Tuning in to 'radio Universe'

Astronomers at the School of Physical Sciences, University of Kent, have joined an innovative project that aims to address many of the key issues in astrophysics. These include: what is the universe made of and how does it evolve? Are we alone in the universe? How do galaxies, stars and planets form and evolve? What are the laws of physics in extreme conditions? And how does the sun affect the earth?

Such an undertaking will require the completion of arrays of antennas to detect radio waves at metre-long wavelengths. The low frequencies of these waves gives rise to the telescope by the name of LOFAR - the LOw Frequency ARray. The arrays will be spread across the Netherlands, Germany, France and Great Britain.

The processing of the data will be done by a supercomputer situated at the University of Groningen and further radio telescopes may be constructed at sites in Poland, Sweden, Ireland and Ukraine.

Michael Smith, Professor of Astrophysics at the University of Kent, said: 'The LOFAR project has been launched to advance upon instrumentation based on the old 1960s technologies of radio telescopes that used large mechanical dishes to collect signals which were then detected by a receiver for analysis.

'Even if scientists continued to use the old technologies, the instruments for this project would need to be one hundred times larger than existing ones, which is cost prohibitive as a high proportion of the outlay on these telescopes is the steel and moving structure. Therefore, new technology was required to make the next step in sensitivity necessary to unravel the secrets of the early universe, the physical processes in the centres of galaxies, and the formation of quasars, stars and planets.'

LOFAR is the first telescope of this new sort, using an array of simple omni-directional antennas instead of mechanical signal processing with a dish. The electronic signals from the antennas are digitised, transported to a central digital processor, and combined in software to emulate a conventional antenna.

University of Kent