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and radiation 14 billion years ago, but soon cooled down and

nology” customer base, to be a part of this awesome science

was dark for hundreds of millions of years, before any stars

instrument.

formed. Nobody yet knows when these stars formed. Today’s

“We have local contractors installing our main support poles,

announcement increases the chances that signs of the first

cutting our structural elements to size, and making up our re-

stars and galaxies ever to be created will soon be detected –

flector surface panels from bulk supplied material. Similarly, for

in South Africa’s Northern Cape,” explained SKA South Africa

our construction crew in the prototype phase, we assembled a

Chief Scientist, Dr Fernando Camilo.

team of local young people who have taken on the construc-

The potential to transform knowledge Four hundred thousand years after the Big Bang, the Universe

tion and made it their own," said Rosie. Two SKA South Africa interns who were part of the fibretraining programme in 2015 are part of the team of four.

was largely made up of neutral hydrogen, the simplest and

“They have rapidly developed into very capable HERA build-

most common element. Eventually, while the Universe at large

ers who can hold their own with everything from land survey

expanded, ever-larger clouds of hydrogen gathered due to

equipment to general construction and the maintenance of

their mutual gravitational attraction. In time, some of these

the front-end signal chain of a radio telescope,” added Rosie.

clouds became dense and hot enough that hydrogen atoms fused and the first stars formed.

A global partnership

These first brilliant objects flooded the Universe with ul-

The University of California, Berkeley, leads the experiment in

traviolet light that split or ionised all the hydrogen atoms

collaboration with partner teams from the USA, UK, Italy and

between galaxies into protons and electrons – the beginning

South Africa. Participating South African institutions include

of cosmic reionisation.

Rhodes University, the University of KwaZulu-Natal, the Univer-

“HERA, which operates at low radio frequency, has enough sensitivity to detect cosmic reionisation and we hope to map

sity of the Western Cape, the University of the Witwatersrand and SKA South Africa.

it very precisely by statistically measuring how the fraction

Connecting HERA to MeerKAT, Dr Rob Adam, SKA South Af-

of neutral hydrogen changed with cosmic time. HERA has

rica Managing Director, said that “among other investigations,

the potential to transform our knowledge in one of the main

MeerKAT will study evolved galaxies in the later Universe, while

SKA science areas,” said SKA South Africa Senior Astronomer,

HERA will peer back nearer to the dawn of time, when the first

Dr Gianni Bernardi.

stars and galaxies were being formed. In this way they address

The work is all the more impressive because the telescope’s

complementary scientific questions”.

minimalist design makes it a relatively inexpensive structure.

“This shows that the site selection for SKA South Africa was

As each antenna will point in a fixed direction, they do not

of such a good standard that we attract more international

have to move around, so no expensive moving parts are re-

funding to South Africa and the site is a host for other scientific

quired.

instruments,” he added. Over the next decade, MeerKAT will become integrated into

Proudly Karoo-based

SKA1-MID, Southern Africa’s portion of the largest astronomical

Project Engineer Kathryn Rosie, who is responsible for HERA’s

project of all time, the SKA.

construction in the Karoo, described HERA as a truly Karoobased instrument. “Construction materials are sourced and fabricated from

This will be complemented by SKA1-LOW to be built in Australia, which in turn will study in much greater detail the pioneering detections expected from HERA.

within South Africa, predominantly from the Carnarvon area.

HERA is one of a number of low frequency telescopes, includ-

Because the bulk materials of construction are light industry

ing the Murchison Widefield Array in Australia and the LOw

materials such as wood and PVC pipe, there is opportunity for

Frequency ARray in the Netherlands that are pathfinders for

local businesses, which don't necessarily have a “high tech-

SKA1-LOW to be located in Australia.

Public Sector Manager • December 2016 / January 2017

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PSM December/January Edition 2016/2017