No moving parts – a new kind of radio telescope

Murchison Widefield Array
The Murchison Widefield Array is one of the first telescopes with no moving parts. Credit: David Herne, ICRAR

Far outback in Western Australia, at the Murchison Radio Astronomy Observatory located on Boolardy Station, 315 km north-east of Geraldton, 32 tiles each carrying 16 dipole antennas have begun to collect scientific data on the Sun. At the same time they are providing engineering information to be used to extend the facility to a much bigger array of 512 tiles – the Murchison Widefield Array (MWA).

The MWA is designed to study radio sources at low frequencies, a poorly known part of the radio spectrum between 80 and 300 megahertz. It will be one of the world’s first telescopes without any moving parts. In fact, the array is “steered” electronically, which means the direction the telescope points depends entirely on how the signals from its stationary antennas are combined and processed.

The facility is a collaboration between several universities and research institutions in the US, Australia and India. The site for the full array will be prepared over six to nine months in 2010, and the MWA is scheduled to begin operating within a couple of years, says MWA Board member, Prof Steven Tingay of Curtin University of Technology in Perth, the International Managing Organisation for the $30 million telescope.

As the working tiles are being tested for the final array, so the MWA itself is testing technologies to be used when the world’s largest telescope, the Square Kilometre Array is built. But the MWA will be a powerful instrument in its own right, and already has been earmarked for three significant research projects:

  • the detection and analysis of hydrogen from the ‘Epoch of Re-ionisation’ in the early Universe when the gas changed from being almost neutral to extensively charged or ionised;
  • measurements of the Sun and material in the plasma surrounding it; and
  • a survey of low frequency radio emissions across the sky, particularly those that are transient.

For more information:

International Centre for Radio Astronomy Research
Steven Tingay
Tel: +61 (8) 9266 3516