VA6DJB
08-25-2005, 12:54 PM
OTTAWA — A major geomagnetic storm washed over Canada early Wednesday and a second smaller event was forecast for early Thursday, providing a light show for sky watchers and potential headaches for satellite companies.
"It's up at the high end, this one -- this is up in the major storm category," said David Boteler, a scientist with Natural Resources Canada.
A large sun spot Monday afternoon sent a wave of electrons and protons screaming through space at 1,644 kilometres a second -- four to five times the usual speed.
"That plowed into the Earth just after midnight (Wednesday)," said Boteler, who works with the Geological Survey of Canada tracking such events. "I'd expect for anyone up to see it, there would have been some very good auroral displays."
A second large eruption on the sun's surface Tuesday was approaching Earth on Wednesday night.
Geomagnetic storms are caused by gusts of solar wind blowing past Earth and disturbing the planet's protective magnetic field, mainly around the North and South poles.
Such storms can affect electrical grids, satellite communications and high frequency radio transmissions -- while also providing spectacular displays of the northern lights far south of where the aurora borealis normally rings the top of the globe.
"When you get a large disturbance like this, then the whole of that ring expands so that brings the aurora and the magnetic activity down to lower latitudes," said Boteler.
Other effects are less benign.
In March 1989, a severe geomagnetic storm knocked out Quebec Hydro's grid from James Bay to Montreal, cutting power to almost six million people.
In 1994, a similar storm destroyed circuits in the $296-million Anik E-1 satellite, disrupting Canadian TV, radio and data transmissions.
Two years later, yet another geomagnetic storm affecting American satellites caused a massive break in pager service in the United States. And in 2003, a storm briefly cut power to 20,000 people in Sweden.
The Geological Survey of Canada, which provides forecasts of solar activity on the Natural Resources Canada website, had no reports Wednesday of damage from the latest event.
Power grids have been upgraded since 1989 to protect them from geomagnetic surges and some changes have been made to protect the hundreds of satellites orbiting Earth.
Satellites, however, remain exposed, said Boteler. In fact, some are more vulnerable today than in the past because electronics advances have moved to low-power circuitry that can have less tolerance for sudden power surges.
Overall sun spot activity is in decline, on the downswing of an 11-year cycle. But that hasn't stopped what Boteler describes as "almost rogue storms" that have washed the Earth in the past two years.
"These very large ones are rather unpredictable," said the scientist.
"It's up at the high end, this one -- this is up in the major storm category," said David Boteler, a scientist with Natural Resources Canada.
A large sun spot Monday afternoon sent a wave of electrons and protons screaming through space at 1,644 kilometres a second -- four to five times the usual speed.
"That plowed into the Earth just after midnight (Wednesday)," said Boteler, who works with the Geological Survey of Canada tracking such events. "I'd expect for anyone up to see it, there would have been some very good auroral displays."
A second large eruption on the sun's surface Tuesday was approaching Earth on Wednesday night.
Geomagnetic storms are caused by gusts of solar wind blowing past Earth and disturbing the planet's protective magnetic field, mainly around the North and South poles.
Such storms can affect electrical grids, satellite communications and high frequency radio transmissions -- while also providing spectacular displays of the northern lights far south of where the aurora borealis normally rings the top of the globe.
"When you get a large disturbance like this, then the whole of that ring expands so that brings the aurora and the magnetic activity down to lower latitudes," said Boteler.
Other effects are less benign.
In March 1989, a severe geomagnetic storm knocked out Quebec Hydro's grid from James Bay to Montreal, cutting power to almost six million people.
In 1994, a similar storm destroyed circuits in the $296-million Anik E-1 satellite, disrupting Canadian TV, radio and data transmissions.
Two years later, yet another geomagnetic storm affecting American satellites caused a massive break in pager service in the United States. And in 2003, a storm briefly cut power to 20,000 people in Sweden.
The Geological Survey of Canada, which provides forecasts of solar activity on the Natural Resources Canada website, had no reports Wednesday of damage from the latest event.
Power grids have been upgraded since 1989 to protect them from geomagnetic surges and some changes have been made to protect the hundreds of satellites orbiting Earth.
Satellites, however, remain exposed, said Boteler. In fact, some are more vulnerable today than in the past because electronics advances have moved to low-power circuitry that can have less tolerance for sudden power surges.
Overall sun spot activity is in decline, on the downswing of an 11-year cycle. But that hasn't stopped what Boteler describes as "almost rogue storms" that have washed the Earth in the past two years.
"These very large ones are rather unpredictable," said the scientist.