Minimize SKA (Square Kilometer Array)

SKA (Square Kilometer Array) Radio Telescopes

SKA Location    Overall Status    Australia Antenna Array  ASKAP development and mission status
Africa Radio Telescope Array    MeerKAT development and mission status   References    

The SKA project is an international effort to build the world's largest radio telescope, with eventually over a square kilometer (one million square meters) of collecting area. The scale of the SKA represents a huge leap forward in both engineering and research & development towards building and delivering a unique instrument, with the detailed design and preparation now well under way. As one of the largest scientific endeavors in history, the SKA will bring together a wealth of the world's finest scientists, engineers and policy makers to bring the project to fruition. 1)

Background: The history of the SKA begin in September 1993 the International Union of Radio Science (URSI) established the Large Telescope Working Group to begin a worldwide effort to develop the scientific goals and technical specifications for a next generation radio observatory. 2)

Subsequent meetings of the working group provided a forum for discussing the technical research required and for mobilizing a broad scientific community to cooperate in achieving this common goal. In 1997, eight institutions from six countries (Australia, Canada, China, India, the Netherlands, and the USA) signed a Memorandum of Agreement to cooperate in a technology study program leading to a future very large radio telescope.

On August 10, 2000, at the International Astronomical Union meeting in Manchester, UK, a Memorandum of Understanding to establish the ISSC (International Square Kilometer Array Steering Committee) was signed by representatives of eleven countries (Australia, Canada, China, Germany, India, Italy, the Netherlands, Poland, Sweden, the United Kingdom, and the United States).

This was superseded by a Memorandum of Agreement to Collaborate in the Development of the Square Kilometer Array which came into force on 1 January 2005 and which has been extended until 31 December 2007. This made provision for the expansion of the Steering Committee to 21 members (7 each for Europe, USA, and the Rest of the World) and the establishment of the International SKA Project Office.

In 2007, owing to a proposed expansion of the ISPO (International SKA Project Office), the ISSC called for proposals to host the Project Office. Three proposals were received, and following extensive discussion, the ISSC selected the University of Manchester as the host organization for the Project Office. A Memorandum of Agreement between the ISSC and the University of Manchester was signed in October 2007. The Project Office moved to the new Alan Turing building in Manchester, also home to the Jodrell Bank Center for Astrophysics, on 1 January 2008.

A new International Collaboration Agreement for the SKA Program was drawn up in 2007, which became effective on 1 January 2008. It was signed by the European, US, and Canadian SKA Consortia, the Australian SKA Coordination Committee, the National Research Foundation in South Africa, the National Astronomical Observatories in China, and the National Center for Radio Astrophysics in India. This agreement established the SKA Science and Engineering Committee (SSEC) as a replacement to the ISSC. The SSEC acts as the primary forum for interactions and decisions on scientific and technical matters for the SKA among the signatories to the International Collaboration Agreement.

A further agreement was drawn up in 2007, a Memorandum of Agreement to establish the SKA Program Development Office (SPDO). This provided a framework to internationalize the technology development and design effort of the SKA. This agreement, which became effective on 1 January 2008, was signed by the CSIRO Australia Telescope National Facility, University of Calgary, Cornell University, the Joint Institute for VLBI in Europe, and the National Research Foundation in South Africa. It agreed that the SPDO would be funded by signatories of this agreement, with payments being made into the SPDO Common Fund and used to finance the SPDO's operational activities.

The project is now led by the SKA Organization, a not-for-profit company. The organization was established in December 2011 to formalize relationships between the international partners and centralize the leadership of the project.

The Office of the SKA Organization is growing rapidly and in November 2012 the office, previously based at the University of Manchester in the center of the city, relocated to a new building at the world famous Jodrell Bank Observatory in Cheshire, UK. The SKAO Headquarters is the central control hub for a global team who over the next decade is building the SKA – The largest radio telescope ever seen on Earth.

Participating Countries: Organizations from eleven countries are currently members of the SKA Organisation – Australia, Canada, China, India, Italy, New Zealand, South Africa, Spain, Sweden, the Netherlands and the United Kingdom. Further countries have expressed their interest in joining the SKA Organisation which will continue to expand over the coming years. 3)


Figure 1: While 11 member countries are the core of the SKA, around 100 organisations across about 20 countries (including France, Germany, Japan, Portugal) have been participating in the design and development of the SKA and are now engaged in the detailed design of the telescope (image crdit: SKA)

Here is a list of links to the key participating nations:

- Australia: Department of Industry and Science

- Canada: National Research Council

- China: Ministry of Science and Technology of the People's Republic of China

- India: National Centre for Radio Astrophysics

- Italy: National Institute for Astrophysics

- New Zealand: Ministry of Economic Development

- South Africa: National Research Foundation

- Spain: Ministry of Science, Innovation & Universities

- Sweden: Onsala Space Observatory

- The Netherlands: Netherlands Organisation for Scientific Research

- United Kingdom: Science and Technology Facilities Council

• During 2013, the SKA Organization sent out requests to research organizations and commercial partners to participate in the analysis and design of the components of the SKA's 3-year final detailed design phase. This request for proposals included a reference conceptual design of the telescope, a work breakdown structure, a statement of the work required and additional reference documents. 4)

- As with other projects of this magnitude, such as the development of the Large Hadron Collider or space programs, the SKA is broken down into various elements, known as work packages that will form the final SKA telescope. Each work package element is managed by an international consortium comprising several world leading experts in their respective fields.

- The strategic aim of the SKA Organisation is that the work undertaken within each of the consortia is focused on these specific elements of the SKA project and that their work will cover the entire final phase of the pre-construction period, with critical design reviews along the way.

- The SKA Organisation will play a key role in the management of these teams around the world, ensuring that all of the elements integrate to form this unique telescope over the coming years. Each consortium has provided detailed management and verification plans, schedules, milestones and budgets for the various elements they will be working on.

- The consortia responsible for each work package are listed as follows. Click on each to get more detailed information on each work package and the team responsible for its delivery.

a) Assembly, Integration and Verification (AIV)

b) Central Signal Processor (CSP)

c) Dish (DSH)

e) Infrastructure Australia and Africa (INFRA AU/INFRA SA)

f) Low-Frequency Aperture Array (LFAA)

g) Mid-Frequency Aperture Array (MFAA)

h) Signal and Data Transport (SaDT)

i) Science Data Processor (SDP)

j) Telescope Manager (TM)

k) Wideband Single Pixel Feeds (WBSPF)

Collaboration between the various teams will be a key part of their involvement, as there will be a huge requirement to ensure that the various elements interface seamlessly together, much like a jigsaw, but one that will be refined and iterate to a better solution as time progresses.

Technical descriptions for the Work Packages at a global level

Summaries of Technical Descriptions for each of the Work Packages are as follows: (PDF links)

- Assembly, Integration and Verification (AIV)

- Central Signal Processor (CSP)

- Dish (DSH)

- Infrastructure South Africa (INFRA SA)

- Low-Frequency Aperture Array (LFAA)

- Mid-Frequency Aperture Array (MFAA)

- Signal and Data Transport (SaDT)

- Science Data Processor (SDP)

- Telescope Manager (TM)

- Wideband Single Pixel Feeds (WBSPF)

• January 23, 2017: SKA-AAMID (Aperture Array MID Frequency) telescope. 5)


The Location of the SKA

In 2012 the members of the SKA Organization agreed on a dual site location for the Square Kilometer Array telescope as well as a third site for the SKA HQ. 6)

The two sites which will host the core of the SKA Telescope are Australia and South Africa, whilst the SKA Organization Headquarters is in the UK.

This decision to collocate the telescopes in two sites came after careful consideration of all of the science goals, industry goals and suitability in terms of location, sustainability, local considerations and factors relating to economics and the site infrastructure.

The following are some of the criteria that were taken into account:

• Radio frequency interference from mobile phones, TVs, radios and other electrical devices.

• The characteristics of the ionosphere (the upper part of the Earth's atmosphere) and the troposphere (the lower part of the Earth's atmosphere).

• Physical characteristics of the site including climate and subsurface temperatures.

• Connectivity across the vast extent of the telescope itself as well as to communications networks for worldwide distribution of data produced by the SKA.

• Infrastructure costs, including power supply and distribution.

• Operations and maintenance costs.

• The long term sustainability of the site as a radio quiet zone.

In July 2013, the SKA Board passed the following resolution: ‘Following the recommendation of the Director-General of the SKA Organization, the SKA Board has instructed the SKA Office to proceed with the design phase for SKA Phase 1 (SKA1) assuming a capital expenditure cost ceiling for construction of €650 M. The evolution of the SKA Phase 1 project to fit within this cost ceiling will be guided both during the design phase and construction by scientific and engineering assessments of the baseline design undertaken by the SKA Office in collaboration with the community and SKA's advisory bodies including the Science and Engineering Advisory Committee (SEAC). This decision is consistent with the primary objective of building an exciting, next-generation telescope capable of transformational science.'

SKA1 boundary conditions

• Site decision May 2012: SKA Observatory with two sites

- SKA1-low – Australia

- SKA1-survey – Australia

- SKA1-mid – South Africa

• Incorporate precursors on the sites to re-use as much existing infrastructure as possible

• SKA Board has set a cost-cap of €650 M for SKA1 construction

SKA1 design timeline

• 2013 start of preliminary design (4 November)

• 2014 complete preliminary design; re-baseline the Baseline Design

• 2016 complete detailed design

• 2017 initiate procurement/ pre-production runs

• 2018 start construction

SKA1-MID headline science

• HI-line (21 cm hydrogen line) from local Universe, to moderate redshifts

• Radio pulsars

• High sensitivity continuum

- Polarisation: magnetized plasmas, Galactic & Extragalactic

- potentially proto-planetary disks, if high frequency receivers enabled

• Other spectral lines (e.g. OH-lines)

• Some classes of radio transients

SKA1-MID baseline design

• Mixed Dish array

- 190 x 15 m SKA1 dishes

- 64 x 13.5 m diameter dishes from the MeerKAT array

- Equipped with receivers from 0.350 to 3.0 GHz for SKA1 (dishes capable of 5 receiver packages up to 20 GHz)

• Configuation

- Compact core with a diameter of ~1 km, built on the MeerKAT array center

- Further 2-D array of randomly placed dishes out to ~3 km radius, thinning at the edges

- Three spiral arms, a subset of the 5 equally spaced arms reserved for SKA2, extending to ~100 km from the center

- Array to be expanded to a much larger SKA2 array (by "density matching")

• Sensitivity

- SKA1 sensitivity: ~6.9 m2/K

- SEFD (System Equivalent Flux Density) : ~1.7 Jy

Table 1: SKA1 baseline design: boundary conditions, design timeline, MID baseline sciene, MID baseline design 7)


Figure 2: SKA1 construction start 2018 (image credit: SKA Office)


Figure 3: SKA2 construction start 2022 (image credit: SKA Office)


Figure 4: SKA overall timeline (image credit: SKA Office)


SKA overall status

• June 2, 2020: South Africa, the future home of the SKA's mid-frequency telescope, has ratified the Convention Establishing the SKA Observatory after the South African Parliament approved the Convention and Dr Naledi Pandor, Minister of the Department of International Relations and Cooperation, signed the Instrument of Ratification. 8)

- It is the third country after the Netherlands and Italy to complete its national process supporting the establishment of the SKA Observatory; the intergovernmental organisation responsible for building and operating the SKA telescopes, and the first of the SKA's three host countries to do so.


Figure 5: Close up of the certified copy of the SKA Observatory Convention kept in the Council Chamber of SKA Global Headquarters (image credit: SKA Organisation)

- South Africa was among the seven countries that signed the Convention in Rome on 12 March 2019, alongside Australia, China, Italy, the Netherlands, Portugal and the United Kingdom. The Convention will enter into force once five countries, including the three hosts Australia, South Africa and the UK, ratify the text.

- "This is a significant moment not only because South Africa is the first of our hosts to ratify the Convention, but with multiple countries having done so, we are now closer to the SKA Observatory formally existing," said SKA Director-General Prof. Philip Diamond.

- The South African Radio Astronomy Observatory (SARAO) has been leading the country's participation in the SKA on behalf of the Department of Science and Innovation.

- South Africa is already home to two precursor telescopes: the 64-dish MeerKAT array which will ultimately form part of the SKA's mid-frequency telescope, and the Hydrogen Epoch of Reionisation Array (HERA), which is under construction. As well as conducting world-class research, MeerKAT is also providing vital input for SKA design work and science planning.

- "Ratification is a critical milestone for the SKA project. I would like to thank both Houses of Parliament as well as the Department of Science and Innovation for supporting our country's participation in this iconic global science infrastructure project," said Rob Adam, Managing Director of SARAO.

- South Africa's radio astronomy and related engineering expertise has evolved rapidly in the past two decades, and the contribution of South African institutes and industry in the detailed design work of the SKA has been invaluable. Recently, stunning early images from MeerKAT – currently the world's most powerful radio telescope in its category – have cemented the country's position in the premier league of radio astronomy. Scientists at South African institutions are also active in 10 of the SKA's Science Working Groups and Focus Groups.

- "South Africa's ratification of the Convention confirms South Africa's strong commitment to the global SKA partnership. We are determined to ensure the success of what will be the first ever large global research infrastructure hosted in Africa," said Dr Blade Nzimande, South Africa's Minister of Higher Education, Science and Innovation. "South Africa's participation in the SKA project has significantly strengthened South Africa's data science capabilities, precious resource in the fight against COVID-19. More than ever our world needs international cooperation and solidarity in science such as enabled by projects such as the SKA."

- "Even with the terrible toll of this novel coronavirus around the world, countries have shown remarkable commitment to the SKA and continue to push forward. It is testimony to the strength of our global collaboration and the impact the project will have," added Prof. Diamond. "Momentum is strong, and we expect Australia, China, Portugal and the UK to ratify in the coming months, with other countries joining the Observatory in due course. Once the SKA Observatory is up and running, construction of the largest science facility on the planet will begin in earnest."

• May 4, 2020: Construction of the giant Square Kilometer Array (SKA) is likely to be delayed by several months, with COVID-19 lockdown measures making some tests of prototype equipment impossible, and parliaments slower to ratify the intergovernmental convention governing the building and operation of the radio telescope. 9)

- Nine years after it was agreed SKA would be split between sites in South Africa and Australia, building the telescope was due to start in January 2021. But last week Philip Diamond, director general of the SKA Organisation, said COVID-19 enforced delays mean the project is now aiming for, "commencement of SKA1 construction activities as early in 2021 as possible."

- Diamond hopes the delay will be minimal. "If it's two or three months, we'll count that as a success," he said. SKA's headquarters at Manchester University's Jodrell Bank Observatory where Diamond is based, have now been shut down for more than six weeks. In an update last week, he said, "It is my expectation that the shutdown will continue for some weeks yet."

- A few months looks like marginal in terms of the time frame for the project, with SKA not due to be fully operational until 2030. Once complete, the telescope will have the capacity to look back in time to the first billion years of the universe and the formation of the first stars and galaxies.

- That will be achieved by combining data from a collection of large antennas spread across remote areas of South Africa and Australia. The €1.8 billion international project also involves Spain, Italy, Germany, Switzerland, China, Canada and India, amongst other countries.

• April 28, 2020: I hope that all of you and your families are safe and healthy in this crisis that has gripped the world. It is heartening to see the way that our fellow citizens across the globe have risen to the challenges imposed by the pandemic, especially the way in which the world's health professionals have stepped up, often at risk to themselves. I salute them all. 10)

- It is now nearly six weeks since the SKA HQ building was shut down as a response to the coronavirus pandemic. It is my expectation that the shutdown will continue for some weeks yet. Within the senior leadership of the SKA Organisation we are planning the eventual return to the office but will be following the advice of the UK government in making any decisions. Any and all decisions on a physical return will be taken ensuring the health and well-being of our staff and their families above all else.

- Thanks to some careful planning, an efficient IT team, robust technology and a digitally-savvy workforce, SKA staff have managed to rapidly settle into the new working environments and establish new working practices. As I am sure is the case all over the world, this has not come without issues, as our colleagues cope with families at home and isolation for those who live alone. We have had, for many years, a flexible work culture and this has come to the fore during the past few weeks. Our Human Resources team have been in contact with all lone workers to ensure they are managing, and we have set up systems whereby they can meet and socialise with their colleagues via videoconferencing.

- Some of our staff returned to their home countries prior to the shutdown to be with their families; they continue to work remotely, and we will work with them to plan their eventual return to SKA HQ.

- In the weeks since the lockdown commenced, we have had 7 new starters at SKAO. All have been inducted remotely and are fully incorporated in all SKA activities within their new teams. We look forward to the time when we can meet them in person and welcome them with a NAMASTE, the replacement for a handshake.


Figure 6: Public statement on the status of the SKA project (Philip Diamond, SKA Director-General)

- On the project side, we continue to progress well. We have had several positive milestones over the last four weeks and have been maintaining the strong momentum that was evident across all aspects of the project before the pandemic hit. Those key milestones are:

1) The System Critical Design Review, the meeting for which took place in December last year, was completed in early April, with all actions closed off except those few which, with the full agreement of the panel, require continued technical investigation of prototype systems. This has been a huge effort by all involved, both within the office and across our global partnership.

2) The external review of the SKA Operations Plan took place by video on 23-25 March; the panel's very positive report was received shortly thereafter. We have accepted and are implementing all of their recommendations. There are no major issues, but some wise advice was provided in areas of budgetary contingency, lean staff levels in one or two areas, the complexity of managing an operation across three continents and the relationships with the proposed SKA Regional Centres.

3) The Cost Audit of the SKA1 construction plans was completed a week or so ago. This was conducted by Arup, a global engineering company. Again, the report was very positive with a range of extremely useful recommendations. These mainly focused on issues of detailed process and did not turn up any major concerns with regard to the cost estimates or the contingency estimation process.

4) On Monday 20th April, EPFL (the École Polytechnique Fédérale de Lausanne) joined the SKA Organisation, representing Switzerland; they are SKA's 14th Our Swiss colleagues have, over the past 4 years, become increasingly engaged in SKA activities and we welcome them into the project.

5) On 21st April, we were pleased to hear that the legislation to progress the UK's ratification of the SKA Observatory Convention was laid before the UK Parliament; this will now progress through the UK processes over the coming weeks.

- In addition to supporting these milestones, the SKAO staff are focusing on several areas, namely: developing the draft Construction Proposal, which will be ready for internal review shortly; further development of the procurement strategy; updating the Operations Plan and developing the broader 10-year plan for the Establishment and Delivery of the Observatory; engaging in the newly-established SRC working groups; drafting the business plan for 2021; preparing for the review of business-enabling functions; working on several different aspects related to the transition from the SKA Organisation to the SKA Observatory; working on the second Data Challenge; drafting the next version of Contact, developing the thinking around the future SKA Observatory brand and much more.

- I also would like to say that I am impressed at how the SKA community around the world has stepped up to assist during the COVID-19 crisis; from our colleagues in South Africa taking the lead on provision of ventilators at their government's request; to work on contact tracing apps in Australia; supporting super-computing work on the virus and vaccines in many partners; and the provision of online educational resources by colleagues in India, Italy, the UK and elsewhere. I'm sure there are many more examples. These actions demonstrate the skillsets and experience such teams can bring to the table to assist at these critical times.

- As we look to the future, we are, with the full support of the Board and the SKA Observatory Council Preparatory Task Force (CPTF), the body preparing for the new governance structure under the treaty, planning for the establishment of the Observatory later this year and for the commencement of SKA1 construction activities as early in 2021 as possible. As is natural, we are undertaking planning for a range of possible scenarios with the intent of being able to respond appropriately and rapidly as the world emerges from this crisis. None of us can predict what the coming months will bring but, as one of the world's major scientific endeavours, we hope to push forwards bringing employment, innovation and scientific exploration to benefit our partner countries.

• April 20, 2020: The Swiss science and technology university École Polytechnique Fédérale de Lausanne (EPFL) has become the 14th member of the SKA Organisation (SKAO) following a unanimous decision by the SKA Board of Directors. 11)

- EPFL will be the lead institution coordinating involvement in the SKA on behalf of the Swiss academic community. Note: The Swiss Academic Community includes Universities of Geneva, Zurich, Bern, ETHZ, CSCS, FHNW, HES-SO, and Verkehrshaus Lucern.

- "I am delighted to welcome EPFL to the SKA Organisation as our newest member," said Chair of the SKA Board of Directors Dr Catherine Cesarsky. "This renowned research institution and its partners have brought valuable expertise to the SKA, and we look forward to working ever more closely with our Swiss colleagues as we enter this exciting phase of the project, completing the very last steps before construction."

- At a national level, Switzerland has held observer status within the Organisation since 2016, with many Swiss research institutions and many industry partners contributing to various aspects of the SKA. The country has a history of world-class research and development in science and astronomy, including leading the recent CHEOPS mission to study exoplanets, developing world-leading instrumentation for the ESO telescopes in Chile, and being one of the hosts of the major international particle physics infrastructure CERN.

- Scientists at Swiss institutions are active in eight of the SKA's science working groups, including those focusing on galaxy evolution, cosmology and cosmic magnetism.

- "This new high-performance radio telescope will open a new view of the whole Universe," said Prof. Jean-Paul Kneib of EPFL, who is leading the consortium of Swiss scientists interested in the SKA. "SKA will allow us to address some key questions on our Universe, such as the nature of the dark matter and the dark energy, or explore the Cosmic Dawn, the period of time when the first stars and first galaxies formed."

- The white paper Swiss Interests and Contribution to the SKA, published in February 2020, outlines the extensive Swiss involvement in SKA-related science and technology, and highlights national interest in contributing research and development in the fields of distributed radio frequency systems, high performance computing, machine learning and artificial intelligence. It also notes Swiss industry expertise in data processing, system control and supervision, antennas and radio receivers and precise time management through the use of maser atomic clocks.

- Annual Swiss SKA Days are now in their fifth year, bringing together national and international representatives of academia, industry and government, showcasing the breadth of opportunities for Swiss institutions and companies to be involved in the SKA. The location rotates each year to reflect the various contributions of different Swiss institutions. The next Swiss SKA day is due to be held at the University of Zürich later this year.

- EPFL is now a member of the SKAO, which has been responsible for overseeing the telescope design phase, until the process of transitioning into the SKA Observatory is completed. The Observatory is due to come into being in 2020. Switzerland's Federal Council recently triggered the first political debate in parliament regarding the possible participation of Switzerland as a member state in the future.

- "As the dream of building SKA is about to become a reality, the State Secretariat for Education, Research and Innovation (SERI), welcomes and supports the EPFL decision to join the SKA Organisation as a special member. The accession of the EPFL will benefit to the Swiss scientific community as a whole and will open business perspectives to Swiss companies," said Xavier Reymond, Deputy Director General for International Research Organisations at SERI, who is in charge of the relationship between Switzerland and SKAO.

- "Switzerland is the proud Seat of CERN and a dedicated member of the European Southern Observatory and of the European Space Agency. Therefore, we all look forward to assessing the opportunity to complement these intergovernmental endeavors with the upcoming SKA Observatory, which shares the same dedication to better understanding the Universe."

- SKA Director-General Prof. Philip Diamond also welcomed EPFL to the SKAO, noting the importance of the country's involvement so far. "Swiss institutions have been a vital part of the SKA's design phase and bring with them a well-deserved reputation for excellence in science and astronomy, as well as being involved with some of today's most exciting projects," he said. "As we move ever closer to SKA construction, EPFL's membership serves to highlight the broad range of expertise that the SKA can count upon in this next phase."


Figure 7: The main EPFL campus in Lausanne sits on the shores of Lake Geneva (photo credit: Mediacom EPFL; CC BY-SA 4.0)

• April 9, 2020: The South African Department of Trade, Industry and Competition has tasked SARAO (South African Radio Astronomy Observatory) with managing the national effort required for the local design, development, production and procurement of respiratory ventilators to support the government's response to combat the COVID-19 (coronavirus) pandemic. 12)

- SARAO has been mandated to manage the National Ventilator Project based on the experience it gained in the development of complex systems for the MeerKAT radio telescope, an SKA precursor facility.

- "We are happy and proud to lend our expertise developed in the context of MeerKAT and the SKA to fight this global pandemic and protect our country" said Dr. Rob Adam, Managing Director of SARAO.

- The South African government has called on companies and experts, particularly engineers and scientists, to come with innovative solutions to help combat the pandemic. In an effort to meet the anticipated demand for critical medical equipment such as ventilators, the Department of Trade, Industry and Competition is inviting companies and experts to express their interest in the design, development, production and procurement of ventilators in South Africa.

• February 5, 2020: Italy has become the second country to ratify the SKAO (SKA Observatory) Convention, the treaty which establishes the intergovernmental organization that will build and operate the SKA telescopes. 13)

- On Thursday 30th January, the Italian Senate passed the law that authorizes the President to ratify the Convention. In the text, Italy announced a financial commitment of 120 million euros over 10 years for the project.

- Italy led the multilateral negotiations on the text of the Convention, which was signed in Rome last year by seven countries: Australia, China, Italy, the Netherlands, Portugal, South Africa and the United Kingdom. The Convention will enter into force once five signatories, including the three hosts Australia, South Africa and the UK, have ratified the text. Italy becomes the second country to do so after The Netherlands last August.

- Italy's National Institute of Astrophysics (INAF) has been coordinating Italian participation in the SKA.

- "INAF has been part of the project from its foundation with an indisputable contribution in terms of science, technological development and industrial participation," says INAF President Nichi D'Amico. "Now the internal R&D activities within INAF are of fundamental importance, necessary to capitalize the return for the country of the government's contribution to the Organization in terms of science, industry and development of innovative technologies."

- Italian institutions and industry have been instrumental in the design phase of the SKA, particularly in prototyping work for the SKA's low-frequency antennas. INAF is involved in a number of world-class radio astronomy facilities, including operating the 64m Sardinia Radio Telescope (SRT) and hosting one of the international LOFAR telescope stations. Italian researchers are involved in all 13 of the SKA's Science Working Groups.

- "We're seeing great momentum towards construction with the recent completion of our system engineering review and now the Italian ratification. It's a great step towards establishing the SKA Observatory in the coming months" said SKA Director-General Prof. Philip Diamond.

December 19, 2019: An independent panel of external reviewers from major astronomy projects has given the SKA's overall design, costing & planning the nod, clearing the way for the preparation of the SKA construction proposal. 14)

- After six years of work involving hundreds of engineers and scientists in 20 countries and close to 300 institutions around the world, the SKA's overall system design – how all parts of the SKA work and interact with one another -, costing & planning has been endorsed by a panel of leading experts from ESO, NRAO, LSST, Gemini, NSF, Berkeley & Caltech universities, representing some of the biggest astronomical facilities in the world.

- "If you look at what has been achieved in the last few years it is really quite remarkable," said Dr. Adrian Russell, Chair of the Review Panel from ESO "This year in particular there has been a huge push with [....] the design really coming to maturity. Certainly looking from the outside it is very, very impressive."

- In November 2013, 12 international engineering consortia were created and tasked with designing the SKA. Nine of the consortia focused on the SKA's core elements, while three others were tasked with developing advanced instrumentation. In late 2018 and 2019 consortia started going through their Critical Design Reviews (CDRs), during which the proposed design for each of these elements had to meet the project's tough engineering requirements to be approved. The system review was the last major hurdle to be overcome before a construction proposal can be developed.

- "They have done a tremendous job of actually getting the consortia to the point where they are able to move forward with the actual construction," said Dr. Alison Peck, member of the Review Panel from Gemini Observatory.

- As part of the design work, international teams have been engaged in building and testing prototypes on the SKA sites in South Africa and Australia, in order to make sure the design can cope with the harsh environment and meet the stringent radio frequency interference requirements on site. That work is ongoing as teams refine the design of the antennas based on lessons learned in the field.

- ‘The team has really been outstanding and I speak not only of the team here at the HQ but also the broader team from our member institutions," said Dr. Joe McMullin, Program Director and Deputy Director-General of the SKA. "Having this milestone is really the foundation for everything in 2020. This is the year where we have to pull together the construction proposal itself."

- Teams will now engage in final preparations ahead of construction, addressing recommendations from the panel. as the new intergovernmental organization that will oversee the procurement, construction and operation of the SKA starts operating.

- "We've gotten our wish. We get to continue to move forward on the project and it is fantastically exciting to see this observatory beginning to come together," concluded Dr. McMullin.


Figure 8: SKA overview at CDR (Critical Design Review) — Exploring the universe with the world's largest radio telescope (video credit: SKA)


Figure 9: The SKA (Square Kilometer Array)

• On July 10, 2019, more than 200 guests had the pleasure to attend the ceremony for the official opening of the SKA Global Headquarters (HQs), located on the grounds of the historic Jodrell Bank Observatory and funded by the UK Government, Cheshire East Council and The University of Manchester. 15)

- Very nicely, the ceremony happened three days after the announcement of Jodrell Bank Observatory becoming one of the UNESCO World Heritage Site.

- The SKA Board members were invited to the event and had also the privilege to participate to a dedication ceremony, held in honor of the former SKA Board Chair (Prof. G. Bignami, 1944-2017), during which his widow (Dr. P. Caravero) named the SKA HQs auditorium "The Giovanni Fabrizio Bignami Council Chamber".

- After the early July announcement of New Zealand winding down its involvement in the SKA by the end of 2020, on July 11, 2019, the SKAO Board members had the pleasure to note that Spain's Ministry of Science, Innovation and Universities applied to upgrade from Associate Member to Special Member of SKA Organization, this status providing to Spain a greater access to the Company's decision-making processes.

- In addition to the usual updates on progresses related to governance, science, engineering, operation and procurement matters, a review of the SKA Brand was presented by W. Garnier (Director of Communications Outreach and Education). The Board discussions saw also a policy session, including a report on the outcomes of recent CPTF meetings by the Council Chair (P. Kelly); the SKA Organization Board was informed that the SKA Observatory Convention is likely to enter into force by mid-2020. In the same session, progresses to develop a partnership model for operations of SKA-Mid in South Africa and SKA-Low in Australia, as well plans for the transition between the SKA Organization and the SKA Observatory, were presented by S. Berry (Director of Strategy) and T. Devaney (Head of Business Development and Change), respectively.

- Quick progresses are on-going on all sides of the project. P. Diamond (SKAO DG) reported that, from the human resources point of view, 34 new roles have been advertised in the last year, attracting nearly one thousand candidates. The full implementation of a new Enterprise Resource Planning (ERP) has started and will need to take place in the next 18 months, before the establishment of the SKA Observatory. To be recalled that new jobs are regularly updated at the SKAO Recruitment Portal. Prof. Diamond also informed the Board that the SKAO is fully engaged in initiatives lead by the International Telecommunication Union (ITU) in order to ensure that new generations of constellations of low Earth orbit satellites will not compromise future SKA scientific results.

- R. Braun (SKA Science Director) gave an overview of recent activities of his team, with particular emphasis on the good participation of the community to the last SKA Science meeting and on the publication of the results of the First Science Data Challenge. This was the first of a series of challenges and was intended to test source finding and classification tools on nine different images, sampling three different frequencies - 0.56, 1.4 and 9.2 GHz - and three different exposure times - 8, 100 and 1000 hours.

- J. McMullin (Program Director) provided an update of the pre-construction missions, consisting in delivering a Construction Proposal and an Operations Plan. Key dates are related to the Adoption Design Review (ADR) meetings during July and very early August (which will establish the complete set of documents detailing requirements, design, interfaces and plans) and, above all, to the System Critical Design Review (CDR). The full publication of its documentation is expected by mid-October 2019, for a System CDR meeting taking place from December 9 to 12, 2019. This very tight and ambitious schedule is intended to force to have a Construction Proposal ready to be submitted to the first SKA Observatory Council meeting, in mid-June 2020. Meanwhile, element CDRs are progressing (with the SDP consortium having formally closed out actions and the AIV consortium having recently announced to have completed its planning work) and, as reported by the Interim Director of Operations (A. Chrysostomou), operation workshops were held in Cape Town and Perth between February and March 2019. Very importantly, an updated version of the SKA cost book and work breakdown structure were presented to the Board by J. McMullin, while I. Hastings (Head of Procurement Services) presented an update of the "Hybrid Procurement Model", consisting in a flexible approach, partly allocative and partly competitive.

- A. Russell (ESO), member of the Science And Engineering Advisory Committee (SEAC), presented the recommendation coming from the last face-to-face meeting (June 24-25, 2019) of this very important SKAO body, providing comments and useful inputs on the project status, the CDR developments (with particular attention the to SKA1-LOW telescope), the operation plan, and the SKA Regional Centers (SRC) organization work.

• 09 May 2019: An international group of scientists led by the University of Cambridge has finished designing the ‘brain' of the Square Kilometer Array (SKA), the world's largest radio telescope. When complete, the SKA will enable astronomers to monitor the sky in unprecedented detail and survey the entire sky much faster than any system currently in existence. 16)

- The SKA Science Data Processor (SDP) consortium has concluded its engineering design work, marking the end of five years' work to design one of two supercomputers that will process the enormous amounts of data produced by the SKA's telescopes.

- The SDP consortium, led by the University of Cambridge, has designed the elements that will together form the ‘brain' of the SKA. SDP is the second stage of processing for the masses of digitized astronomical signals collected by the telescope's receivers. In total, close to 40 institutions in 11 countries took part.

- The UK government, through the Science and Technology Facilities Council (STFC), has committed £100 m to the construction of the SKA and the SKA Headquarters, as its share as a core member of the project. The global headquarters of the SKA Organization are located in the UK at Jodrell Bank, home to the iconic Lovell Telescope.

- "It's been a real pleasure to work with such an international team of experts, from radio astronomy but also the High-Performance Computing industry," said Maurizio Miccolis, SDP's Project Manager for the SKA Organization. "We've worked with almost every SKA country to make this happen, which goes to show how hard what we're trying to do is."

- The role of the consortium was to design the computing hardware platforms, software, and algorithms needed to process science data from the Central Signal Processor (CSP) into science data products.

- "SDP is where data becomes information," said Rosie Bolton, Data Center Scientist for the SKA Organization. "This is where we start making sense of the data and produce detailed astronomical images of the sky."

- To do this, SDP will need to ingest the data and move it through data reduction pipelines at staggering speeds, to then form data packages that will be copied and distributed to a global network of regional centers where it will be accessed by scientists around the world.

- SDP itself will be composed of two supercomputers, one located in Cape Town, South Africa and one in Perth, Australia.

- "We estimate SDP's total compute power to be around 250 PFlops – that's 25% faster than IBM's Summit, the current fastest supercomputer in the world," said Maurizio. "In total, up to 600 petabytes (600 x 1015 bytes) of data will be distributed around the world every year from SDP –enough to fill more than a million average laptops."

- Additionally, because of the sheer quantity of data flowing into SDP: some 5 Tb/s, or 100,000 times faster than the projected global average broadband speed in 2022, it will need to make decisions on its own in almost realtime about what is noise and what is worthwhile data to keep.

- The team also designed SDP so that it can detect and remove manmade RFI (Radio Frequency Interference) – for example from satellites and other sources – from the data.

- "By pushing what's technologically feasible and developing new software and architecture for our HPC (High-Performance Computing) needs, we also create opportunities to develop applications in other fields," said Maurizio.

- High-Performance Computing plays an increasingly vital role in enabling research in fields such as weather forecasting, climate research, drug development and many others where cutting-edge modelling and simulations are essential.

- Professor Paul Alexander, Consortium Lead from Cambridge's Cavendish Laboratory said: "I'd like to thank everyone involved in the consortium for their hard work over the years. Designing this supercomputer wouldn't have been possible without such an international collaboration behind it."

• 08 May 2019: The prestigious German research organization the Max Planck Society has become the 13th member of the SKA Organization, following a unanimous vote by the SKA Board of Directors at its recent meeting at the SKA Organization Global Headquarters in the UK. 17)

- The Max Planck Society thus joins the final phase of the SKA Organization, which is overseeing the telescope design phase, until the process of transitioning into the SKA Observatory, an intergovernmental organization established by treaty to manage the construction and operation of the SKA, is completed. Any further German engagement, through joining the SKA Observatory, remains to be decided and will be subject to future discussions.

- "I am delighted to welcome the Max Planck Society to the SKA Organization as our 13th member, a deserved recognition of the significant contributions Germany has made to the SKA project over the years, and particularly in this crucial pre-construction phase," said Chairperson of the SKA Board of Directors Dr. Catherine Cesarsky.

- German research institutions and industry have been an intrinsic part of SKA-related projects since its earliest days, and have significant involvement in ongoing SKA design activities. In particular, the Max Planck Society provides instrumentation in the form of detectors, data acquisition and analysis systems for South Africa's world-class MeerKAT telescope, an SKA precursor facility which will become part of SKA's mid-frequency array (SKA-Mid).

- "I am extremely pleased to see our German colleagues consolidating their long-lasting involvement in SKA-related activities both at a scientific and industrial level", added Prof. Philip Diamond, SKA Director-General. "Germany's great wealth of expertise in radio astronomy, both in science and engineering, will continue to be invaluable as we move ever closer to SKA construction and operations."


Figure 10: Together with other German industries, MT Mechatronics of Mainz has developed the prototype elevation drive for the SKA-mid dishes(image credit: MTM)

- The Max Planck Society is a non-profit organization with 84 institutes and research facilities. In collaboration with other German institutions and industry, it has been involved across many areas of SKA design work, including within the Mid Frequency Dish Array, Low Frequency Aperture Array, Central Signal Processor, Science Data Processor, Telescope Manager, Signal and Data Transport consortia, and research and development work within the Phased Array Feeds and Wideband Single Pixel Feeds consortia.

- Among the Max Planck Society's institutes is the Max Planck Institute for Radio Astronomy (MPIfR) a key player in the SKA's Dish engineering consortium. Together with German industry partners, such as the telescope antenna specialists MT Mechatronics (MTM), and international partners, the Dish consortium is responsible for designing the SKA-Mid, to be deployed in South Africa. The Dish consortium has already delivered two prototype SKA dishes: SKA-P, which is currently being tested in China, and SKA-MPI (Max Planck Institute), funded by the Max Planck Society, which is under construction on the SKA site in South Africa's Karoo region.

- "The SKA is a great opportunity for astronomers, engineers, physicists and data scientists. Besides becoming an amazing discovery machine, SKA pushes the boundaries of what is technically possible, especially in the handling and analysis of huge amounts of data. The Max Planck Society is in the middle of all these exciting science and technology developments, and we are pleased to now be able to contribute officially to the SKAO (SKA Organization) efforts", says Prof Michael Kramer, director at the MPIfR, Bonn, Germany.

- The German science community has a long-held interest in the SKA project even beyond the radio astronomy field, as showcased in the 2012 German White Paper: Pathway to the Square Kilometre Array and in the "Denkschrift 2017: Perspektiven der Astrophysik in Deutschland 2017-2030", which is the German equivalent to the US Decadal Survey. The German community is also heavily involved in the SKA's Science Working Groups and Focus Groups and represented the third largest groups of authors in the 2000-page SKA Science Book: Advancing Astrophysics with the Square Kilometer Array, published in 2015.

- Germany has decades of experience in radio astronomy and is home to the Effelsberg 100 m Radio Telescope, the world's second-largest fully steerable radio telescope, located near Bonn. In operation since 1972, the 100 m dish has been continuously upgraded, developing and testing also SKA technology as MPIfR's flagship telescope. Germany also hosts six Low Frequency Array (LOFAR) stations, an SKA pathfinder facility which stretches across Europe.


Figure 11: The Max Planck Society has funded a second SKA prototype dish, SKA-MPI, currently being constructed on site in South Africa, bringing together Chinese, Italian and German components [image credit: SARAO (South African Radio Astronomy Observatory)]

• 12 March 2019: Countries involved in the SKA (Square Kilometer Array) Project have come together in Rome, Italy, for the signature of the international treaty establishing the intergovernmental organization that will oversee the delivery of the world's largest radio telescope. 18)

- Ministers, Ambassadors and other high-level representatives from over 15 countries have gathered in the Italian capital for the signature of the treaty which establishes the SKAO (Square Kilometer Array Observatory), the intergovernmental organization (IGO) tasked with delivering and operating the SKA.


Figure 12: The initial signatories of the SKA Observatory Convention. From left to right: UK Ambassador to Italy Jill Morris, China's Vice Minister of Science and Technology Jianguo Zhang, Portugal's Minister for Science, Technology and Higher Education Manuel Heitor, Italian Minister of Education, Universities and Research Marco Bussetti, South Africa's Minister of Science and Technology Mmamoloko Kubayi-Ngubane, the Netherlands Deputy Director of the Department for Science and Research Policy at the Ministry of Education, Culture and Science Oscar Delnooz, and Australia's Ambassador to Italy Greg French (image credit: SKA Organization)

- "Today we are particularly honored to sign, right here at the Ministry of Education, University and Research, the Treaty for the establishment of the SKA Observatory" Italian Minister of Education Marco Bussetti who presided over the event, said. "A signature that comes after a long phase of negotiations, in which our country has played a leading role. The Rome Convention testifies the spirit of collaboration that scientific research triggers between countries and people around the world, because science speaks all the languages of the planet and its language connects the whole world. This Treaty – he added – is the moment that marks our present and our future history, the history of science and knowledge of the Universe. The SKA project is the icon of the increasingly strategic role that scientific research has taken on in contemporary society. Research is the engine of innovation and growth: knowledge translates into individual and collective well-being, both social and economic. Participating in the forefront of such an extensive and important international project is a great opportunity for the Italian scientific community, both for the contribution that our many excellencies can give and for sharing the big amount of data that SKA will collect and redistribute"

- Seven countries signed the treaty today, including Australia, China, Italy, The Netherlands, Portugal, South Africa and the United Kingdom. India and Sweden, who also took part in the multilateral negotiations to set up the SKA Observatory IGO, are following further internal processes before signing the treaty. Together, these countries will form the founding members of the new organization.

- Dr. Catherine Cesarsky, Chair of the SKA Board of Directors, added "Rome wasn't built in a day. Likewise, designing, building and operating the world's biggest telescope takes decades of efforts, expertise, innovation, perseverance, and global collaboration. Today we've laid the foundations that will enable us to make the SKA a reality."

- The SKA will be the largest science facility on the planet, with infrastructure spread across three continents on both hemispheres. Its two networks of hundreds of dishes and thousands of antennas will be distributed over hundreds of kilometers in Australia and South Africa, with the Headquarters in the United Kingdom.

- Together with facilities like the James Webb Space Telescope, CERN's Large Hadron Collider, the LIGO gravitational wave detector, the new generation of extremely large optical telescopes and the ITER fusion reactor, the SKA will be one of humanity's cornerstone physics machines in the 21st century.

- Prof. Philip Diamond, Director-General of the SKA Organization which has led the design of the telescope added: "Like Galileo's telescope in its time, the SKA will revolutionize how we understand the world around us and our place in it. Today's historic signature shows a global commitment behind this vision, and opens up the door to generations of ground-breaking discoveries."

- It will help address fundamental gaps in our understanding of the Universe, enabling astronomers from its participating countries to study gravitational waves and test Einstein's theory of relativity in extreme environments, investigate the nature of the mysterious fast radio bursts, improve our understanding of the evolution of the Universe over billions of years, map hundreds of millions of galaxies and look for signs of life in the Universe.

- Two of the world's fastest supercomputers will be needed to process the unprecedented amounts of data emanating from the telescopes, with some 600 petabytes (600 x 1015 Bytes) expected to be stored and distributed worldwide to the science community every year, or the equivalent of over half a million laptops worth of data.

- Close to 700 million euros worth of contracts for the construction of the SKA will start to be awarded from late 2020 to companies and providers in the SKA's member countries, providing a substantial return on investment for those countries. Spinoffs are also expected to emerge from work to design and build the SKA, with start-ups already being created out of some of the design work and impact reaching far beyond astronomy.

- Over 1,000 engineers and scientists in 20 countries have been involved in designing the SKA over the past five years, with new research programs, educational initiatives and collaborations being created in various countries to train the next generation of scientists and engineers.

- Guests from Canada, France, Malta, New Zealand, the Republic of Korea, Spain and Switzerland were also in attendance to witness the signature and reaffirmed their strong interest in the project. They all confirmed they are making their best efforts to prepare the conditions for a future decision of participation of their respective country in the SKA Observatory.

- The signature concludes three and a half years of negotiations by government representatives and international lawyers, and kicks off the legislative process in the signing countries, which will see SKAO enter into force once five countries including all three hosts have ratified the treaty through their respective legislatures.

- SKAO becomes only the second intergovernmental organization dedicated to astronomy in the world, after ESO (European Southern Observatory).

• SKA Global Headquarters, 25 February 2019: The two engineering consortia tasked with designing all the essential infrastructure for the SKA sites in Australia and South Africa have formally concluded their work, bringing to a close nearly five years of collaboration both within and between the consortia. 19)

- Infrastructure Australia (INAU) and Infrastructure South Africa (INSA) were each led by institutions with great expertise in radio astronomy projects: Australia's CSIRO, which designed, built and operates the SKA precursor telescope ASKAP at its Murchison Radio-astronomy Observatory (MRO); and the South African Radio Astronomy Observatory (SARAO), which designed, built and operates the SKA precursor telescope MeerKAT. Industry partners also played key roles in both consortia*, while the European Union's Research and Innovation program Horizon 2020 awarded an additional €5M to conduct further work at both sites and at the SKA Global Headquarters in the UK.

Note*: Infrastructure Australia consortium members included the Commonwealth Scientific and Industrial Research Organization (CSIRO), Aurecon Australia and Rider Levett Bucknall. Infrastructure South Africa consortium members included the South African Radio Astronomy Observatory (SARAO), Aurecon South Africa and HHO Africa.

- The consortia were responsible for designing everything required to be able to deploy and operate the SKA in its two host countries, from roads, buildings, power, to RFI shielding, water and sanitation. Both CSIRO and SARAO developed valuable expertise from delivering the two precursor telescopes, which they applied to their work designing the SKA's site infrastructure.

- "This is the culmination of many years of development on both sites in preparation for the start of construction of the SKA," says Gary Davis, the SKA's Director of Operations Planning and chair of the review panel. "Both consortia have done a stellar job in collaboration with one another to design the crucial infrastructure that'll support the SKA."

- A major goal of the two consortia was to collaborate with each other in order to develop a common engineering approach, share knowledge and provide lessons learnt through the design and delivery of SKA precursors.

- "From the start we developed what we called the GIG, the good ideas group" says Ant Schinckel, Infrastructure Australia's Consortium Lead. "Our engineers would continuously engage with each other to discuss issues in both countries and find common solutions that could be applied to both sites" complements Tracy Cheetham, Infrastructure South Africa's Consortium Lead.

- "I'd like to thank both teams for their excellent work" said Martin Austin, the SKA's Infrastructure Project Manager "The quality of the design and their approach to safety means that we can now carry this work forward with a high degree of confidence, supported by both CSIRO and SARAO and their industry partners."

- INAU and INSA formed part of a global effort by 12 international engineering consortia, representing 500 engineers and scientists in 20 countries. Nine of the consortia focused on the SKA's core elements, while three others were tasked with developing advanced instrumentation.

- In 2018 and 2019 the nine consortia are having their Critical Design Reviews (CDRs), during which the proposed design must meet the project's tough engineering requirements to be approved, before a construction proposal for the SKA can be developed.

- In June and July 2018, both infrastructure consortia had successful CDRs and subsequently made the final refinements to their designs. With that work complete the consortia now formally disband, although the SKA will continue to work closely with former members in the months ahead as the overall System CDR approaches, to ensure that the infrastructure design aligns with all of the other components.


Figure 13: SKA's Infrastructure consortia completed their detailed design work for the SKA sites in 2018 (image credit: SKA Organization)

Figure 14: The Square Kilometer Array is an ambitious project to create a gigantic telescope from two enormous arrays of smaller antennas located in South Africa and Australia. The huge collecting area of the SKA will give it unprecedented sensitivity, enabling it to search for faint signals from far away sources. For SETI, it will be able to detect civilizations on other planets orbiting other stars, even if they are no more technologically advanced than our own civilization, and are not deliberately messaging us. — In this video, we sit down with some of the scientists and engineers who are spearheading the SKA project, at the SKA headquarters in Jodrell Bank, near Manchester, England (video credit: BerkeleySETI, Published on Aug 2, 2018)

• SKA Global Headquarters, 20 February 2019: The international Central Signal Processor (CSP) consortium has concluded its design work on the SKA, marking the end of five years' work comprised of 11 signatory members from 8 countries with more than 10 additional participating organizations. 20)


Figure 15: Members of the Central Signal Processor consortium at SKA Global Headquarters during the Critical Design Review in September 2018 (image credit: SKA Organization)

- The consortium, led by the National Research Council of Canada (NRC)*, has designed the elements that will together form the "processing heart" of the SKA. The CSP is the first stage of processing for the masses of digitized astronomical signals collected by the telescope's receivers. It's where the correlation and beamforming takes place to make sense of the jumble of signals, before the data is sent onwards to the Science Data Processor. At that stage, the data is ready to be turned into detailed astronomical images of the sky.

Note*: The CSP Consortium Project Management Office was led by a collaboration between the NRC and MDA, a contracted industry partner. Active consortium members (signatories) at the conclusion of the work included: Netherlands Institute for Radio Astronomy (ASTRON), Commonwealth Scientific and Industrial Research Organization (CSIRO) (Australia), Swinburne University of Technology (Australia), Max Planck Institute for Radio Astronomy (Germany), National Institute for Astrophysics (INAF) (Italy), New Zealand Alliance (AUT University, Massey University, University of Auckland, Compucon New Zealand and Open Parallel Ltd.), the Science and Technology Facilities Council (STFC) (UK), University of Manchester (UK), and University of Oxford (UK).

Figure 16: First impressions gathered after the Critical Design Review for the SKA's Central Signal Processor at the SKA's Global Headquarters in the UK (video credit: SKA Organization, published on 4 October 2018)

- The CSP includes the Pulsar Search and Timing sub-elements, which enable astronomers to detect and characterize pulsars and fast transients. This will facilitate the most comprehensive and ambitious survey yet to detect all pulsars in our own galaxy as well as the first extragalactic pulsars. The Pulsar Search sub-element is based on a hybrid architecture of Graphics Processing Units (GPUs) and Field Programmable Gate Arrays (FPGA) computing boards. The design team was led by the University of Manchester (UK), University of Oxford (UK) and the Max Planck Institute for Radio Astronomy (Germany) supported by input from INAF (Italy), New Zealand Alliance, STFC ATC Edinburgh (UK), and ASTRON (the Netherlands). The Pulsar Timing sub-element is based on GPUs. The design team consisted of participants from Swinburne University of Technology (Australia) and the New Zealand Alliance.


Figure 17: Low CBF (Correlation and Beam Forming) liquid-cooled Perentie Gemini Processing Board (left), Mid CBF Air-cooled TALON-DX Processing Board (right), image credit: SKA Organization

- As part of their work, the consortium designed the FPGA computing boards that will perform correlation and beamforming (CBF) on the signals from the SKA. The CBF for the SKA-mid telescope -to be located in South Africa- is based on Intel FPGA technology and was led by the NRC with support from MDA, a Maxar Technologies company, AUT University (New Zealand), and INAF. The CBF for the SKA-low telescope -to be located in Australia- is based on Xilinx technology, was led by CSIRO with support from ASTRON and AUT University. Hundreds of these boards are required to meet the demanding processing requirements.

- The Local Monitoring and Control sub-element was led by the NRC with contributions from MDA, INAF, and NCRA (India).

- The consortium was given a full pass by the review panel during the CSP Critical Design Review (CDR) in September, the first SKA engineering consortium to receive this result. With very few actions required following the review, the consortium has now concluded its work.

- "This is an extremely complex system – it has to process as many bits every 15 seconds as all the bits that are flowing through the global internet today," said Consortium Lead Luc Simard of the NRC. "That's a huge processing challenge at a site with limited electrical power and cooling power, and we have to fit a lot of hardware in a tight, restricted environment. To meet this challenge we needed a team of the highest quality – we have the best of the best and working with them has been a real honor. I'm really thankful for all their work."

- The consortium was formed in late 2013 as one of 12 international engineering consortia tasked with designing the SKA, a global effort representing 500 engineers in 20 countries. Nine consortia focused on core elements, while three developed advanced instrumentation for the telescope. The nine consortia are now at CDR stage, where an expert panel examines each design proposal against the SKA's stringent requirements.

- The consortium was formed in late 2013 as one of 12 international engineering consortia tasked with designing the SKA, a global effort representing 500 engineers in 20 countries. Nine consortia focused on core elements, while three developed advanced instrumentation for the telescope. The nine consortia are now at CDR stage, where an expert panel examines each design proposal against the SKA's stringent requirements.

- Now that its work is complete the consortium formally disbands, although the SKA Organization will work closely with participating countries to prepare for the overall System CDR and the development of the SKA construction proposal.

- "What made the design challenge so difficult are the exacting requirements for a telescope to deliver SKA telescope transformational science," said Philip Gibbs, SKA Organization Project Manager for CSP. "The system has to meet observing requirements that may include imaging, as well as VLBI, and pulsar search and timing, all at the same time. As well as the power and space issues on site, we've naturally also been constrained by the cost involved in providing a solution."

- "To reach this point is a testament to the tremendous effort of all the institutions involved in designing CSP – my heartfelt thanks go to them. We look forward to continued collaboration as we progress down the road towards construction of the SKA."


Australia Antenna Array

Under the joint hosting arrangements, Australia will host the SKA's low frequency aperture array antennas. 21)

In Phase 1, Australia will host over one hundred thousand antennas (each about 2 meters in height) covering low frequency radio waves, to be expanded to up to a million antennas in Phase 2. This array will conduct research into one of the most interesting periods of the Universe, looking back to the first billion years of the Universe to look at the formation of the first stars and galaxies, providing valuable insight into dark matter and dark energy and the evolution of the Universe.

It will provide an increased capability over existing infrastructure at the same frequencies, providing 25% better resolution and being 8 times more sensitive than LOFAR ( Low-Frequency Array) radio telescope, the current best such instrument. Moreover, it will be able to scan the sky 135 times faster. The sheer amount of raw data produced by all these antennas will be equivalent to five times the internet traffic.

ASKAP (Australian Square Kilometer Array Pathfinder) is CSIRO's (Commonwealth Scientific and Industrial Research Organization) radio telescope currently being commissioned at the Murchison Radio-astronomy Observatory (MRO) in Western Australia. Another important precursor for the SKA located in that region is the MWA (Murchison Widefield Array) 22) 23)

The MRO location is in a remote outback region about 350 km northeast from Geraldton in Western Australia. This follows the signing of an Indigenous Land Use Agreement (ILUA) with the Wajarri Yamatji Claimant Group. This region is ideal for a new radio observatory because the population density is very low and there is a lack of man-made radio signals that would otherwise interfere with weak astronomical signals.

Construction of ASKAP began in early 2010, and all 36 antennas, as well as site infrastructure, were completed in mid-2012. ASKAP is currently undergoing the fit-out of its complex PAF receiver systems and electronics, as well as commissioning.


Figure 18: The core of the Australian SKA activity is located at CSIRO's Murchison Radio-astronomy Observatory (MRO), and surrounding Mid West Radio-Quiet Zone in Western Australia. The MRO is already home to the ASKAP telescope, as well as another of the SKA precursors, the Murchison Widefield Array (MWA), image credit: ATNF

As part of SKA pre-construction, CSIRO is taking a lead role in a number of R&D consortia involved in the design and validation process of the SKA, including ‘Dish', ‘Infrastructure-Australia' and ‘Assembly, Integration and Verification'. The CSIRO SKA Center has also been established to coordinate and guide SKA activities within the organization.

Australia's existing 36 dish ASKAP telescope , each 12 m in diameter, is conducting groundbreaking research into new promising technologies for the SKA. Equipped with PAF (Phased Array Feed) technology, it will be able to survey large areas of the sky in great detail. The PAF for ASKAP provides the antenna with a wide FOV (Field of View) by creating 30 separate (simultaneous) beams to give a FOV of 30 º x 30º (the width of your little finger at arms length is around 1º), speeding up survey time quite considerably. 24)

ASKAP's rapid survey capability makes it one of the world's fastest survey radio telescopes. The PAF receivers have been specifically developed for ASKAP by CSIRO and this is the first time this type of technology has been used in radio astronomy. Traditional radio telescopes are good at providing a detailed view of a distant object. However, what astronomers often want is to study large volumes of space at once. With a traditional radio telescope, we can only do this by painstakingly looking in lots of different directions at different times. ASKAP can image (in 3D) large areas all at once, with much greater sensitivity than previous all-sky surveys. ASKAP has also been designed to be extremely fast - it will be able to detect millions of radio sources in a matter of days, opening new fields of research.

In addition to being a world-leading telescope in its own right, ASKAP is an important technology demonstrator for the SKA. ASKAP's home, the Murchison Radio-astronomy Observatory site will be the central site for major components of SKA telescope infrastructure in Australia.


Figure 19: ASKAP's ‘field of view' is depicted showing the 36 beams as individual circles. We get all of this in one go. By comparison, the field of view of a traditional telescope would be a single slightly smaller circle. The moon diameter is half the diameter of one of these circles (image credit:ATNF)

ASKAP specifications:

• Total collecting area of 4,000 m2, from 36 antennas, each 12 m in diameter

• System temperature less than 50 K

• Frequency range from 700 MHz to 1.8 GHz

• 300 MHz instantaneous bandwidth

• 36 independent beams, each of about 1º x 1º, yield overlapping to a 30º x 30º field-of-view at 1.4 GHz

• 6 km maximum baseline

• Full cross-correlation of all antennas

• Remote array station capability located in NSW, approximately 3,000 km from the core site.


Figure 20: Antennas of CSIRO's Australian SKA Pathfinder at the Murchison Radioastronomy Observatory in Western Australia (image credit: CSIRO, Steve Barker)


Figure 21: A phased array feed (PAF) receiver installed on an ASKAP antenna at the Murchison Radioastronomy Observatory (image credit: CSIRO, Barry Turner)


LFAA (Low Frequency Aperture Array)

The LFAA Element, a work package executed by the AADC (Aperture Array Design & Construction) Consortium, is one of the elements of the SKA1-LOW telescope and is defined as the antenna array stations, including the station signal processing, control and calibration. The work is set out in the Statement of Work agreed with the SKAO. 25)

The AADC Consortium team started working together in 2010 with a specific focus on SKA-LOW. Longer connections go back to SKADS, an EU FP6 project which started in 2005. The formation of the Consortium was therefore based on previous work and groups, which made it possible to move quickly to the actual realization and testing of prototypes. In particular Aperture Array Verification System 0.5 (AAVS0.5), was installed at the Murchison Radio Observatory as early as May 2013. This system has proven to be very valuable already (The initial LFAA specification sought to define an array capable of operating from 70-450 MHz).

The three SKA low-frequency pathfinders and precursor telescopes, LOFAR, NenuFAR and MWA, have been designed and realized and are currently operated by members of the AADC Consortium. The experience and knowledge gained is directly available for LFAA. Furthermore both LOFAR and MWA can be used as a test bed for new LFAA technology, this has already been proven to be very effective, most notably in the case of AAVS0.5 and MWA.

November 1st, 2013 marks the start of Stage 1 of the SKA1 preconstruction phase, to be finished in March 2015. The Preliminary Design Review (PDR) is a crucial milestone at the completion of Stage 1. As well as the design documents for PDR, intermediate deliverables have been generated and accepted. By the end of January, the AADC Consortium successfully passed its PDR!

In March 2015 the SKA members decided that SKA1-Low in Australia should be built. 50% of the planned 262,144 low frequency dipoles should be deployed. The array should cover the frequency range 50-350 MHz, as planned. The current planned baseline lengths of ~80km should be retained. The inclusion of a pulsar search capability for SKA1-Low (currently an Engineering Change Proposal on hold) should be actively explored.

The LFAA will be located in Australia, primarily in Western Australia. Observing frequencies in the 50- 350 MHz region, SKA-low will probe 13 billion years back in time to the period when the first stars and galaxies began to form. Phase 1 of SKA-low will deploy roughly 250,000 identical antennas and amplifiers. The array will be supported by local processing technology to combine the individual signals and transport them to the final supercomputing facility that will conduct final data processing and storage. 26)

The antennas have been designed to minimize cost and maximize ease of deployment and reliability in the remote environment. The core of the array will be tightly packed, with 75% of antennas located within a 2 km radius (at approximately 1.5m separation). The remaining antennas will form spiral arms spanning about 50 km to enhance final image detail.


Figure 22: An artist impression of the low frequency antennas in Australia with the ASKAP telescope in the background (image credit: CSIRO)