A Blog by International Students at Leiden University
*******Turn on your speakers for this one*******
This week started off with a field trip my class had been looking forward to for weeks. Our Radio Astronomy course ended last week and to give us a feel for techniques and theory we had been studying we travelled to the North of The Netherlands to Westerbork-Exloo-Dwingeloo.
It was my first road trip across the country and though I slept for most of the 2 hour journey up, every now and then I did make sure to get a glimpse of the beautiful countryside. We left Leiden at 9 and headed first to Westerbork which houses 14 telescopes in a linear array spread over a few kilometres.
As we walked along the array we heard stories about Westerbork. This place has both a sad and a bright side to it. During the war it used to be the site of a concentration camp which 100,000 Jews, homosexuals and Gypsies passed in transit on their way to execution in Germany. This part of Westerbork is now preserved as a memorial and to respect the sentiment attached visitors are requested to turn off their mobile phones (fair enough). We were there for the bright part though, to appreciate the magnificent facility that can observe distant objects in the Universe round the clock. It has been operational for over 40 years and is also serving as a testing site for the upcoming Square kilometre array to be built in South Africa.
In fact this juxtaposition sets the plot for the 1992 novel by the Dutch writer Harry Mulisch (died 2010) and in 2001 this was made into a film that stars the brilliant Stephen Fry. Many of the scenes were shot at the site of the telescopes and so naturally I found some advertisement in the form of this poster
Back in the day astronomers had to manually control a lot of the functions and data processing. These days one can operate from one’s bedroom. But some old school tech (notice the graph paper!) is still on display in the control room:
Our next stop was Exloo(close to the Dutch-German border) which is one of the many international sites for a special type of radio telescope network. These will eventually be replacing large metallic dishes and are simply configurations of antennae controlled by sophisticated electronics. This project is called LOFAR – (Low frequency array) and The Netherlands is a leader in the R&D involved.
A LOFAR antenna – yes we needed to change into boots as it was muddy, wet and freezing cold.
LOFAR from the skies (Source:Google :P)
By now we were quite tired with all the walking and were also hungry so we moved back into the bus munched into some sandwiches and made our way to our final destination which was at Dwingeloo – ASTRON – The Netherlands Radio Astronomy institute. Here we had a quick tour of the labs, had some coffee and then walked to another piece of history – The Dwingeloo telescope. It was inaugurated in 1956 by Queen Juliana and at 25 meters diameter was the biggest steerable telescope in the world at the time. It is sensitive to the famous 21 cm or 1420 MHz line which helps detect hydrogen.
Dwingeloo lay dormant for several decades but was very recently restored in a bid to preserve history and promote amateur astronomy. As a demonstration we had the telescope steered in the position of a pulsar – a very distant but strong radio source that emits radiation while rotating at high speeds. So please turn on your speakers now to listen to the heartbeat of a pulsar I recorded for you:
It was a long day moving from site to site involving long walks and even longer drives. So the hosts at ASTRON including our Leiden lecturer (also ASTRON director) had prepared a reception for us with plenty of food and drinks! I end with a group photo we took after devouring the snacks.
Must watch movie # 2
Okay for this week I suppose it would be appropriate to suggest watching ‘The discovery of heaven’ sticking to the theme of this blog and also since I haven’t watched it either. Would love to know if it’s any good.