Mobile phone blinds the stars

Mobile phones are posing a threat to astronomers' research into the Big Bang and the death of stars.

The next generation of phones is to use a low-orbit satellite network which has several frequency bands crucial to both astronomers and telecommunications.

Astronomers warn that mobile phone interference could endanger up to a half of all radio astronomy.

At the University of Manchester's Jodrell Bank radio telescope, three of seven frequencies used are wholly or partly threatened.

But James Cohen, reader in radioastronomy at Jodrell Bank, said India could suffer the most.

It is just completing the Giant Metre Wave Radio Telescope, which is intended to search for signs of the formation of galaxies.

"They are very proud of the way they have done it," he said.

The telescope was built in a remote area but will not be able to escape the satellites, which will enable any mobile phone or other electronic equipment to communicate anywhere else in the world.

"This instrument is going to be under attack from almost every system that is planned. They are really worried about it," he said.

Dr Cohen, whose worries are set out in the new Handbook on Radio Astronomy, to be published later this month by the European Science Foundation, said that astronomers want to see certain frequencies for their use only.

But he said that the main problem is leakage from one frequency band to another. There are no regulations to limit leakage, which would require expensive alterations to equipment.

At present, radio astronomy frequency bands are guaranteed by the International Telecommunications Union, "but interference is a growing problem which the ITU appears reluctant to recognise," says the handbook.

The next battle over allocations will happen at a November ITU meeting, which aims to find more frequencies for the industry and where radio astronomers will have to take on the giants of the telecom industries.

A similar problem arose when global navigation systems were put in place. This is being solved by putting extra filters on the satellites and negotiating over frequency bands.