ASTRON develops heart of new supercomputer for world’s largest radio telescope

ASTRON, the Netherlands institute for radio astronomy, has developed the heart of the new supercomputer for the Square Kilometre Array (SKA), the future largest and most sensitive radio telescope in the world. On 4 June, ASTRON presents this heart, the computer board called Gemini, to Ingrid van Engelshoven, the Dutch Minister of Education Culture and Science, during an introductory visit in Dwingeloo, the Netherlands.

Published by the editorial team, 6 April 2018

The Square Kilometre Array (SKA) is a new radio telescope built by an international collaboration in Western Australia and South Africa. In Australia, the telescope will consist of 130,000 small antennas spread over 512 antenna fields. The design is based on ASTRON's Low Frequency Array (LOFAR) in Drenthe, the Netherlands. With all these antennas, SKA will generate enormous amounts of data: one petabit per second – more than three times the global internet traffic in 2018.

ASTRON is working with the Australian research institute CSIRO (Commonwealth Scientific and Industrial Research Organisation) to develop the heart of the supercomputer, the computer board Gemini, which will process the data in Western Australia. Thanks to Gemini, it is now possible to combine the thousands of antennas into one large telescope, which is crucial for the astronomical research of SKA."It is wonderful that all SKA data in Australia will soon be processed by Dutch technology. ASTRON plays a leading role on the world stage of radio astronomy. We can be very proud of that", says minister Van Engelshoven.

The presentation of the Gemini board to minister Van Engelshoven by Gijs Schoonderbeek (instrument engineer at ASTRON) and Paula Fusiara (mechanical engineer at ASTRON).

Huge amounts of data

Gemini is a computer board containing the newest processor from the company Xilinx Inc., also called a Field Programmable Gate Array (FPGA). This allows it to process vast amounts of data continuously. In order to process and combine all data streams from SKA in Australia, a supercomputer is ultimately made with a total of 288 Gemini boards. "After combining the data per antenna field, the supercomputer has to process a total of 5.8 Terabit per second of data. That is why these boards with efficient processors are necessary", explains ASTRON engineer Gijs Schoonderbeek. "For comparison: the Amsterdam Internet Exchange, the largest internet hub in the Netherlands, has an average data flow at the entrance of 3.4 Terabit per second."



The Gemini board.

Water cooling

For Gemini, a lot of energy is needed that is converted into heat. In order to optimally cool the processor, ASTRON has developed a special water block. "The water drains the heat directly from the processor to a cool place deep under the ground of the Australian desert," says Schoonderbeek. "In this way we cool the processor more optimally than with traditional air cooling. An additional advantage is that the energy consumption is lower when the processor is cooler."

Large production

For the production of the 288 Gemini boards, ASTRON works closely with the company Neways Electronics in Leeuwarden, the Netherlands. "Thanks to this collaboration, we are creating a design that, despite the complexity, can be produced in large numbers", says Schoonderbeek. "The programming of the specialised processor is done in collaboration with CSIRO and the Auckland University of Technology in New Zealand."

Text: Iris Nijman


Latest tweets

Daily image of the week

On June 13-17, the LOFAR Family Meeting took place in Cologne. After two years LOFAR researchers could finally meet in person again. The meeting brings together LOFAR users and researchers to share new scientific results.

Our renewed ‘Melkwegpad’ (Milky Way Path) is finished! The new signs have texts in Dutch on the one side and in English on the other side. The signs concerning planets have a small, 3D printed model of that planet in their centre.
#Melkwegpad @RTVDrenthe

Daily image of the week

The background drawing shows how the subband correlator calculates the array correlation matrix. In the upper left the 4 UniBoard2s we used. The two ACM plots in the picture show that the phase differences of the visibilities vary from 0 to 360 degrees.

Daily image of the week: Testing with the Dwingeloo Test Station (DTS)
One of the key specifications of LOFAR2.0 is measuring using the low- and the highband antenna at the same time. For this measurement we used 9 lowband antenna and 3 HBA tiles.