eMerlin lays a pipeline to stars

The astronomers admired the roadside machinery as the drill bit negotiated its way a metre below the well-trimmed verges and neat gravel driveways.

Its ingenious design appealed to their problem-solving nature.

At the contraption's helm, Gary Kemp steered the drill on a course that would keep the residents of this quiet country lane calm.

It was the sort of careful job he had undertaken many times before. But this time, the fibre-optic cable Mr Kemp was laying through this corner of Cheshire would carry neither television pictures nor telephone calls.

As an element of the eMerlin radio telescope network, it will be alive with startling images from the distant edge of the universe.

Mr Kemp is intrigued at the prospect of laying a pipeline to the stars:

"This will get better pictures than Hubble," he mused.

Indeed, by next year eMerlin will give British astronomers one of the most powerful radio telescopes in the world.

The existing Merlin network of seven radio dishes includes the iconic Lovell Telescope at Jodrell Bank and stretches 217km from the Welsh borders to Cambridge. It has been at the cutting edge of astronomy since the 1980s.

The radio signals collected by each dish are almost entirely made up of a chaotic hiss, with maybe one part in a million coming from the celestial objects the scientists want to study.

Merlin strips away the noise to produce a coherent view of the universe by combining signals from its seven telescopes.

But its capabilities are handicapped by the amount of data handled by the radio links that connect the elements together.

Phil Diamond, director of Merlin, said just 0.5 per cent of the signal gets back to Jodrell Bank for analysis.

"These radio waves travel for billions of years from the edge of our universe, and in the last milliseconds of that journey we throw 99.5 per cent of the information away," he said.

The fibre-optic network that forms the backbone of eMerlin will end the waste. In the process, it will give astronomers a view of the heavens 30 times more sensitive than before.

Astronomy is led by observations. So while the scientists cannot predict what eMerlin will find, their excitement is obvious.

Simon Garrington, project manager, predicted there would be some great science as well as "breathtaking images" of the calibre that puts Hubble Space Telescope observations on the front pages of newspapers.

eMerlin's £7.6 million cost, met largely by Manchester University and the Northwest Development Agency, is small change compared with Hubble's billion-dollar price tag.

Nevertheless, the project has not had an easy ride with funding bodies.

"It has been tense at times," Professor Diamond admitted.

Even now, the astronomers are concerned that the £2.1 million a year it costs to run the project, provided by the Particle Physics and Astronomy Research Council, will restrict the function of the network and that a further £500,000 a year is required for smooth running.

Meanwhile, cable-laying teams are making eMerlin a reality.

Each telescope will need 30 gigabytes a second of bandwidth, with eMerlin handling 17 times more data than the UK's entire internet traffic.

Some 650km of fibre is needed, with the scientists taking control of two fibres in existing trunk cables provided by Global Crossing UK while Fujitsu Telecommunications' drills and cable-laying ploughs lay an extra 90km to complete the connections.

The work will also show the way to the creation of eMerlin's eventual successor - the Square Kilometre Array.

But until the SKA is built, some time near the start of the next decade, eMerlin will provide one of the best windows into the depths of the universe, all through the glint of a fibre-optic cable.