An ambition for the global astronomical community

Making the data produced by the rejuvenated Westerbork Telescope more open for, and delivered faster to, the astronomical community

Joeri van Leeuwen, Dutch astrophysicist, ASTRON and University of Amsterdam

Photography and text: Elodie Burrillon / HUCOPIX

Joeri van Leeuwen (42) is a Dutch astrophysicist at ASTRON (The Netherlands Institute for Radio Astronomy) and University of Amsterdam. In 2015, Joeri received a grant and in-kind expertise from the eScience Center for his project AA-ALERT, the Access and Acceleration of the Apertif Legacy Exploration of the Radio Transient Sky.

By collaborating with the eScience Center, Joeri’s team aims to make the new and enormous amount of data produced by the rejuvenated Westerbork telescope more open and delivered faster to everyone — and specifically to contribute to a better understanding of cosmic explosions.

Curiosity above all

Joeri: “I’ve always wanted to know how the things in the sky work”

Joeri: “I have always been very curious. As a child, I wanted to understand how animals function, how to make a big fire, how the things in the sky work. I remember liking astronomy when I was 17, but I was also drawn to other sciences. I am just inquisitive and want to know what makes things tick.”

Joeri van Leeuwen and Jisk Attema next to one of the radio telescopes at Westerbork
Joeri van Leeuwen on one of the 12 radio telescopes in Westerbork

Ending up at ASTRON

“After doing my PhD in astronomy in The Netherlands and spending a few years as a postdoc in Canada and the USA, I came back to The Netherlands ten years ago. I would say that ending up at ASTRON was a result of hard work but also a lot of luck: In my own country, just after finishing two postdocs, they were looking for astronomers to help build a huge radio telescope (LOFAR), with exactly the expertise I had been developing overseas.”

Being an astronomer

“As an astronomer, as in many scientific disciplines, you can focus on the theory, on observations, or on instrumentation. I enjoy that I do all three. Sometimes I work for months on a theory paper, sometimes I get my boots muddy at the LOFAR telescope.”

Signals received by the radio telescopes at Westerbork are transported via cables to the server room

“Our instruments involve a lot of computer science and high-performance computing, so often I am busy with the machines in the telescope server rooms. In addition, there are of course also the months I spend on attracting funding, or on the outreach I do. Plus the mentoring of a sizeable group of students and postdocs. That variety of tasks and skills I enjoy very much.”

The biggest challenge

“I think that the biggest challenge I ever had to overcome was getting ARTS, the real-time system on Apertif, built. The idea behind this project is to rejuvenate the Westerbork Telescope, making it a radio telescope with a 40 times bigger field of view than before, better than any other radio telescope. But the Dutch astronomical community runs many other world-class projects clamoring for resources. So, convincing all stakeholders (funding agencies, astronomers, politicians, technicians) to free up funding and person power took much energy and time. We made the first plans in 2010, and we are building it now.”

The rejuvenated radio telescope will have a 40 times bigger field of view, better than any other radio telescope

“I’m proud that ASTRON is the only institute in the world with two of the biggest radio telescopes — LOFAR and the Westerbork Telescope. And we are glueing these together through a real-time GPU supercomputing system.”

The AA-ALERT project

With Apertif accepted, Joeri could have been satisfied: there was now a real-time system, and an ERC award for a dedicated team of expert astronomers to help carry out the survey, ALERT. But he had an ambition for the global radio astronomical community: making these new data more open, and delivered faster.

Joeri: “Together with the eScience Center we teach new reflexes to an old telescope”

In 2015, Joeri received a grant from the eScience Center for his project AA-ALERT - the Access and Acceleration of the Apertif Legacy Exploration of the Radio Transient Sky. The team has a twofold aim: better access to the data produced by the Westerbork Telescope, and accelerated processing of this data.

Using our data shouldn’t be reserved to experts

“All our data is already open to everyone in principle, but to make it more open to everyone in fact, they need to be easily able to get and use it — using our data shouldn’t be reserved to experts.”

“This is the first half of the project: making the data more accessible to all. The second half concerns the acceleration of the decision-making. Apertif continuously produces so much data — more than the entire internet of The Netherlands, all the time — that it would be crazy to keep it all. So every second we have to decide ‘keep it’ or ‘throw it away’. So it’s a lot like building a new reflex for this telescope, telling it what to do.”

Collaborate with the eScience Center

“Collaborating with the eScience Center on this AA-ALERT project was, to me, almost obvious. Someone like eScience Research Engineer Alessio Sclocco worked with us on ARTS, at ASTRON, before he got a position at the eScience Center. The GPU acceleration he has been working on, only a handful of people in the country can do it. I actually wanted to hire him myself when he finished his PhD, but the eScience Center got him.”

Jisk Attema is an eScience Coordinator and works with Joeri on the AA-ALERT project

“In the meantime, Jisk Attema makes sure that, after a telescope reflex decision, astronomers can look at the relevant data for our science goals; understanding cosmic explosions. So you can imagine that what I value most about the eScience Center is the high level of expertise. Would I recommend working with the eScience Center? Well, a wholehearted ‘yes’!”