How Do You Study Something You Cannot See?
How do you study something you cannot see? – Prof Roger Deane
Or why big data might just be the game-changer astrophysics has been waiting for
Profmed’s podcast series The Professional has been looking into how the workplace is changing in new and surprising ways. The oretical scientists, more than anyone else, work alongside the expectation that their career paths will be groundbreaking. Unpredictability literally defines their work lives.
If that sounds intriguing, meet astrophysicist Professor Roger Deane, who joined the ranks of an elite group of 200 scientists worldwide to work on a project to take humanity’s first-ever photograph of a supermassive black hole earlier this year – and succeeded.
Aged just 36, Deane is an associate professor of physics at the University of Tshwane. He grew up in Welkom in the Free State. He says, “By night Welkom has wonderful skies, beautiful views of the Milky Way, and I spent many of those evenings peering up thinking what next? What am I going to do?”
He ended up helping the world see the unseeable.
Prof Deane enrolled in electrical engineering, which his parents thought of as a more reliable career path, at UCT but added some undergraduate astronomy courses on the side. He was hooked. A Masters in astronomy came next, followed by a PhD at Oxford University. “It was halfway through my electrical engineering undergraduate degree that I started hearing about the meerkat telescope project in the Karoo,” he recalls. But more on that later.
Deane got a lucky break in 2014 and joined the ambitious international team working on the black hole imaging project.
Black holes are like teenage goths of the celestial playground – dark, moody, and quite hard to understand from the outside. We’ve been reasonably sure that they exist ever since Albert Einstein postulated them in 1916. But more than 100 years later we still had no idea what one looked like, mainly because black holes are completely dark. The fact that they hoover up light like a super-massive vacuum cleaner means that scientists can’t study them like they do stars or galaxies or the rest of the universe.
“A black hole, by definition is a region in space-time from which nothing including light can escape. It’s a one-way trap door out of the universe. So that image represents the last bit of light that is in our universe, before exiting into this black hole,” explains Deane.
To observe a black hole, scientists needed to develop a huge and complex telescope – as well as computer simulations to decide how to “drive” the telescope when the time came to take the picture.
Eight of the highest, driest, most desolate and most extreme parts of the world became sites for a giant telescope: the South Pole Station, where just 50 people remain during the bleak winter every year; the Sierra Negra in Mexico; Pico del Veleta, at the end of the highest paved road in Europe in southern Spain; Mauna Kea, a dormant volcano in Hawaii and the highest mountain in the world measured from its base; the Andes in Chile, an iceberg-studded bay in Greenland andthe enormous mountains of Arizona. “You have to be above the weather, above the water vapor in the air,” says Deane. Linked together they create one truly massive telescope, the Event Horizon Telescope. ”I think it’s appropriate that you have to go to the extremes of the earth in order to take a photograph of one of the extremes of nature, a black hole,” says Deane.
To snap this intergalactic photo took a decades-long global effort by some of our brightest minds, a two-year process to develop the image, and some technology that they had to invent along the way.
The resultant photo, a combination of innovation, knowledge, experimentation, collaboration and luck – well, it looks a bit like a blurry, neon orange doughnut. This is not surprising, since the black hole is five hundred million trillion kilometers away. It is also, however, three million times the size of the Earth. “So it’s 6.5 billion times the mass of our sun but squeezed into basically the size of our solar system, and smaller. It’s an extraordinarily large mass in an extraordinarily small region of space-time.”
Back to that meerkat. Roger’s bit of cosmic luck is that it’s a good time to be an astrophysicist in South Africa right now. The meerkat radio telescope is made up of 64 enormous dishes dotted about the Northern Cape, and it’s already taking insanely detailed and stunning images of our galaxy.
Deane is excited by the development: “You’re going to see many young South African astronomers pulling off wonderful discoveries. There is a huge group of young South Africans who are using the meerkat, who are data-savvy, and who are processing this data and making images of the universe in a way never seen before.”
One day, the meerkat will end up feeding into the world’s biggest-ever radio telescope. It’s called the Square Kilometre Array (SKA), and when that’s completed, it’s going to be able to pick up even more detail than the event horizon telescope. “When the SKA starts spitting out masses of data and images of its own, we’re going to have to find new ways of processing it,” says Deane.
“Astronomy has a big data problem, but I see it as an opportunity to make ourselves even more relevant to day-to-day technology. By training students to process this data, they are building up transferrable skills, so that they can go into any field that poses the same kinds of challenges.”
There’s an economic argument for learning how to manage big data: “Astronomy is a high-tech discipline. It requires us being on the bleeding edge of the fourth industrial revolution, to deal with big data in a smart way. In a few years’ time, for example, the data from SKA will have larger archives than Facebook and Google combined.”
“When you use your phone, you’re on Wi Fi that came from radio astronomy. The technology will open up billion- and trillion-dollar industries down the line.”
Deane thinks this gigantic project is good for the country – and the world.
“Most of the technology we’ll need to keep up with the data that the SKA spits out hasn’t been invented yet.
Just like Deane couldn’t imagine what he’d be doing now when he was still in school, children today are going to be working on things we don’t even know about yet. And that means young people need to think differently about their careers.
“Don’t just think about going for a specific degree to get a specific job. Think about the kinds of skills you want to develop in the 21st century, in an era when things are changing so dramatically, particularly artificial intelligence, machine learning, and the opportunities those bring.”
“I think astronomy has a way of inspiring people to think a little more laterally and be a bit braver in that regard.”
What’s possible when we stand on the shoulders of giants, and build on the knowledge we’ve gained so far, all the way from Galileo to Albert Einstein and beyond?
“Are we alone in the universe? A young astronomer can get involved in that immediately. We know of that question. But what really fascinates me is the questions we haven’t yet asked, because we haven’t made the discoveries that enable us to ask the following question,” says Deane.
“There are questions that are fundamental to our understanding of the universe, to our places, humans in the universe. But then there are questions that will only come about following the kinds of discoveries that a telescope like meerkat will make.”
And those are the ones he’s hoping the next generation of scientists, astronomers and data crunchers will ask and answer – right here in South Africa.