SKAO Telescope in South Africa Achieves Key Commissioning Milestone
The Square Kilometre Array Observatory’s (SKAO) expanding telescope array in South Africa, SKA-Mid, has reached a key commissioning milestone by recording “first fringes.” This milestone, achieved using two of its 15-metre dishes, represents the first successful combination of signals from two or more antennas in the array. This milestone demonstrates that the system is operating as an interferometer for the first time, confirming that the hardware and software systems are functioning together as intended and marking a key step toward full scientific operation.
The initial observation targeted a well-studied radio galaxy approximately 2.6 billion light-years away, enabling the project team to validate that signals from the two dishes could be combined successfully. The achievement demonstrates that the dishes can track the sky in a coordinated manner and that the receivers are maintained at the required operating temperature of -250°C. It also confirms that the timing and correlator systems accurately synchronise signals to within a billionth of a second and that the correlator is correctly processing and aligning the data.
“This gives us confidence as we begin the telescope’s commissioning,” said Dr Betsey Adams, SKA-Mid Commissioning Scientist.
SKA-Mid Progress in South Africa
Currently, seven SKA-Mid dish structures have been assembled on site in the Northern Cape, with a further 12 en route from manufacturer CETC54 in China. When completed, the array will comprise 197 dishes, incorporating the existing MeerKAT radio telescope operated by the South African Radio Astronomy Observatory (SARAO). Furthermore, the hardware and software for the SKA telescopes are being developed across the Observatory’s partner states, reflecting a collaborative effort between local teams, international partners, and the South African Radio Astronomy Observatory (SARAO).
The successful achievement of first fringes marks a significant validation of these combined efforts and provides a strong foundation for the next stages of commissioning. Building on the experience gained during the lead-up to this milestone, the SKA-Mid project is now positioned to achieve the first images from a four-dish array in the coming months. From there, the telescope will continue to expand gradually, increasing in size and capability as additional dishes and supporting infrastructure are brought online, moving steadily toward its full scientific potential.