SKA-Low's first image of the universe released

The first image from the international SKA Observatory’s (SKAO) telescope in remote Western Australia, SKA-Low, has been released, marking a significant milestone in its quest to reveal an unparalleled view of our universe. The image comes from an early working version of the telescope, using just 1024 of the planned 131,072 antennas, and is an indication of the scientific revelations that will be possible with the world’s most powerful radio observatory.

SKA-Low is one of two telescopes under construction by SKAO, the other being SKA-Mid in South Africa. These are arrays that combine the data captured by individual antennas spread over large distances, working together as one big telescope. The telescopes are being constructed in stages, with components coming from SKAO member countries around the world. SKA-Low, which is being built in collaboration with CSIRO, will scale significantly to become the world’s largest low-frequency radio telescope within the next two years, partway through construction.

The new image shows an area of sky of about 25 square degrees — equivalent to approximately 100 full moons. Visible are around 85 of the brightest known galaxies in that region, all of which contain supermassive black holes. When complete, the same area of sky will reveal much more — scientists calculate the telescope will be sensitive enough to show more than 600,000 galaxies in the same frame.

The image was produced using data collected from the first four connected SKA-Low stations, which together comprise the first 1024 of SKA-Low’s 2 m-tall metal antennas. They were installed over the past year at Inyarrimanha Ilgari Bundara, the CSIRO Murchison Radio-astronomy Observatory on Wajarri Yamaji Country, and account for less than 1% of the full telescope.

SKA-Low Lead Commissioning Scientist Dr George Heald said he was delighted to see how well the first four stations were working together, stating, “The quality of this image was even beyond what we hoped for using such an early version of the telescope.”

Heald continued, “The bright galaxies we can see in this image are just the tip of the iceberg. 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. This is technically difficult work and the first step to unlocking the awesome science that will be possible.”

SKA-Low Telescope Director Dr Sarah Pearce said it has taken engineers, astronomers and computer scientists decades to get to this point, working together across teams, organisations and continents.

“It’s amazing to see all this work come together to give our first glimpse of the brilliant images that will come from SKA-Low, promising us a view of the universe we’ve never seen before,” she said.

SKAO Director-General Professor Philip Diamond said the image illustrates the dawn of the Observatory as a science facility as it opens its eyes to the universe.

“This first image is a critical step for the Observatory, and for the astronomy community; we are demonstrating that the system as a whole is working,” Diamond said. “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.”

Pictured: The first image from an early working version of the SKA-Low telescope. The dots in the image look like stars but are in fact some of the brightest galaxies in the universe, seen in radio light. These galaxies are billions of light years away and each contains a supermassive black hole. Gas orbiting around black holes is very hot and moves quickly, emitting energy in X-rays and radio waves. SKA-Low can detect these radio waves that have travelled billions of light years across the universe to reach Earth. At the centre of the image is one of only a handful of galaxies known to expel jets of matter that are visible in both optical and radio light. Image courtesy SKAO under CC BY 3.0