The Bursting Sky: Staying Up For The Cosmic Dawn

Five years from now, the most powerful radio telescope in the world will be fully operational across two continents—detecting faint signals humming the secrets of our universe. 

In the last three decades, an eight-country effort planned the The Square Kilometre Array Observatory (SKAO), with mid-frequency telescopes located in South Africa and low-frequency telescopes in Australia. Overall, 16 countries were involved in making the effort possible. The project’s headquarters will be based in the United Kingdom. 

Scientifically, the SKA telescopes will be able to detect the most minute and faint signals yet, something that will be a “huge step forward” for astronomers, Dr. Shari Breen, the project’s science operations leader told States of Life. Breen got involved with the SKA effort by working with the project’s precursor instruments. 

Astronomers from all over the world have been anticipating their arrival for more than a decade now, already designing the experiments they want to use the telescopes for,” Breen said. “What is truly exciting is the breadth of science that the SKA will be able to do.”

Artist impressions taken from animations of the SKA-Mid telescope in South Africa (Image courtesy SKAO)

That flexibility will only aid the project’s overall scientific mission, and its objectives are stunning. The project’s science drivers are grouped into several goals: 

“The most exciting science areas will be those that drew me to radio astronomy in the first place,” Breen said. ‘How do stars form?’ We have a pretty good idea but we certainly don’t have a clear picture across the full spectrum of star masses that we see. Stars are the building blocks of galaxies and are incredibly important to many areas of astronomy.”

Along with peering deep into the cosmos, SKA telescopes will reveal secrets of our own cosmic neighborhood. 

“We don’t know some of the basic details of the structure of our own galaxy given the floods of beautiful images from telescopes such as the Hubble and James Webb,” Breen said. “If only we could take a picture of the thing that we live in.” 

Other tasks include studying the history of hydrogen, the most abundant element in the universe. By tracing hydrogen’s history, Breen said the project can “trace the history of how the universe came to be.” 

In order to listen for answers from such a daunting cosmological playlist, the telescopes in South Africa and Australia are being built in vastly remote areas, avoiding civilization to detect very weak signals from space.

Pictured is an advisory sign for one of the SKA quiet zone areas already in use for radio astronomy in Australia. (Image courtesy of SKAO)

The SKA telescopes’ locations, combined with their sheer scale as well as the clever engineering and design, will make them the best in the world,” Breen said. Construction on the project started in 2022 and is expected to be completed in 2028. But it won’t take long for astronomers to start conducting science towards those lofty objectives. 

“The first results of note can be expected when we have reached the third construction milestone when half of SKA-Low’s antenna stations and 133 of SKA-Mid’s dishes come online,” Breen said— and it’s then the mission will already exceed the capabilities of any current telescope array. 

The low-range telescopes in Australia will detect between 50 and 250 MHz, and consist of more than 130,000 antennas grouped into 512 field stations, with the furthest stations being 74 km (45.98 mi) apart. The mid-range telescopes will detect 350 MHz to 15.4GHz and consist of 200 parabolic dishes, most of them being six stories high and 15 m (49.21 ft) in diameter and the furthest stations 150 km (93.21 mi) apart.

Artist impressions of the SKA-Low Frequency Stations in Australia. (Image courtesy of SKAO and DSIR)

States of Life: If you could travel anywhere in our universe, where would you go and why? 

Breen: While I love studying our galaxy and its place in the universe, I am quite intimidated by the vastness of space and the varying gravitational conditions! I prefer to see the majesty of the universe through radio images with my feet firmly on the ground.

Dr. Shari Breen holds a Ph. D. in radio astronomy from the University of Tasmania in Australia. Her specialism is studying how the largest stars in the Milky Way galaxy form. She does so by observing masers as they arise naturally in the vicinity of younger stars, and by studying the detailed maps of the gas across our galaxy. Her journey into astronomy started when she joined the Astronomy and Space Science Division of the CSIRO, Australia’s national scientific agency as a Bolton fellow. From there, she moved to the University of Sydney and got involved with the SKA project. 

Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s