Johannesburg - When students and post-doctoral fellows met in Stellenbosch to discuss their particular research interest this week, the chances of one or more of them in that group earning a Nobel Prize some time in the future were significantly better than for most other gatherings of that kind.
Or perhaps one of them might turn out to be a new Steve Wozniak (the computing genius behind Apple) who will start a new global computer company that’s a leader in the field in collecting, processing and storing “big data” sets thousands of times the size that can be handled by current computing capabilities.
This is because these young researchers are working on aspects relevant to the international Square Kilometre Array (SKA) radio telescope project that is set to radically change the face of physics and astronomy during their lifetimes.
Professor Phil Diamond, director-general of the UK-based multi-national SKA Organisation that is managing this mega-project, told them: “It truly is an exciting time to be in astronomy. As young scientists, you’re going to be looking at some amazing facilities that are being made available to you over the coming years. I think what you’re going to see in the next couple of decades is transformation in science and astronomy.”
These students have received bursaries through SKA Africa’s human development programme and were meeting for the annual week-long conference of its kind where they’re given an opportunity to present their research work related to the SKA that they’re doing at their respective universities and institutions.
And they are described collectively as “the future of the SKA programme”.
In his opening address, Diamond told them the SKA would be one of four great “cornerstone” observatories for the coming decades. These new observatories are:
n The E-ELT, or European Extremely Large Telescope, a revolutionary new ground-based telescope in Chile that will have a “monster” 39-metre main mirror and will be the largest optical/near-infrared wavelength telescope in the world. Construction is due to start soon on this E1 billion facility;
n The Atacama Large Millimeter/sub-Millimeter Array (Alma), an astronomical interferometer or array, of radio telescopes in the Atacama desert of northern Chile. Costing about $1.2 billion, this “fantastic instrument” is the most expensive ground-based telescope in operation. Alma began scientific observations in the second half of 2011 and has been fully operational since March;
n The James Webb Space Telescope, due for launch in 2018, a big Nasa project with contributions from many other countries. It will be the leading deep infrared telescope of the future; and
n The SKA, which will be the most powerful of all and the biggest scientific instrument in the world.
“So why do we want to build the SKA? Well, what we want to do is to really understand the universe,” Diamond explained.
After the Big Bang at the start of the universe some 13.8 billion years ago, there was a period of about 400 million years known as the cosmic Dark Ages. Then, during the following period that astronomers call the the Epoch of Reionization, the first stars were born and then galaxies started to form from the agglomeration of these early stars. The Solar System, of which Earth is a part, was only formed about nine billion years after the Big Bang.
“So a good part of the universe had happened before our Solar System even came into existence,” Diamond continued.
“We humans appear as a very microscopically thin line (at the end of a pictorial representation of the history of the universe).
“So in the scale of the cosmos and the scale of the universe, we are fairly insignificant!
“But what we’re trying to do is understand the physics of the whole universe and how it got to where it is now. I think it’s fair to say that in the 20th century we discovered our place in the universe, and in the 21st century we want to understand the universe that we inhabit. So the SKA is going to enable us to probe some fundamental physics.”
These included investigating and trying to fully understand gravity, electromagnetism and the strong nuclear force – three of the four “fundamental forces” of the universe that physicists have identified. (The fourth is weak nuclear.)
“We also want to understand origins – the origins of galaxies, of stars, planets and life,” Diamond continued.
“We want to study biomolecules and perhaps even find that enigmatic and elusive signal from other civilisations with similar technological capabilities as ours.”
The theory of gravity still needed testing, he added.
“The classical tests have been done in the last century and general relativity (Einstein’s theory) has been shown to explain them. There are also more modern tests using spacecraft that also demonstrate that general relativity is the preferred theory of gravity. “But there’s a problem: ‘precision cosmology’, as it’s called nowadays, has uncovered that the universe is accelerating, that the mysterious dark energy is pushing galaxies further apart faster and faster.”
Dark matter dominated the space between galaxies but scientists still had no idea of what this dark matter was. “So there are huge mysteries out there, and the theory of gravity is required to explain some of these mysteries. It’s possible that general relativity is the correct (theory), but we don’t know. We need to test it in extreme environments and we cannot generate such an extreme laboratory on Earth.”
So the study of other objects in the universe was needed to satisfy these research requirements, and the SKA could provide access to these objects.
Another key goal of the SKA was to probe the Dark Ages, Diamond said. This would be done by studying the history of hydrogen, the most common element in the universe, in different epochs.
“So as well as being a physics machine, the SKA will also be a time machine looking back in time using hydrogen. “If we can use the SKA to detect, observe and understand the physics of the early universe, I think that will be a fantastic goal, and it’s one of the key science projects of the SKA.”
But the giant new radio telescope was also being designed as a “general purpose facility”.
“ We want to be able to find those unknown phenomena that will emerge from building a facility that, as well as undertaking key science, will also discover unexpected things, and radio astronomy has a huge history of discovering unexpected things.
“The sensitivity and the huge field of view of the SKA will be two big changes that will enable us to look for new and different phenomena, so who knows what we’ll find?”
The massive SKA project was highly complex but achievable, and it was keeping to the set time-scale.
Construction was due to start from the end of 2017 and would run until 2023, with early science starting in 2020, Diamond said.
“We (now) have a three-year design process in front of us which is a very exciting roller-coaster ride, but it will deliver the SKA. “We do have challenges but we can’t be afraid of them. They’re hard, but just because things are hard doesn’t mean we shouldn’t attempt them. And the fact that we have so many people engaged in the SKA is wonderful, and certainly bringing in young people because they’re not afraid, and we shouldn’t be either.” - The Sunday Independent