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Our friend Cory Schmitz planned the perfect time to go on a Iceland Aurora photo tour. With the recent activity from the Sun, there have been some great views of the aurora borealis in Iceland. “These images are very close to what the sky actually looked like to the naked eye,” Cory said on G+. “Motion, color, everything. Right above our heads. Insane — what an experience!”
Thanks for sharing the experience, Cory…. but next time, bring us with you, huh?
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Over the past several days the Sun has unleashed more than half a dozen major flares including four X-class events. The resulting aurora in some parts of the world have been beautiful. Here’s a collection of recent images taken by Jason Arhns in Alaska and one by Frank Olsen in Norway. In the image above, it seems the aurora is blanketing not only the sky, but the landscape as well!
See more below, as well as a video showing 23 of the 26 M- and X-class flares on the Sun between Oct. 23 and Oct. 28, 2013, as captured by NASA’s Solar Dynamics Observatory. It also shows the coronal mass ejections — great clouds of solar material bursting off the Sun into space — during that time as captured by the ESA/NASA Solar and Heliospheric Observatory.
How fun is this?! “Here’s a panoramic image from the aurora on October 14,” wrote Swedish astrophotographer Göran Strand. “I’ve made a small world trapped inside a bubble floating in space. And a lonely photographer is trying to capture the ongoing aurora with his camera.”
According to photographer Shawn Malone form Michigan, the aurora this fall have already been “insane!”
“We had a very strong auroral event here on October 2nd and 9th on Lake Superior in the Upper Peninsula of Michigan,” Malone said via email. “and what you are seeing in this video is the interaction of the solar wind impacting the magnetosphere at millions of miles per hour, that interaction causing the northern lights.”
These nights the aurora “really lit up,” said Malone.
And there could be more aurora coming soon to the northern skies: SpaceWeather.com is reporting that a coronal mass ejection propelled toward Earth by an M1-class eruption on October 13th is expected to hit our planet’s magnetic field on October. 15th. “Polar geomagnetic storms and high-latitude auroras are possible when the CME arrives,” says SpaceWeather.
Of course, not all aurora actually look like this to the human eye — you can read our article from earlier today about the reality of seeing aurorae with your eyes vs. a camera.
I shoot a lot of pictures of the northern lights. Just like the next photographer, I thrill to the striking colors that glow from the back of my digital camera. When preparing those images for publication, many of us lighten or brighten the images so the colors and forms stand out better. Nothing wrong with that, except most times the aurora never looked that way to our eyes.
The colors you see in aurora photos ARE real but exaggerated because the pictures are time exposures. Once the camera’s shutter opens, light accumulates on the electronic sensor, making faint and pale subjects bright and vivid. The camera can’t help it, and who would deny a photographer the chance to share the beauty? Most of us understand the magic of time exposures and factor in a mental fudge factor when looking at astronomical photos including those of the aurora.
But photos can be misleading, especially so for beginners, who might anticipate “the second coming” when they step out to watch the northern lights only to feel disappointment at the real thing. Which is too bad, because the real aurora can make your jaw drop.
That’s why I thought it would instructive to take a few aurora photos and tone them down to what the eye normally sees. Truth in advertising you know. I’ve also started to include disclaimers in my captions when the images show striking crimson rays. Veteran aurora watchers know that some of the most memorable auroral displays glow blood-red, but most of the ruddy hues recorded by the camera are simply invisible to the eye. Our eyes evolved their greatest sensitivity to green light, the slice of the rainbow spectrum in which the sun shines most intensely. We’re slightly less sensitive to yellow and only a 1/10 as sensitive to red.
A typical aurora begins life as a pale white band low in the northern sky. If we’re lucky, the band intensifies, crosses the color threshold and glows pale green. Deeper and brighter greens are also common in active and bright auroras, but red is elusive because are eyes are far less sensitive to it than green. Often a curtain of green rays will be topped off by red, blue or purple emission recorded with sumptuous fidelity in the camera. What does the eye see? Smoky, colorless haze with hints of pink. Maybe.
Again, this doesn’t mean we only see green and white. I’ve watched brilliant (pale) green rays stretch from horizon to zenith with their bottoms bathed in rosy-purple, a most wonderful sight. Another factor to keep in mind is dark adaption – the longer you’ve been out under a dark sky, the more sensitive your eyes will be to whatever color might be present. At night, however, we’re mostly color blind, relying on our low-light-sensitive rod cells to get around. Cone cells, fine-tuned for color vision, are activated only when light intensity reaches certain thresholds. That happens often when it comes to auroral green but less so with other colors to which our cells are less responsive.
Auroral colors originate when electrons from the sun spiral down Earth’s magnetic field lines like firemen on a firepole and slam into oxygen and nitrogen atoms in Earth’s upper atmosphere between 60 and 150 miles (96-240 km) high. Here’s a breakdown of color, atom and altitude:
* Green – oxygen atoms 60-93 miles up (100-150 km)
* Red – oxygen atoms from 93-155 miles (150-250 km)
* Purple – molecular nitrogen up to 60 miles (100 km)
* Blue/purple – molecular nitrogen ions above 100 miles (160 km)
When an electron strikes an oxygen atom for instance, it bumps one of the oxygen’s electrons to a higher energy level. When that electron drops back down to its previous rest or ground state, it emits a photon of green light. Billions of atoms and molecules, each cranking out tiny flashes of light, make an aurora. It takes about 3/4 second for that electron to drop and the atom to release a photon before it’s given another kick from a solar electron. Most auroras are rich with oxygen emission.
Higher up, where the air’s so thin it’s identical to a hard vacuum, collisions between atoms happen only about every 7 seconds. With lots of time on their hands, oxygen electrons can transition down to their lowest energy level inside the atom, releasing a photon of red light instead of green. That’s why tall rays often show red tops especially in time exposure photos.
Only during very active geomagnetic storms, when electrons penetrate to low levels in the atmosphere, are they able to excite molecules of nitrogen, giving rise to the familiar purple fringes at the bottoms of bright rays. Bombarded molecular nitrogen ions at high altitude release a deep blue-purple light. Rarely visible to the eye, I did record it one night in the camera.
While videos hint at how wildly dynamic auroras can be, they’re no substitute for seeing one yourself. That’s why I never seem to get to bed when that first tempting glow appears over the northern horizon. Colorful or colorless, you’ll be astonished at how the aurora constantly re-invents itself in a multitude of forms from arcs to rays to flaming patches and writhing curlicues. Don’t miss the chance to see one. If there’s one thing that looks absolutely unearthly on this green Earth, it’s the aurora borealis. Click HERE for a guide on when and where to watch for them.
Italian astronaut Luca Parmitano shares a lot of fantastic photos taken from his privileged position 260 miles up aboard the Space Station, orbiting the planet 16 times a day. This is his latest, a stunning view of nighttime city lights spread out beneath a glowing dome of ghostly airglow and shimmering aurorae, with a backdrop of brightly shining stars. The dark silhouette of a solar array is in the foreground at right.
And in case you were wondering, yes, astronauts certainly can see stars while in space. A lot of them, in fact. (Except up there, they don’t twinkle… but they’re no less beautiful!)
“Every time we look into the sky and we admire the same stars, we share the same experience with all those who still know how to dream.”
– Luca Parmitano
Luca Parmitano is the first of ESA’s new generation of astronauts to fly into space. The current mission, Volare, is ESA’s fifth long-duration Space Station mission. During his six-month-long stay aboard the ISS, Luca has been conducting research for ESA and international partners as well as taken many photographs of our planet, sharing them on Twitter, Flickr, and the Volare mission blog.
I’m writing this at 1:30 a.m. running on what’s powering the sky over northern Minnesota right now – auroral energy. Even at this hour, rays are still sprouting in the southern sky and the entire north is milky blue-white with aurora borealis. Frankly, it’s almost impossible to resist going out again for another look.
Now updated with additional images.
The arrival of a powerful solar wind in excess of 375 miles per second (600 km/second) from a coronal mass ejection shocked the Earth’s magnetic sheath last night beginning around 9 p.m. CDT. The sun’s magnetic field, embedded in the wind, pointed sharply southward, allowing eager electrons and protons to worm their way past our magnetic defenses and excite the atoms in the upper atmosphere to glow. Voila! Northern lights.
Sure, it started innocently enough. A little glow low in the northern sky. But within half an hour the aurora had intensified into a dense bar of light so and green and bright it cast shadows. This bar or swath grew and grew like some atomic amoeba until it swelled beyond the zenith into the southern sky. Meanwhile, an isolated patch of aurora glowed like an green ember beneath the Pleiades in the northeastern sky. The camera captured its eerie appearance as well as spectacular curtains of red aurora dancing above the dipper-shaped cluster.
Soft patches, oval glows and multiple arcs lit up the north, east and west, but in the first two hours of the display I never saw a ray or feature with any definition. The camera recorded a few but all was diffuse and pillowy to the eye. Rays finally made their appearance later – after midnight and later – when they massed and surged to the zenith and beyond.
Then came the flickering, flame-like patches and snaky shapes writhing lifelike across the constellation Pegasus during the phase called the coronal aurora. That’s when all the curtains and rays gather around the local magnetic zenith. As they flicker and flame, their shapes transform into eagle wings and snakes wriggling across the stars.
Funny, the space weather forecast called for quiet conditions last night and for the next two nights. But the eruption of a large filament, a tubelike region of dense hydrogen gas held aloft in the sun’s atmosphere by magnetic fields, sent a bundle of subatomic joy in Earth’s direction a bit earlier than expected. More auroras are possible tonight and tomorrow night as the effect of the shock wave continues. Despite the U.S. government shutdown, the Space Weather Prediction Center remains open.
There are so many ways to appreciate the aurora but my favorite is simply to stand there dumbfounded and try to take it all in. Few phenomena in nature are more deeply moving.
UPDATE: Other astrophotographers in the US also were able to capture some aurora images. John Chumack, whose images we frequently feature here on UT got this shot early on the morning of October 2:
And Alan Dyer in Canada got this amazing “fiery” shot:
This timelapse from Arthur, Ontario was shot on Oct. 2 as well:
Frank Olsen reports that the weather in arctic part of Norway has been fantastic lately. Even so, the aurora are starting to make nightly appearances.
“I was standing on the very tip of an island in Vesterålen with a spectacular view, looking out on the Atlantic ocean,” he said. “With the full moon behind me, the clouds were amazing.”
Clouds mixed in with the aurora made for some lovely views. In all, Frank said he nabbed almost 400 images on his memory card! See another shot, below.
As we’ve said previously, these gorgeous sights must be payback for enduring the long winters in northern Norway. You can see more of Frank’s beautiful imagery of aurora, the night sky and more at his Flickr page, his website (he has prints for sale) or his Facebook page.
Want to get your astrophoto featured on Universe Today? Join our Flickr group or send us your images by email (this means you’re giving us permission to post them). Please explain what’s in the picture, when you took it, the equipment you used, etc.
As an amateur astronomer, two of the most frequently questions I’m asked are “When is the best time to see the aurora borealis and where is the best place?” In terms of place, two locations comes to mind: Churchill, Manitoba and Tromso, Norway. But until such time as the transporter is invented, most of us will be staying closer to home. The simple answer is north and the farther north the better.
As for the time, in the northern border states of the US, auroras occur fairly regularly around the time of solar maximum, when the sun peaks in storm activity. The current solar cycle tops out this summer and fall, so your chances at seeing northern lights are far better now than a year and a half ago when solar activity saw a steep decline during a protracted minimum.