
The Square Kilometre Array (SKA) Observatory has released the first images from its partially built low-frequency telescope in Australia, known as SKA-Low.
The new SKA-Low image was created using 1024 two-metre-high antennas. It shows an area of the sky that would be obscured by a person’s clenched fist held at arm’s length.
Observed at 150 MHz to 175 MHz, the image contains 85 of the brightest known galaxies in that region, each with a black hole at their centre.
“We are demonstrating that the system as a whole is working,” notes SKA Observatory director-general Phil Diamond. “As the telescopes grow, and more stations and dishes come online, we’ll see the images improve in leaps and bounds and start to realise the full power of the SKAO.”
SKA-Low will ultimately have 131 072 two-metre-high antennas that will be clumped together in arrays to act as a single instrument.
These arrays collect the relatively quiet signals from space and combine them to produce radio images of the sky with the aim of answering some of cosmology’s most enigmatic questions, including what dark matter is, how galaxies form, and if there is other life in the universe.
When the full SKA-Low gazes at the same portion of sky as captured in the image released yesterday, it will be able to observe more than 600,000 galaxies.
“The bright galaxies we can see in this image are just the tip of the iceberg,” says George Heald, lead commissioning scientist for SKA-Low. “With the full telescope we will have the sensitivity to reveal the faintest and most distant galaxies, back to the early universe when the first stars and galaxies started to form.”
‘Milestone’ achieved
SKA-Low is one of two telescopes under construction by the observatory. The other, SKA-Mid, which observes mid-frequency range, will include 197 three-storey dishes and is being built in South Africa.
The telescopes, with a combined price tag of £1bn, are projected to begin making science observations in 2028. They are being funded through a consortium of member states, including China, Germany and the UK.

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University of Cambridge astrophysicist Eloy de Lera Acedo, who is principal Investigator at his institution for the observatory’s science data processor, says the first image from SKA-Low is an “important milestone” for the project.
“It is worth remembering that these images now require a lot of work, and a lot more data to be captured with the telescope as it builds up, to reach the science quality level we all expect and hope for,” he adds.
Rob Fender, an astrophysicist at the University of Oxford, who is not directly involved in the SKA Observatory, says that the first image “hints at the enormous potential” for the array that will eventually “provide humanity’s deepest ever view of the universe at wavelengths longer than a metre”.