A HUGE magnet destined for outer space left Oxfordshire this week with a police escort.

The £20m superconducting magnet, which weighs three tonnes, is a vital part of a scientific instrument which aims to uncover some of the secrets of the universe.

It was made by Scientific Magnetics, based at the Culham Science Centre, for the £1m Alpha Magnetic Spectrometer (AMS), a collaboration of 600 scientists and engineers from Europe, the US, China, Taiwan and Korea.

The company’s founders, Stephen Harrison, Stephen Milward and John Ross, set it up in 2000 specifically to make the AMS magnet after their previous employer, Oxford Instruments, decided not to go ahead with the project.

Sales director Peter Penfold said: “AMS will look at cosmic rays, which never make it through the earth’s atmosphere, so you have to go into space to study them. The scientists will look for experimental evidence to support their theories about the universe — for instance, they will look for evidence of anti-matter.”

The 3D software was supplied by another Oxfordshire company, Cutting Edge Solutions, of Leafield, near Witney.

The magnet arrived at Cern in Geneva on Tuesday, along with several Nasa scientists who have been on secondment in Culham.

Dr Penfold said: “Having taken all that time and money to build the magnet, we are taking every precaution to make sure it arrives safely in Cern.”

The AMS spectrometer will go to the European Space Centre in Holland for testing, and finally to Cape Canaveral in Florida. The experiment is too heavy for most spacecraft and will have to be taken up in the Nasa Shuttle, due to launch next year. It will then orbit the earth in the International Space Station.