As the biggest solar flare in four years was observed by NASA early Tuesday, the unusual and spectacular activity of the sun is likely to create another spectacle in the sky tonight - a display of northern lights, or aurora borealis.
An aurora is caused by the collision of charged particles directed by the Earth's magnetic field. As a result of natural mechanism, energy releases in the atmosphere are made visible to the naked eye in the form of colorful lights.
In the northern latitudes, the effect is known as the aurora borealis, or the northern lights. Auroras illuminate the northern horizon as a greenish glow or sometimes a faint red.
A display of northern lights is expected to be seen consecutively for three nights, and the show kicks off tonight.
An Associated Press story quotes NASA officials as saying the flare peaked early Tuesday. A cloud of charged particles erupted from the sun's outer atmosphere and is expected to pass by Earth late Wednesday or early Thursday, causing a minor disruption to Earth's magnetic field, the Associated Press quoted the National Weather Service's Space Weather Prediction Center in Boulder, Colorado.
The Aurora Borealis (Northern Lights) and Aurora Australis (Southern Lights) will likely be visible in the late hours of June 8.
The Geophysical Institute of the University of Alaska Fairbanks forecast auroral activity to be high tonight, with highly active auroral displays visible overhead from Barrow to Bethel, Dillingham and Ketchikan, and visible low on the horizon from King Salmon.
With the sun illuminating most of the auroral zone in Russia and Scandinavia, the aurora will be mainly visible in North America, according to the Institute. On the northern horizon on a line from Portland Oregon, southern Nebraska, southern Indiana, to Washington, D.C.
Visible auroral activities are predicted for Thursday and Friday as well, overhead from Inuvik, Yellowknife, Rankin, Igaluit and the surrounding areas. The visibility may be low on the horizon from Seattle, Des Moines, Chicago, Cleveland, Boston, and Halifax on Thursday, and Prince Rupert, Calgary, Minot, Bemidji, Stevens Point, Traverse City and Quebec City, Canada on Friday.
The northern lights can be viewed best in dark, clear skies. A grayish-green cloud, possibly with some reds and blues, may be observed, according to David Aguilar, director of information for the Harvard Smithsonian Center for Astrophysics. The lights can be photographed by putting a digital camera on a tripod with the lens wide-open on the infinity setting. The exposure rate must be adjusted manually to last for 5 to 10 seconds, Post-Gazette quoted Aguilar.