Aurora borealis shines again in Alberta skies

It's been just over three weeks since Albertans saw an unusually bright aurora borealis shine over their skies on Oct. 12 and early Thursday morning, they got another spectacular display.

These displays werecourtesy of a moderate geomagnetic storm, according to the U.S.National Oceanic and Atmospheric Administration. Geomagnetic storms are changes in the Earth's magnetic fieldcaused by solar flares.

AuroraMAX,a federally-funded observatory in Yellowknife, N.W.T., said in a Facebook post on Wednesday that the northern lights would be visible in most provinces and territories on Nov. 3 and 4. There was some activity seen Wednesday evening in Alberta, but it was more prominent after midnight.

There was also a display across parts of Canada on the weekend of Oct. 30 and 31.

The aurora borealis happens when particles from the sun are carried toward the planet's ionosphere, and those particles collide with gas particles,releasing energy that's visible as light.

Auroras are usually seen only in polar regions, but particularly large bursts of solar energy or coronal ejections have caused the aurora to be seenmuch farthersouth than usual.

If you're looking for something to brighten your day, here are some photos of the aurora on Thursday morning that Albertans shared with CBC Calgary.

If you missed them, here are also some photos we shared a few weeks ago from the northern lights displayon Oct. 12.