The sq. kilometer array has formally acquired the inexperienced mild to start out building
There are a number of radio telescopes in Australia and South Africa, which will soon be supplemented by a number of newly built systems for the Square Kilometer Array (SKA). Once in place, the SKA will have a collection area of one million square feet (nearly 2 million square feet). It will also be 50 times more sensitive than any radio telescope currently in use and capable of taking surveys ten thousand times faster.
During a historic meeting on June 29, 2021, the member states of the SKAO Council voted to start construction. By the late 2020s, when the first light is expected, the array will consist of thousands of dishes and up to a million low frequency antennas. These will allow him to perform all kinds of scientific operations, from scanning the earliest periods in the universe to searching for extraterrestrial intelligence (SETI).
At its core, the SKA is based on a process known as interferometry, in which light from cosmic sources is collected by several telescopes and then combined into high-resolution images. For radio telescopes, this technique has the additional advantage that it enables observations in which only a subset of the entire array is available. With such a large collection area, the SKA will enable all kinds of revolutionary science.
A big effort
The SKA consists of four “predecessor facilities” which include the MeerKAT and the Hydrogen Epoch of Reionization Array (HERA) in South Africa and the Australian SKA Pathfinder (ASKAP) and the Murchison Widefield Array (MWA) in Australia. There are also the Pathfinder facilities outside of these two countries, consisting of the Allen Telescope Array in Northern California and the Low-Frequency Array (LOFAR) in the Netherlands.
These facilities are divided into two networks called SKA-Low and SKA-Mid, which describe the radio frequency range they cover. The decision to approve the construction follows two important development milestones for the SKAO. First, two key documents were published last year, the construction proposal for the observatory and the construction and implementation plan for the observatory, as well as a summary of both.
The documents are the result of over seven years of design and engineering by more than 500 experts from 20 countries, whose purpose it was to test the technologies required to build and operate the largest radio telescope assembly ever built. Second, at the beginning of the year, the SKAO was founded as an intergovernmental organization. As SKAO General Director Prof. Philip Diamond recently said in a SKAO press release:
“I’m excited. This moment lasted 30 years. Today, humanity is taking another giant step by pledging to build the largest scientific facility of its kind on the planet; not just one, but the two largest and most complex radio telescope networks developed to unravel some of the most fascinating secrets of our universe. “
“I would like to thank everyone who has helped make this possible over the past few decades, from the very beginning of the project until today, and especially all the teams who have worked so hard over the past few years and put a pandemic in difficult circumstances, Meeting deadlines and making this milestone possible. I would also like to thank our Member States for their vision and the trust they have placed in us by investing in large-scale, long-term research infrastructure at a time when public finances are under severe pressure. “
This organization now comprises eleven international consortia representing more than 100 research laboratories, universities and companies from all sixteen Member States who were responsible for developing the necessary hardware, software and infrastructure. These include Australia, Canada, China, France, Germany, India, Japan, Italy, the Netherlands, Portugal, South Africa, South Korea, Spain, Sweden, Switzerland and the United Kingdom.
The construction period is to last until 2028, with the first scientific operation to follow in the early 2030s. The cost of the entire project, including the construction of the two telescopes, associated operations, and business-promoting functions, is estimated at € 2 billion ($ 2.38 billion) over nine years (2021-2030). The first noteworthy on-site activities are expected to take place early next year, but large-scale procurement will begin immediately.
In the next few months, the SKAO will award around 70 contracts to all of its member states, who will then offer them to tender on site. SKAO expects that once the two arrays begin collecting light, they will remain scientifically productive for 50 years or more. Dr. Catherine Cesarsky, Chair of the SKAO Council, thanked everyone who helped bring SKA to this crucial point in its development:
“I would like to thank the members of the SKAO Council and the governments they represent. Giving the green light to the construction of the SKA telescopes shows their confidence in the professional work of SKAO to come here, with a solid, ready-to-implement plan and into the bright future of this groundbreaking research … The commitment of the Member States today is strong Signal for others to get on board and take advantage of the benefits of participating in this unique research facility. “
Common advantages Benefit
In addition to providing exciting and revolutionary science, the organization claims that the SKA will bring tangible social and economic benefits to the countries concerned – such as innovation, technological spin-offs, new high-tech jobs, increased industrial capacity, and others. In addition to the member states, this also includes the African partner countries – including Ghana, Kenya, Zambia, Mozambique, Namibia, Botswana and Madagascar.
Then there are the many indigenous peoples in South Africa and Australia on whose land the telescopes are built. To encourage respectful dialogue and engagement, the San Council of South Africa (SCSA) and the South African Radio Astronomy Observatory (SARAO) have signed a letter of intent. Since then, the basic support of the project by the Wajarri Yamaji (on whose land the SKA Low Telescope is to be built) has been announced.
“SKAO will be a good neighbor and will work with local stakeholders, especially indigenous communities, to ensure that they benefit from the SKA project alongside other stakeholders at national and international levels,” added Prof. Diamond. “We definitely intend to do our part to support local communities and boost the local economy.”
In view of the scientific possibilities, the SKA will conduct a variety of observations that will provide valuable scientific knowledge. In particular, the SKA will conduct some of the toughest tests of general relativity to date, in which astronomers observe how the path of electromagnetic radiation changes due to the influence of gravitational fields and the curvature of space-time.
The SKA’s sensitivity will allow it to observe the spectral line of radiation created by a change in the energy state of neutral hydrogen atoms – also known as. the 21 cm hydrogen pipe. This will enable the SKA to break the veil of the cosmic “Dark Age” when the first galaxies formed. It will also allow astronomers to see how the large-scale structure of the universe has evolved since then, and provide insight into the role of dark matter and dark energy.
The SKA will also enable some of the strictest surveys to date in the search for extraterrestrial intelligence (SETI). Traditionally, radio astronomy has been the preferred means of looking for signs of technological activity (i.e., technosignatures), and the SKA’s multiple telescopes will be able to monitor target star systems at different radio wave frequencies over extended periods of time.
In recent years the enthusiasm for the SKA and its cosmic mysteries has not only grown in science. The SKA is seen by the general public as a next generation institution that will grapple with many of the lingering secrets of the cosmos. And like the James Webb Space Telescope (JWST), the Extremely Large Telescope (ELT), and many others, we only have to wait a few more years for the scientific returns to arrive.
Further reading: SKOA