Scientists from South Africa are playing a leading role in developing the science which will be done with the world’s largest telescope, the Square Kilometre Array.
The SKA telescope, to be built in Australia and South Africa, will allow scientists to look far back into the history of the universe and will give much more detail than before on how the universe has evolved over 14 thousand million years. More information will be obtained on how stars, galaxies and clusters of galaxies formed and how they have changed since the Universe was young. This will allow for the plotting of a 3D map of the Universe.
The international SKA Organisation, which includes eleven countries, is bringing up to date the science case for the telescope. South African scientists are playing a leading role in many of the working groups. The SKA Cosmology Working Group is chaired by Roy Maartens, SKA Research Professor at the University of the Western Cape (UWC). Professor Maartens and Professor Mario Santos, also a Research Professor at UWC, with astronomers from South Africa and the other SKA member countries, have played a leading role in setting out the SKA science.
Roy Maartens says: “Researchers here have devised a means of using the world’s largest telescope in new ways that will help shape the future of cosmology.”
Mario Santos says: “Usually a map of the Universe is made using galaxies as tiny beacons of the large scale structure of the Universe. This is quite demanding as it requires the mapping of large numbers of galaxies across the sky.”
“The survey we are proposing will measure the emitted radiation from all the hydrogen atoms spread across the Universe without actually detecting galaxies. This will make it easier to survey all of the sky across cosmic times, allowing the phase 1 of the SKA to become an extremely competitive cosmology machine,” he adds.
“By making these huge, 3D maps of the Universe we will be able to test the limits of General Relativity and maybe find some signature of new physics on these large scales which can shed light on the true nature of dark energy. Moreover, we can also look for imprints of what happened at the very beginning of the Universe,” added Santos.
An experiment like this, says Santos, using intensity mapping, has never been done before. The largest 3D maps of the large scale structure of the Universe have been done using optical telescopes. The current project will be about 50 times larger. Other future experiments, such as the Euclid satellite, will be able to also probe a large fraction of the Universe, but none will match the SKA in terms of size and depth.
Maartens adds: “It will be like making a movie of the Universe from a young age, when it was only about 2 billion years old, until today when it is about 14 billion years old. The movie will be low resolution but enough to test the fundamentals of cosmology.”
When the actual survey with the SKA comes online, a large team will be required to deal with it. Once the phase 1 of the SKA is built, around 2023, it will take about 2 years to complete the survey.
SKA SA has been crucial in promoting the build up of the required researchers to lead such an effort. However, says Santos, they don’t have to wait for the SKA to start, before doing observations. “Tests are already being conducted using the KAT7 system with the full support of the KAT7 staff and we plan to start tests with MeerKAT in just a year, during the early science phase,” Santos stated.
He added that the SKA telescope is like a “physics lab”, allowing many different experiments to be pursued. There will be other surveys that in combination with this one, will allow scientists to push the limits of our current knowledge of the Universe.
Shared Sky stems from a vision by the Square Kilometre Array (SKA) Organisation to bring together, South African and Australian artists in a collaborative exhibition celebrating humanity’s ancient cultural wisdom. This vision embodies the spirit of the international science and engineering collaboration that is the SKA project itself, bringing together many nations around two sites in South Africa and Australia, to study the same sky.
Shared Sky connects artists working in remote communities from either side of the Indian Ocean that have ancient cultural connections to the two sites where the SKA will be located. Both locations were specifically chosen for their radio-quietness and relative isolation – fundamental requirements for a successful radio telescope facility. Prototype ‘precursor’ telescopes are already active at each location, some of which will eventually become part of the much larger SKA telescope – the world’s largest-ever radio telescope.
Through this global collaboration involving governments, scientists and engineers from over 20 nations, the SKA radio telescope will capture unprecendented levels of information, often from the farthest reaches of the Universe. By enabling scientists to see deeper into space, further back in time, and with greater clarity than has been possible, the SKA will greatly enhance humanity’s knowledge of the Universe.
The exhibition reflects an understanding of the world that has been developed across countless generations observing the movements of the night sky. Minister Pandor says of the exhibition: “While Shared Sky successfully reflects on the ancestral interpretations of the night sky from indigenous people from both South Africa and Australia, it also touches on South Arica’s flagship science programmes. South Africa has a rich fossil heritage, allowing for world class research in human origins. At the same time, we host top astronomers exploring our place in the universe.”
Being located on similar latitudes on both continents, the two sites in Australia and South Africa present essentially identical views of the night sky to the people who have lived there for tens of thousands of years, and to whom some of the oldest known artwork on earth can be attributed. Shared Sky explores how this understanding resonates in the work of living artists that are sharing their insights with scientists working to unlock the secrets of the Universe.
Shared Sky also embodies the idea that no borders exist in the sky and that the night sky is an increasingly scarce natural resource that belongs to and is shared by all humanity.
The movement of objects across the night sky has been a profound source of inspiration for the artists since time immemorial. The desire to understand this has informed creation myths and stories among human populations across the globe for countless generations.
It is what has inspired both groups of artists in this exhibition, and what drives the large international teams of scientists and engineers developing one of the world’s greatest scientific endeavours in Australia and South Africa: the SKA
In South Africa, artists who are descendants of |xam speaking San people and others of the central Karoo work communally to produce artworks at the First People Centre of the Bethesda Arts Centre in the small village of Nieu Bethesda, Eastern Cape. They have produced collaborative artworks in textiles that explore their own creation myths and celebrate the ancient culture of their ancestors that survived in the harsh environment of the central Karoo desert region for millennia. These large art tapestries reflect a visual language that stretches back to a time of great antiquity. Fragments of ostrich eggs between 65-75,000 years old have been found which show evidence of decorative engraving, a distant connection to the lost art of rock engraving so evident across South Africa’s central Karoo region. Art forms like these flourished from the end of the last ice-age approximately 12,000 years ago. The story-telling traditions of these artists’ forbears would have remained largely a mystery if it were not for the comprehensive archive of the Bleek & Lloyd Collections. It comprises verbatim interview accounts of hundreds of traditional |xam stories translated into English. Although little evidence exists of the specific purpose of the rock engravings and paintings that are still in situ in the Karoo, they do afford tantalising glimpses of the culturally specific ritual significance of this extinct petroglyphic practice.
For Yamaji people – indeed many Aboriginal communites right across southern Australia – the appearance of the dark shape of an emu stretched out along the length of the Milky Way has heralded the season for collecting emu eggs for thousands of years. In Western Australia, the Yamaji and other Aboriginal artists who have created artworks for Shared Sky are descendants of, or connected to, Wajarri people that until the mid-19th century were still living a largely traditional way of life, hunting and gathering on the land that is now the site of the Australian SKA. The Yamaji Art Centre in Geraldton, Western Australia is a community arts organisation and strong advocate for social justice and the promotion of respect and awareness of Yamaji culture. It is through the auspices of the Yamaji Art Centre that the artists have connected to Shared Sky and visited the Australian SKA site, spending time talking to the scientists and, under the stars, sharing their stories about the night sky. Though most have not lived on this specific land, they create artwork throughout the Mid West region to promote their culture and continue the process of teaching their own communities the stories of their ancestors, reviving dying languages and nurturing Aboriginal culture to maintain connections to their traditional Country.
The resilience of culture
Shared Sky presents an unprecedented opportunity for these peoples, who share so much through their common colonial histories, to reflect upon the countless generations of proud custodianship of their respective homelands and draw strength and inspiration from each other. That these communities developed such rich and distinctive cultures over thousands of generations in absolute isolation – and an entire Indian Ocean apart – yet share so many deep concerns for the preservation of their cultural heritage, is fitting testament to the power of collaboration. Stories passed on through meticulous oral traditions from one generation to another across the millennia, and the profoundly complex understanding of celestial mechanics common to both cultures, has been brought together in this way through the cultural agency of the Square Kilometre Array project and the willingness of scientists to reach out and appreciate alternative ways of seeing.
Shared Sky is brought to you by the international Square Kilometre Array (SKA) Organisation, Manchester, UK; SKA South Africa, Johannesburg, South Africa; SKA Australia, Canberra, Australia in collaboration with Curtin University’s Institute of Radio Astronomy.
Shared Sky was developed in collaboration with Yamaji Art Centre, Geraldton, Western Australia and the First People Centre at the Bethesda Arts Centre, Nieu Bethesda, Eastern Cape, South Africa.
Shared Sky is hosted by Iziko Museums of South Africa, a national flagship institution and an agency of the national Department of Arts and Culture, at the Iziko South African National Gallery.
Shared Sky has been curated by Chris Malcolm, Director, John Curtin Gallery, Curtin University, Perth, Australia, as international currator in partnership with John Parkington, Emeritus Professor of Archaeology, University of Cape Town. Shared Sky is presented in South Africa in collaboration with curator Sandra Prosalendis, exhibition designer Elsabe Gelderblom and Carol Kaufmann, Curator of African Art at the Iziko South African National Gallery, Cape Town. The Shared Sky exhibition will be open to the public from the 06th of February till the end of May 2015.Shared Sky will be officially opened by the Minister of Science and Technology, Naledi Pandor, on the 13th of February 2015.
SKA SA-supported PhD and MSc students, postdoctoral fellows and senior local and international researchers met in Stellenbosch for the ninth SKA SA postgraduate bursary conference, from 4 to 8 December.
At the first postgraduate bursary conference, which took place in 2006, there were less than 50 delegates in attendance, of who only about 15 were students. In 2014, more than 90 postgraduate students and postdoctoral fellows gave talks on their research, and 30 more presented their research on posters.
Dr Rick Perley, from the National Radio Astronomy Observatory in the US, said he had never been to a conference at which more than 100 talks and posters were presented by students. Dr Perley, a radio astronomer of more than 30 years, was inspired by the enthusiasm and energy of the MeerKAT / SKA community in South Africa, and the significant growth in radio astronomy on the African continent, in such a short time.
At the prize-giving event, which acknowledges the best students’ presentations and posters, Dr. Matt Jarvis, from Oxford University, said that he wished his students in the UK could present talks at the same high standard he had seen at the 2014 postgraduate bursary conference. This is a comment repeated every year by the international guests who attend the conference
The number of young scientists and engineers supported by the project’s capacity development programme is testament to the significant investment by the Department of Science and Technology into astronomy, and their recognition that astronomy can contribute to driving the creation of SET capacity and skills required to enhance any knowledge-based economy.
The Minister for Science and Technology of South Africa and the President of the Max-Planck-Society (MPG) today announced that the MPG and the Max-Planck-Institute for Radio Astronomy (MPIfR) in Bonn will make available a total of €11 million (approximately R150 million) to build and install radio receivers on the South African MeerKAT radio telescope.
The receivers will be built by the MPIfR and will operate in the S band of radio frequencies. They will be used primarily for research on pulsars, the rapid spinning neutron star which emit very regular radio pulses and so can be used as highly accurate clocks to test extreme physics. Two other sets of receivers, for the L band and ULF band of frequencies, are already under construction in South Africa.
The President of the MPG, Martin Stratmann, said: “We consider MeerKAT to be an important undertaking as it is not only a preeminent astronomy project, but also a light-house project for science in Africa in general. The MPG is very pleased to enable close collaboration between its scientists and the South African community and looks forward to see MeerKAT’s first glimpse of the Universe with the receivers of the MPIfR”.
Welcoming the strong and growing collaboration between South Africa and Germany, Minister of Science and Technology, Naledi Pandor said that the investment is an endorsement of the excellence of the MeerKAT and the South African team which designed and is building it. Minister Pandor added that “this significant investment by a leading global research organisation of prestigious repute, home to several Nobel Prize winners, was an important vote of confidence, in South African science in general and the MeerKAT specifically.” South Africa and Germany have a vibrant science and technology partnership, with radio astronomy fast becoming a blossoming flagship area of cooperation, evidence by huge interest in academic and industrial cooperation from both sides. Minister Pandor concluded, “MeerKAT is already acclaimed internationally as a world-class instrument“ thanks to our partnership with Max Planck, MeerKAT’s ability to perform transformational science for the benefit of global knowledge production will be considerably boosted. Awaiting the start of construction of the SKA, South Africa and our international partners such as Max Planck, continue to set the pace for global radio astronomy.”
MeerKAT will be the most sensitive cm wave radio telescope in the world until the SKA is built. It is expected to do transformational science on pulsars and other areas of astronomy.