Friday, June 21, 2013

The Mathenge blessing

Wednesday, June 12, 2013

Africa gets closer to the stars with major telescope project

Imagine being able to explore the stars and black holes in the universe.
Imagine being able to discern which between the stars and the galaxies came first.
Now picture an African making the first discoveries of new planets and whether or not humans are the only intelligent beings in the universe.
Fast forward to 2024 and this will no longer be a figment of your imagination.
African astronomers will be better placed in making these and many more discoveries thanks to the Square Kilometre Array (SKA) telescope that is currently being installed in Australia and selected countries in Africa.
The dream is being made possible after close to a decade of lobbying by South Africa to have the world’s largest and most sensitive radio telescope brought to the continent.
The SKA is a global project, with 10 member countries, that aims to provide answers to key questions about the universe.
Countries involved include the UK, Sweden, South Africa, New Zealand, Netherlands, Italy, Germany, China, Canada and Australia.

The road has not been smooth, with many of countries that bid for the telescope doubting Africa’s capacity to implement and manage the project to completion.
“Very many people would come and say — why are you thinking of looking at the stars when Africa has real problems like poverty and diseases which need to be dealt with as a matter of urgency,” Bernie Fanaroff, the project director said in an interview.
He noted that the project is among the many opportunities provided for the continent to show leadership globally by putting into use its talents and proving wrong stereotypes that Africa can only be a follower in matters technology.
The South African team’s efforts were finally realised when the SKA organisation announced in May last year that the radio telescope would be shared between Africa and Australia, with the extensive mid-frequency dish array being constructed in South Africa while Australia would host the more compact low-frequency aperture array.
The mid-frequency array will consist of about 3,000 receptors or dishes linked together across a distance of up to 3,000km. The scattered signals from the receptors will be combined digitally to enable them produce the sharpest pictures of the sky.
The telescope will give 50 times the sensitivity and 10,000 times the survey speed of the best current day radio telescopes, in addition to using enough fiber optic cable to cover the earth twice, its backers say.
Total costs to have the radio telescope up and running by 2024 have been estimated at $2 billion, but this is subject to change dependent on the cost of materials and the global exchange rates.
Dr Fanaroff explained that the receptors would be connected to one another via fibre optic cable and also connected to a central control station in South Africa and another in Australia.

“It will be so sensitive that it will be able to detect airport radar on a planet 50 light years away,” he added.
Construction for the first phase is expected to start in 2016 and be complete by 2020. In the second phase another set of mid frequency antennas will be set up in Northern Cape province of South Africa, with stations of 40 antennae each set up in Namibia, Botswana, Kenya, Zambia, Mozambique, Ghana, Mauritius and Madagascar.
“We have already started working on remote locations to place the antennas in the other countries because they need to be protected from electronics and machines that emit radio waves and thus interfere with the radio signals coming from the universe,” explained the project manager.
Together the antennae will provide a large surface area with which astronomers can explore different parts of the universe simultaneously. Working on the same principle used by radios, the telescope will be able to pick up radio waves from the galaxies, which will then be processed by computers to form images.
“At the moment such computer technology is non-existent. We are working with computer manufacturers and we also have our own team working on a motherboard that would enable the collection and processing of large data without overheating the machines. Anything capable of producing radio waves within the sites of construction will be put in underground bunkers so as not to interfere with signals,” said Dr Fanaroff.
The biggest question among critics has been whether Africa has the human capacity to manage this project.
Astronomy has for years been viewed as a non-lucrative venture with most top performing students opting for law or medicine fields. Others view the subject as unapproachable because it involves a lot of calculations and physics.
Still, the few astronomers that the continent has managed to educate were in the past unable to secure good jobs within the continent and moved to greener pastures in the West.
At the time of initiating the bid for the SKA project in 2003 for instance, there were only 12 practising radio astronomers in southern Africa, increasing gradually to the current 60 or so.
The project has awarded 293 grants and scholarships across the continent to boost the development of skilled personnel at both graduate and postgraduate levels.
“There are a lot of opportunities with the SKA telescope not just in astronomy and astrophysics but also in areas like engineering and data management. Everything for the project is being constructed from scratch and we have since taken several students from across the continent to pursue graduate and post graduate studies in order to improve our current human capacity,” Dr Fanaroff said.
Rather than be futuristic, astronomers are establishing a pilot radio telescope with receptors built to the specifics of the SKA radio telescope under the MeerKat project, currently being implemented in the Northern Cape province of South Africa.
According to the programme director, MeerKat has provided an opportunity for global scientists to test their science and engineering skills before the construction off the SKA radio telescope.
“The 64 antennas and the whole infrastructure was strategically designed to be scalable and come 2016 they will be integrated into the mid-frequency array,” he added. Many of those involved in the construction and establishment of appropriate technological support in the MeerKat project are Africans.
South Africa has also initiated a programme to connect satellite dishes across the continent, which were formerly used for communication but have since rendered redundant by fibre optic cables. The satellites will be upgraded to radio telescopes and used in exploratory research.
 The upgrade has already began in Ghana and Mauritius, while the SKA South African team is currently holding talks with the Kenyan government to upgrade the two satellite dishes in Longonot.

The SKA project experienced its first milestone mid last month when the Royal astronomy society agreed to publish the first scientific paper based on observations using MeerKat helping to boost the study of the neutral gas emissions that existed before the first galaxies and black holes were formed.