First SKA-Mid Dish Installed in South Africa

Sydney, Australia (SPX) Jul 10, 2024 - A team from the SKAO, South African Radio Astronomy Observatory (SARAO), and China's CETC54 successfully mounted the 15-meter-wide main reflector onto the SKA-Mid telescope pedestal in South Africa. This milestone is part of a larger effort involving a consortium from ten countries, led by CETC54, which is also manufacturing the dishes.

Over the past year, construction has accelerated at SKAO's telescope sites, including the deployment of SKA-Low telescope antennas in Western Australia this past March.

"The progress this year across the Observatory has been amazing, and seeing the first SKA-Mid dish being erected is a significant moment as we head towards the first stage of telescope delivery," said SKAO Acting Director of Programmes Luca Stringhetti.

"There have been challenges, as we anticipated there would be, but it is thanks to the coordinated effort and support of our partners across the globe, combined with significant logistical work by teams at the telescope sites and our HQ, that we have been able to deploy the first dish structure and four stations on the ground in both of our telescope host countries."

SKA-Mid will consist of 197 dishes stretching across 150 km in Northern Cape province, covering frequencies from 350 MHz to 15.4 GHz, with potential future expansion up to 24 GHz. These dishes will study a wide range of astronomical phenomena, including fast radio bursts, gas distribution in galaxies, and complex organic molecules that could be the precursors to life.

"CETC54 is excited and deeply proud to be part of installing the first SKA-Mid dish in South Africa, which is set to operate for over 50 years. Since its conception, the SKA project has embodied the collective aspirations and efforts of many institutions in the pursuit of cosmic exploration," said Wang Dawei, SKA-Mid Dish Project Manager at CETC54.

"The precise installation of the main reflector is just the first step, and we will continue to implement high-precision measurement adjustments and accurate calibration on the antennas, in order to deliver the dishes to the SKAO's exacting quality standards."

The SKA telescopes are being developed in phases to provide optimal instruments at each stage, allowing for testing and reviews before full-scale production. The newly completed dish is part of the initial phase known as Array Assembly 0.5 (AA0.5).

"As a team we are now totally focused on the next stage of activities because we have already got two more dish structures on site, ready for assembly," said SKA-Mid Site Construction Director Tracy Cheetham. "This is a complex environment, with many variables, but we are in a strong position to proceed with the next steps towards AA0.5."

Components for SKA-Mid are being produced in several SKAO partner countries, including Italy, Spain, Sweden, the UK, and South Africa. The Stellenbosch-based EMSS Antennas, specialists in cryogenically cooled receivers, was awarded the contract to build SKA-Mid's band 2 receiver.

The next step for the first SKA-Mid dish is installing the feed indexer, which positions receivers for different observations.

"There's a lot of work ahead of us, but for everyone involved, this is a special moment that represents years of toil by people all over the world, so I want to thank them for their dedication in getting us here. Special thanks must go to our partners at SARAO and CETC54 for their professionalism and commitment - this collaboration is really bearing fruit," said SKA-Mid Senior Project Manager Ben Lewis.

"The first of anything is always the most challenging, and we have learnt a huge amount from a logistical and technical perspective from this first dish. That will inform our planning going forward as we prepare to deliver a four-dish array early next year, before ramping up to 'full speed' construction later in 2025."

In Australia, SKA-Low telescope construction is also progressing swiftly. Four of the planned 512 stations have been completed, with over 1,000 antennas installed at the CSIRO Murchison Radio-astronomy Observatory on Wajarri Yamaji Country. Once finished, the SKA-Low telescope will include 131,072 antennas and cover frequencies from 50 MHz to 350 MHz, complementing SKA-Mid.