AuroraMAX / Canadian Space Agency
Is it "auroras" or "aurorae"? The dictionary prefers the former, but either way, there was a multiplicity of auroral awesomeness this weekend — thanks to a solar storm that swept past Earth's magnetic field over the weekend. During the past few days, we've shown off a few stunning images from Norway and Canada, and there's a new crop to share today.
First, a little explanation for what you're looking at:
Auroral lights arise when electrically charged particles from the sun interact with atoms and ions high up in Earth's atmosphere, 60 to 200 miles up. The interaction sets off emissions in wavelengths ranging from blue, to green (the most common color), to red. The colors depend on the energy of the particles in question. To get the full story on that, check out the explanations from the "Causes of Color" website and the University of Alaska at Fairbanks.
This weekend's auroras were particularly bright because of a strong solar outburst that occurred on Thursday. There's an interval between the outburst and the displays because the particles that are ejected from the sun travel at far less than the speed of light. But they're still pretty speedy — the velocity is on the order of a million miles an hour.
Solar outbursts, known more formally as coronal mass ejections or CMEs, have the potential to disrupt electrical grids or satellite communications. There could be radiation effects on astronauts in orbit or passengers on high-altitude, pole-traversing airplane flights. Thursday's outburst dealt Earth's magnetic field a glancing blow, and no significant negative impact has been reported. However, an even stronger CME is currently on its way toward Earth and may force the rerouting of polar flights. Once again, electric-grid managers and satellite operators will be on alert, as will aurora-watchers.
Observers in northern latitudes can look forward to enhanced auroras over the next couple of nights — and the rest of us can look forward to more images like these:
Bjorn Jorgensen's view of the aurora was captured on Sunday at Grotfjord, close to Tromso in north Norway. "This was amazing," he told SpaceWeather.com. "It was a wonderful experience to see these stunning auroras." The bird-of-prey picture was taken with a Nikon D3S camera equipped with a Nikkor 14-24mm lens. Exposure for the pictures in Jorgenson's set was ISO 2200 at five and six seconds. Check out SpaceWeather.com and ArcticPhoto.no for more views.
Chad Blakley / Lights Over Lapland
Chad Blakley said on Sunday that he had "an unbelievable night" at Sweden's Abisko National Park. "As soon as the sun went down I realized that we were about to experience something special," he told SpaceWeather.com. "The auroras have been dancing all night long and show no sign of stopping! I only came in because 32 gigabytes of memory cards were full and all three batteries were dead!" Click on over to Blakley's Vimeo page for a time-lapse video version of this imagery, and check out SpaceWeather.com for more from Abisko.
Chad Blakley / Lights Over Lapland
The auroral lights in Sweden were so bright that Chad Blakley could capture this view from the street. Blakley says his pictures were shot with a Nikon D7000 and a Tokina 11/16 lens at 2.8 with a 1600 ISO six-second exposure. For more of Blakley's images, check out the Lights Over Lapland website.
Adrian Jannetta and Emma Maddison
Adrian Jannetta took this picture of the auroral arc on Sunday night, about 2 miles west of Morpeth in the Northumberland region of England. "This is the first time I've photographed the aurora and the first time I've seen it since about 2004," he wrote on Flickr. The picture was taken using a Nikon D80 with 18mm lens, set for ISO 1250, f/3.5, 2x30sec exposures. For more auroral views from Jannetta, check his Flickr photostream.
The green glow of the aurora is reflected in a rock pool on the Emerald Isle, in Ireland's County Donegal. "The photo was taken at the end of my shoot as a last grab before heading home," photographer Gregory Clarke said in an email. "I climbed over some rocks to get to a rock pool, took a few test shots and then was treated to what I photographed. The photo was taken at Malin Head, County Donegal, using a Canon EOS Mk3. For that shot I bumped up the ISO to 1600 at f4, shot in RAW, and it seems to be the settings that worked for that shot." You'll find many more shots in Clarke's Flickr photostream.
The red and green auroral lights look like glowing curtains in Jason Ahrns' photo, captured near Fairbanks, Alaska, using a Nikon D5000 camera and an all-sky lens. You can see a time-lapse video that includes this still at Ahrns' Flickr gallery.
Marketa Stanczykova said she used a Canon 5D camera with a 17-40mm lens to take this picture of the northern lights dancing over Chatanika in Alaska. "I recently moved to Fairbanks," she said in an email. "My friends, photographers Ronn Murray and Casey Thompson (aurora chasers) took me close to Chatanika. It was an amazing night." For more of her pictures, check out this SpaceWeather.com page and this gallery from 500px.
More great auroral views:
- Northern lights go way, way south
- Speed through Lapland's lights
- Beautiful blasts from solar storms
- Get a video view of Canada's aurora
- Slideshow: The best of the northern lights
- Cosmic Log's auroral archive
Alan Boyle is msnbc.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter or adding Cosmic Log's Google+ page to your circle. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for other worlds.