Flare-up in sunspot activity threat to satellites and electricity grid

By Keith Newman

Solar flare activity predicted for early next year could fry communication satellites and send vast sheets of geomagnetic electricity through the Earth, blowing transmitters and cutting power in some parts of the world.

While Transpower insists New Zealand is unlikely to have power outages as the result of the mounting cycle of solar storms, companies reliant on satellites have been warned to make alternative arrangements.

The half-cycle of sunbursts builds to a height every 11 years and reaches a full cycle every 22 years. The impact of magnetic storms after the cycle has reached its maximum is expected to be greater this time, largely because far more satellites have gone into orbit in the past 11 years.

There are now about 600, providing everything from telephone and data communication to pagers, global positioning systems and broadcast radio and TV coverage.

Telecom is confident it has enough capacity in its undersea cables if satellite communication is wiped out, but it admitted that services to the Pacific Islands, which is mainly provided by satellite, could be interrupted.

In March 1989, magnetic activity shut down the Hydro-Quebec power grid in Canada, leaving 6 million people without power for days.

Sky is preparing for the possibility of increased blackouts. It and other satellite broadcasters already face two outages for up to half an hour each year when the satellite orbit faces momentarily into the sun.

Optus has built its current generation of satellites to be more robust because it knew there would be increased solar activity during their lifetime. The company's New Zealand manager, John Humphries, said the satellites which covered Australia and New Zealand had built-in protection and were monitored round the clock.

However, there is growing evidence that even satellites built to withstand the sun's activity are at risk.

GE3, a General Electric satellite providing paging and public broadcasting services to North America, "went wacko" for three hours last week and nearly fell out of orbit. In January this year there was a problem with another "bird" and in May last year PanAmSat's Galaxy 4 satellite left 40 million pagers useless for four days, disrupted television and data broadcasts and blocked many credit card transactions.

Publisher and entrepreneur Bob Cooper, who runs his own satellite-based cable TV business in the Far North, said that in many cases the failure of the satellite was within 48 hours of an eruption on the sun.

He suggested the most damaging geomagnetic disturbance was likely to be between March 21 and September 21 when the sun was directly over the equator.

The highest sunspot activity on record was in March 1958, which reached an International Sunspot Number of 201 at the solar maximum, and in 1989 it hit 159. Sunspot activity had been expected to reach 190 in the current wave but Mr Cooper said it had waned.

"We're still on the upward slope and heading for about 145 on the scale by April next year. There's nothing insignificant about it," he said.

Anyone who depended on satellites needed a back-up plan.

While most major networks had extra satellites to cover for problems, several satellites being affected simultaneously could put the network down.

"For every three satellites over North America, there is one on stand-by. However, there are no stand-bys over Australia and New Zealand."

Professor Dick Dowden, a retired Otago University professor considered a national authority on space and radio physics, said sunspots increased relatively quickly and decayed slowly. They affected the ionosphere and could cause blackouts.

Magnetic storms, including charged particles, were emitted as a big wind and were affected by the earth's magnetic field, producing a current around and inside the earth's crust.

This could produce huge voltages, enough to affect power lines and transformers, he said.

However, Transpower spokesman Clive Bull, was confident that New Zealand was fairly safe. Measures to earth transmission towers had been taken in some parts of the country.

"It's a problem with very long east-west transmission systems. New Zealand has relatively short north-south transmission systems so we don't expect the same sort of problems they have in Canada and the US."