Dancing northern lights attract space weather storm chasers

Edmonton resident Matt  took this photo from the Gibbons areas on Feb. 14, 2012.

Alberta heading towards major aurora borealis activity

EDMONTON - Edmonton residents can expect the spectacular as we head into a new period of activity for the northern lights.

Greens and reds in the night sky were so intense Valentine’s night they could be seen in downtown Edmonton. As the sun storms increase, we can hope to see a crescendo around the March equinox, says Ian Mann, who studies the phenomenon at the University of Alberta.

“We’ve been coming out of a very quiet period, in fact one of the quietest periods of the sun in the space age of the last 50 years,” Mann said.

But with three major light displays in quick succession — Jan. 25, Feb. 14 and Feb. 18 — it’s clear we are finally past that lull. After several years of relative quiet, light displays last week were seen and photographed as far south as Airdrie and Lethbridge.

“The forecast for the peak in solar activity is not until around the middle of 2013, so what we should have is continuing activity for the rest of this winter season,” Mann said. “Then next winter and the winter after that as well are going to be great opportunities.

“Statistically, the period around the equinoxes are the times when you see the best displays.”

Mann runs a free northern lights alert system at aurorawatch.ca that now has more than 10,000 subscribers.

The U of A has a station 40 kilometres east of Edmonton that measures variations in the local magnetic field. When the variations are strong, it automatically triggers an email red alert notifying subscribers about the lights two hours in advance.

The quietest years were between 2007 and 2009.

Matt Melnyk, a pilot for Can-west Air Charters, photographed the lights Feb. 13 while flying into Edmonton.

“We were on autopilot at 25,000 feet. You just stare out the window anyway,” said Melnyk, who also had a co-pilot in the fixed-wing air ambulance.

Melnyk shot the lights again Feb. 14 from the ground, driving out toward Gibbons after he got the email alert from Aurorawatch.ca. “They’re a lot of fun to take pictures of. April and March are really good months for it,” he said.

The northern lights, also called aurora borealis, are caused by electrons that rain down into the earth’s upper atmosphere. The electrons are guided by the magnetic field lines of the earth toward the north and south poles. They produce different colours of light when the electrons hit different elements of the atmosphere. That’s similar to how old TV sets sent electrons streaming across a cathode ray tube to hit different phosphors on the screen, creating a multi-coloured picture, Mann said.

The glow of the lights in the sky is actually about 110 to 250 kilometres high.

The peaks and lulls in activity follow the sun’s magnetic cycle. No one knows why, but it reverses magnetic polarity every 11 years, changing its north and south poles. Scientists can actually see this process happening in the form of sun spots, Mann said.

“The sun spots you see on the sun are little bundles of magnetic field that are poking out of the visible surface,” he said. “We can see the numbers of these change, their physical latitude migrates with time over the solar cycle.”

When many sun spots appear, more explosions occur on the sun sending blasts of energy 150 million kilometres toward the earth. It’s those weather storms that lead to spectacular displays of northern lights.

Many Edmonton residents who follow Mann’s alert system are what he calls space-weather storm chasers. They get an alert and head out of the city to see the lights better. Even going into a schoolyard can help.

University student Brent Kelly is one of those. “They’re like ribbons — changing, intermingling, growing,” he said.

They inspire awe, said Bill Werthman, co-founder of the Northern Lights Folk Club.

“I think just how insignificant I am,” Werthman said. “In a spiritual way without being religious, that’s what I think of when I see them.”

Mann said, “Big displays happen in bursts. You can see nothing happening for a long time sometimes, then suddenly there is a big release of energy.

“It can really pick up from something that looks like almost nothing or just a faint green glow to being one of these full sky spectacular dancing light shows.”