Two steps closer to SKA

SA has made two significant advancements in its bid to host the Square Kilometre Array (SKA) telescope.

The Department of Science and Technology (DST) says breakthroughs were made in computing speed and capacity in astronomy.

It adds that these achievements give momentum to SA's bid for the SKA, which will provide detailed pictures of the “dark ages” 13.7 billion years back in time, for the first time.

The DST says an important milestone was reached with the “detection of fringes” in a joint very long baseline interferometry (VLBI) observation. SA completed this experiment without assistance from other countries for the first time.

“The 26m Hartebeesthoek Radio Astronomy Observatory near Pretoria teamed up with one of the seven 12m dishes currently part of the Karoo Array Telescope (KAT-7), over 900km away, to jointly observe and record data from a distant radio source.”

The department adds that the data was then correlated in Cape Town to produce the first ever African fringe detection at its first attempt.

“VLBI is significant as it's used for imaging distant cosmic radio sources, spacecraft tracking, and for applications in astrometry. However, it can also be used 'in reverse' to perform earth rotation studies,” says SKA SA project director Bernie Fanaroff.

In addition to the fringe detection breakthrough, South African engineers have built the building block for the next generation of digital processing systems, according to the department.

“The reconfigurable open architecture computing hardware (ROACH) board is primarily a South African development and already in use in 300 hi-tech facilities around the globe. However, ROACH-2 prototypes are much faster and more powerful.”

“This is all essential preparation for the SKA project,” says Fanaroff.

He explains that the need for such computing speed and capacity in astronomy arises with the expectation that the SKA will collect more data in one week than humankind has collected in its entire history.

“SKA will revolutionise science. It will be the world's largest radio telescope and probably capable of answering questions that we haven't even thought to ask yet,” says Fanaroff.

The department adds that expected scientific discoveries include understanding the cosmic web of neutral gas, which will unravel how the first stars and black holes were formed.

“It will track galaxies to investigate the rate of expansion of the universe and hopefully identify the nature of dark energy. It will also produce three-dimensional galactic maps and detect what are likely to be extremely weak extra-terrestrial signals and pinpoint planets capable of supporting life. It will also allow for the study of gravity, which could possibly lead to the theory of relativity being challenged.”

A previous concern for SA's bid against Australia was SA's relatively high bandwidth costs in conjunction with the SKA's large bandwidth requirement.

However, Fanaroff says: “In 2011, SA - in conjunction with its eight African-partner countries bidding communally for the SKA - will pull out all the stops to show the world that Africa is the future as far as science and technology are concerned.”

The final decision regarding the successful host country for the SKA telescope is expected in 2012, with work due to start in 2013. Operations will start in 2015, provided a significant portion of the array has been commissioned.

The SKA is a mega telescope, about 100 times more sensitive than the biggest existing radio telescope.