telltale signs, or lines and dips in the curves of those colours when you look at them on a spectrum. So, let’s say methane or oxygen — chemical elements you’d find on our planet — have a very specific format, like a fingerprint. So, by comparing the spectra of exoplanets with planets with known spectra, we can try to ascertain what the atmosphere of these planets have.”

Blackrock Castle Observatory centre manager, Alan Gilinan setting up their largest telescope.

And this is why the science community is getting excited. Analysing the latest data from the Webb telescope, a group at Cambridge University found that the atmosphere of K2-18B seems to contain the chemical signature of two molecules that are associated with life: Dimethyl sulphide and dimethyl disulphide.

On Earth, these gases are produced by marine phytoplankton and bacteria.

But let’s not break out the Romulan ale just yet.

“The reality is that it’s very early to know if these are definitive signs,” says Alan. “We have one telescope, with one set of readings, at this point. We need more data. There is cautious optimism, but we’re not there yet.”

And even if we were to find life on this faraway planet, it’s highly unlikely that life would be capable of uttering words such as ‘ouch’, as in the movie ET, let alone stand up and go trick-or-treating.

“K2-18B is what is known as a super earth and would be closer to Neptune in size,” says Alan. 

It is larger than what you might hope for in terms of life, but there’s no reason it wouldn’t contain microbial life or other life forms. 

“Whether it contains upright life forms, like yourself and myself, is another matter altogether. That’s a different criteria. But it could, in principle, contain the likes of algae and plankton.”

Though it is “very close in astronomical terms” , K2-18B cannot be seen from Blackrock.

That shouldn’t deter people from being curious.

“It’s worth noting that the data from James Webb is public and so will be available to scientists of all sorts,” says Niall Smith, head of research at Munster Technological University and head of Blackrock Castle Observatory.

“It doesn’t all have to be done in Nasa or Cambridge. We can participate in looking for life in the universe by using the data. Irish people and scientists and students can be part of this search for life in the universe; it’s freely available to us all.”

Niall Smith received a call in 2002 that was the spur for an observatory in Cork. Picture: Darragh Kane

It’s that quest for knowledge that drove both Niall and Alan to establish an observatory in Cork 20 years ago.

The story behind it is one of good luck and rare open-mindedness; you could say it was written in the stars.

On a Friday evening in 2002, just as he was about to head home from his office at the then Cork Institute of Technology (CIT), Niall received a call from a Texan named Gary O’Keeffe, who wanted to know where Cork’s observatory was.

When Niall explained there was none in the area, the pair spent some time on the phone lamenting its absence, before supposing its existence. Two years later, Cork City Council bought the 16th-century Blackrock Castle, built by Queen Elizabeth to protect the city from pirates. In hope, more than expectation, Niall and Alan sent off a two-line letter to the city manager, Joe Gavin, suggesting that the castle would be the perfect site for an observatory.

Mr Gavin agreed and, in 2005, the castle was handed over to CIT (now MTU).

“Essentially, we design and build specific types of instruments, equipment, and software to help us analyse the universe in finer detail,” says Alan.

“We have 14 people working here, and at its core is an understanding of the universe we live in.

“That’s what drives a lot of people who work here. That thirst for knowledge and wanting to understand the universe we live in and it’s great that we were able to establish an observatory in Cork.”

Alan Gilinan setting up their largest telescope. 

Central to the observatory is education and its award-winning exhibitions and workshops are inspirational. Little surprise it is one of the top visitor destinations for schools and young scientists. Since it opened to the public in 2007, it has welcomed 1.3m visitors.

But will the observatory be welcoming extraterrestrial visitors anytime soon?

“We now know there are probably trillions of planets in the universe not too far away from us, within our own galaxy,” says Alan. “Many of them are not going to be habitable, but the numbers that might be seem to be increasing. There is an area called the Goldilocks Zone, where planets are the right size, the right temperature, and have the right pressure.

“These are places that are comparable to Earth. So, the likelihood there isn’t life out there seems to be decreasing.”

“There’s nothing particularly special on Earth that doesn’t happen elsewhere,” says Niall Smith. “We’re not unique in the universe, in terms of molecular interaction or the laws of gravity.

“I’ve always assumed that because the makeup of molecules on Earth is similar to other planets and our sun is similar to lots of stars, life elsewhere is at least possible.

“So, unless you assume there’s something special about us, unrelated to the laws of the universe, it’s very hard to imagine that there isn’t life out there.

“At the same time, it’s really interesting that we haven’t seen it yet. It’s a puzzle that we haven’t seen any evidence of life, but there’s no reason to believe that Earth is unique.”