The observatory will provide a torrent of space data

SKA will be the world’s largest radio telescope and will generate over 700 PB of data per year. “We will be able to see how the first galaxies were created,” says John Conway at Onsala Space Observatory.

It is called the largest research facility that mankind will have built. Work is now beginning on the first stage of the Square kilometer array, or SKA observatory, and Swedish technology is playing an important role.

As early as 1991, researchers began sketching out the plans for a telescope with receivers that cover an area of ​​an entire square kilometer. After 30 years of idea work, the construction of SKA finally got the green light on June 29 this year and the procurement process can begin. Now ten years of work awaits to complete the first stage of the telescope.

– It is very exciting that SKA will eventually be built, and that Sweden can participate and contribute with fantastic technology, says John Conway who is professor of radio astronomy and director of Onsala space observatory at Chalmers who is Sweden’s representative in the SKA organization.

– It is a project that has been going on for a very long time. My supervisor when I received my doctorate was one of those who took part in developing the idea for SKA, and I hope to be able to participate in the inauguration just before I retire.

Read more: Spinlaunch has tested the accelerator that will throw up satellites

One of the first aerial parks in Australia. Over the next ten years, hundreds of these will be placed in the surrounding desert area. Photo: SKAO

700 petabytes of data per year

The huge observatory will already after the first stage is completed deliver over 700 petabytes of output per year. For John Conway, who studies black holes and how galaxies are formed, and many of his colleagues around the world, SKA will provide completely new opportunities to conduct research.

– It will completely change my field of research. We will be able to see how the first galaxies and black holes were created, says John Conway.

The telescope will be able to pick up radio waves from space much faster and with a much higher accuracy than ever before. Among other things, SKA will provide new opportunities for us to learn more about, among other things, dark matter and the evolution of galaxies and to provide an opportunity to test Einstein’s general theory of relativity.

– We use radio telescopes to investigate everything from nearby objects in our solar system to stars and galaxies and the gas fields between galaxies. Even the search for artificial signals that can come from extraterrestrial intelligent life. We will be able to see so much more with the help of SKA, says John Conway.

Read more: China’s space reactor beats Nasa by horsepower

One of the first full-size antennas installed in South Africa. Photo: SKAO

Hundreds of thousands of antennas

The plant consists of two parts on two different continents. In South Africa, there is the part of SKA that collects radio signals on the intermediate frequency bands (350 MHz to 14 GHz). Already today, there is a small observatory here, MeerKAT, which is a kind of precursor to SKA.

It will now be expanded from 64 to 197 satellite dishes during phase one of SKA. They will be spread over an area that extends over 150 km in the Karoo steppe area in southern South Africa.

In the first phase, the Australian part of the telescope will consist of 131,072 two-meter-high dipole antennas that will be placed in a desert area in Western Australia. The antennas are divided into 512 stations in the area. These should be used to read the lower frequency bands (50 MHz to 350 MHz).

Just like in South Africa, there are a couple of smaller facilities on site in Australia. These facilities have served as a test bed for the finished observatory.

– We do not start from scratch. The infrastructure is already there and now we know what it costs to build and operate this type of facility because there are already telescopes in place, says John Conway.

Read more: The Lund researchers ‘satellite measurements calculate countries’ carbon dioxide emissions

The research team at Onsala Space Observatory poses with a prototype for one of the recipients to be used in the SKA observatory. Photo: Johan Bodell

Swedish companies will deliver technology

Sweden contributes around SEK 170 million of the total construction cost of just over SEK 10 billion. In addition, Swedish technology uses several parts of the construction:

  • The largest radio receivers, known as Band 1, have been designed and tested at Onsala Space Observatory.
  • Low noise amplifier for three frequency bands has been developed by the Gothenburg company Low Noise Factory.
  • The Gothenburg company Qamcom has been involved in designing digital converters for the plant in South Africa.

Procurement for the finished products has begun shortly. As SKA designed it, Swedish companies will be able to deliver the technology in all three of these areas.

Each of the 14 member states will also contribute to managing the enormous amounts of data that the observatory will generate. In practice, each country will operate a data center for this purpose.

The proportion that each country should account for is approximately proportional to how many astronomers there are at the country’s universities. For Sweden, it will initially be about 11 petabytes of data that will be stored, analyzed and made available to researchers every year.

The first stage of SKA is expected to be completed by 2029. But there are already sketches of the final expansion, the one that actually provides a total square kilometer in receiver area.

Then it is a matter of expanding the Australian facility to over one million antennas, and in South Africa the number of dishes will be measured in thousands. They will be exhibited on an area that extends over 3,000 kilometers, so extensive that some nodes will need to be located in neighboring countries.

Read more: Solar winds and asteroid dust can be behind half of all water on earth

Low noise amplifier from the Gothenburg company Low Noise Factory. Photo: Johan Bodell

Increased computing power provides new opportunities

Even if the second stage would not be completed in a long time, it is also possible to expand the scope of SKA-1.

– The amount of data from SKA is not limited by the radio antennas, but by the computing power we have access to. If we had enough computing power, we could receive signals from each of the 130,000 antennas that SKA consists of, and in principle be able to observe the whole sky all the time, says John Conway.

The raw data from the antennas and satellite dishes is expected to exceed 15 terabits per second, but in the processing process, data is merged in several steps to reduce the flow in more manageable amounts.

If all raw data were forwarded to the local data centers, it would be tens of thousands of petabytes on an annual basis, instead of the 700 petabytes expected today.

The start of construction for SKA has been delayed several times during these 30 years, do you think the schedule will hold this time?

– There are no technical obstacles, it should more or less just be rolled out. What has held us back has been the political aspect of starting an international organization. It’s ready now, and the money has started to roll in. The procurements have begun. I am very optimistic that we will keep to the schedule, says John Conway.


Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.