It’s said to be the most important discovery in astronomy in a generation. And, if it’s confirmed, it will herald the start of a whole new era in physics, and of our understanding of our place in the cosmos.
The detection, this week, of gravitational waves, draws back the curtain on that most elusive of questions: where did we all come from?
Formed in the first trillionths of a second after the big bang, the waves show the very beginning of the laws of physics: the creation of the stuff that made us. They’re the smoking gun.
“Detecting gravitational waves is hugely important to drive our understanding of the cosmos forward,” says Dr Chris Copperwheat, of Liverpool John Moores University (pic) – the only UK university with its own research telescope – a 2 meter-wide lens high on a hill in La Palma, Canary Islands.
For the past ten years, it’s been cataloguing some of the most cataclysmic events ever observed – building a clearer picture of the universe’s very earliest times.
But, over the coming decade, Liverpool hopes to be at the forefront of gravitational wave dectection – ripples in the curvature of spacetime which will open up a whole new eye on astronomy.
“These waves are the only part of Einstein’s theory of relativity that’s yet to be proven,” Copperwheat explains, “and if this discovery is confirmed, it will fundamentally alter our understanding of how the universe was formed.”
Because these waves – set in motion at the very beginning of space and time – penetrate regions of space that electromagnetic waves can’t reach, astronomers believe they’ll provide observers on Earth with information about black holes and other, as yet unknown classes of objects in the furthest reaches of the known Universe.
“We can’t observe the waves themselves with optical telescopes, but as they are discovered, we’ll be able to track the waves back to whatever object first made them, and who knows what we’ll find there. Every time we’ve found a new way of observing things, we’ve always discovered something amazing,” Copperwheat says.
What gravitational waves offer, Copperwheat says, is the chance to detect things that telescopes would otherwise miss because the light is so faint. Peer any further back in time than 300,000 years after the big bang, and light ceases to exist. But find a gravitational wave, and you can surf it back to almost the big bang itself.
The detection, announced yesterday at the Harvard-Smithsonian Center for Astrophysics in Cambridge, Massachusetts, comes from the work of telescopes at the South Pole. But Liverpool’s scope is a recognised leader in searching out the most elusive events at the outer reaches of the known universe.
“The expertise that’s built up with the first telescope is immense,” says Project Scientist, Dr Chris Copperwheat, one of a team of 60 delving into the depths of space, next door to the Tesco Express.
“It’s much more common for US universities to have their own telescopes, but it’s a testament to the University, who recognised that robic operations meant we could operate a scope without a ground team over there,” Copperwheat explains.
All of which means that, while the scope might be basking in the Canaries, it’s actually operated in the breezy environs of Brownlow Hill – making the scope easily available to research bodies (and schools) across the UK, and Spain too.
Now the University’s set its sights on a replacement – the huge LT2 Telescope – a massive 4 metre scope which, when operational in ten years’ time, will be the world’s biggest remotely operated robotic scope (Liverpool’s current model is the world’s biggest, now, so we’ll be in positions 1 and 2 by the middle of the next decade).
Because of their agility and speed (robotic scopes can align themselves to any point in the sky much quicker than manually operated ones) Liverpool’s at the forefront of observations requiring split-second observations of some of the cosmos’ most fleeting – and most interesting – events.
Copperwheat’s current research is based around neutron stars at the very edge of the known universe, and of sudden, violent explosions of gamma ray bursts – the last, cataclysmic hurrah of dying stars.
“The earlier you get onto these the better, and our telescope gets there earlier than any others. We’re the fastest in the world. Everyone else is in our dust,” Copperwheat says. And, keen to explain why it’s not just a speed thing – that there is, like, science behind it, he adds:
“The earlier you can observe extreme environments, the better you’re able to understand what was there before it went bang,” he says. “Ours is one of the few telescopes that focus on this area.”
Gamma ray bursts are the most energetic explosions in the universe. As astronomers probe closer to that explosion, they’re inching closer to an extreme state of physics. Closer to the most fundamental questions of all.
“This is the most exciting aspect of cosmology – you’re pushing back further and further, to the most earliest times – the difficulty is there is the further you look back, you reach a point where the universe becomes optically black. Then you simply can’t see anything.”
And, Copperwheat says, when it comes onstream, the next telescope will be even faster still. Who knows what secrets that’ll unlock?
“We look at the universe and, philosophically, we think it’s this vast, stately firmament. But everything’s changing and evolving in microseconds. And time-sensitive observations are where the Liverpool telescope is world beating. We’re a real discovery engine.”
Slightly closer to home, Copperwheat and his team are also on the hunt for exoplanets: planets orbiting stars many light years away from our own sun. Planets that might harbour life.
“Our telescope is excellent at this,” he says, explaining how variations in a star’s ‘wobble’ or or the slight dimming of its light are telltale signs that you’ve found another solar system.
“People have even discovered water in these planets, that’s how good our observations have become. In ten, twenty years time we’ll be looking for oxygen, signs of pollution and signs of life. It’s an incredible area of astronomy,” he says, “ but it also speaks to us very philosophically, too.”
The idea of discovery, of finding something new, is what keeps Copperwheat and his team devising new experiments, finding new ways to keep the telescope turning.
“I’ve discovered new binary star systems,” he says, “and to be the only person in the world that’s spotted a new part of the universe is an amazing feeling. Doing this job, you realise how little you know. Even fundamental stuff, like how far away nearby galaxies and stars are.”
Until fairly recently, the search for extraterrestrial life has been, Copperwheat says, scattergun – slicing and dicing radio signals to listen out for unusual patterns in the noise. Now, with optical telescopes getting ever more powerful, we’re able to hunt for planets in the ‘sweet spot’ – just close enough to their star to allow for water to flow.
“As we move forward, we can take a much more targeted approach,” Copperwheat says. “Observations like ours give us more information than ever before to tell us where to look. We’re now finding earth sized planets in the habitable zone. That means there’s a very real possibility that a discovery of an exoplanet with life will be made in our lifetime…”
And a very real possibility that these signs of life will be spotted, first, by Chris and his team, peering into the depths of space, in the shadow of the Metropolitan Cathedral.
“Gravitational waves are a new frontier in astrophysics,” Copperwheat says, “They tell us how the universe – and how we – came to exist.”
All pics © The Liverpool Telescope