Posted on by Ken Kremer

Spectacular Earth Timelapse Video: Christmas Gift from Alexander Gerst’s 2014 ISS Voyage

Another new snapshot of Earth’s “beautiful Southern Lights” taken from the ISS on 5 July 2014. Credit: ESA/Alexander Gerst

Video Caption: Watch the Earth roll by through the perspective of German astronaut Alexander Gerst in this 4K six-minute timelapse video of images taken from on board the International Space Station (ISS) during 2014. Credit: Alexander Gerst/ESA

ESA astronaut Alexander Gerst from Germany who recently returned from a six month voyage to the International Space Station (ISS) has a special Christmas gift for all – a stunning six-minute timelapse compilation of his favorite images of Earth taken during his “Blue Dot” mission in 2014.

“A 4K timelapse showing our planet in motion, from my favourite Earth images taken during the Blue Dot mission,” wrote Gerst in connection with his spectacular timelapse video released to coincide with Christmastime.

“I wish all of you a merry Christmas! It was a wild year for me, thanks for joining me on this fascinating journey!” said Gerst in English.

“Wünsche euch allen fröhliche Weihnachten! War ein wildes Jahr für mich, vielen Dank, dass ihr mit dabei wart!” said Gerst in German.

You can watch the Earth roll by through Gerst’s perspective in this six-minute timelapse video combining over 12,500 images taken during his six-month mission aboard the ISS that shows the best our beautiful planet has to offer.

“Marvel at the auroras, sunrises, clouds, stars, oceans, the Milky Way, the International Space Station, lightning, cities at night, spacecraft and the thin band of atmosphere that protects us from space,” according to the video’s description.

Gerst would often would set cameras to automatically take pictures at regular intervals while doing his science research or preparing for the docking of other spacecraft at the ISS in order to get the timelapse effect shown in the video.

“Scary. The sunlight is far from reaching down the abyss of Neoguri's 65 km-wide eye.” Taken from the ISS on 8 July 2014. Credit: ESA/NASA/Alexander Gerst
“Scary. The sunlight is far from reaching down the abyss of Neoguri’s 65 km-wide eye.” Taken from the ISS on 8 July 2014. Credit: ESA/NASA/Alexander Gerst

The robotic arm capture and berthing of the SpaceX Dragon cargo ship and the release of the Orbital Sciences Cygnus cargo freighter are particularly magnificent in a rarely seen timelapse glimpse of visiting vehicles that are absolutely essential to keeping the station afloat, stocked, and humming with research activities.

Gerst served aboard the ISS between May and November this year as a member of the Expedition 40 and 41 crews.

Gerst launched to the ISS on his rookie space flight on May 28, 2014, aboard the Russian Soyuz TMA-13M capsule along with Russian cosmonaut Maxim Suraev and NASA astronaut Reid Wiseman.

They joined the three station flyers already aboard – cosmonauts Alexander Skvortsov & Oleg Artemyev, and astronaut Steve Swanson – to restore the station crew complement to six.

Gerst and Wiseman became well known and regarded for their prolific and expertly crafted photography skills.

ESA astronaut Alexander Gerst, Russian commander Maxim Suraev and NASA astronaut Reid Wiseman returned to Earth on 10 November 2014, landing in the Kazakh steppe. Credit: ESA–S. Corvaja
ESA astronaut Alexander Gerst, Russian commander Maxim Suraev, and NASA astronaut Reid Wiseman returned to Earth on 10 November 2014, landing in the Kazakh steppe. Credit: ESA–S. Corvaja

They returned to Earth safely on Nov. 10, 2014, with a soft landing on the Kazakh steppes.

Alex is Germany’s third astronaut to visit the ISS. He conducted a spacewalk with Wiseman on Oct. 7 while aboard. He is trained as a geophysicist and a volcanologist.

ESA astronaut Alexander Gerst spent six hours and 13 minutes outside the International Space Station with NASA astronaut Reid Wiseman on Tuesday, 7 October 2014. This was the first spacewalk for both astronauts but they performed well in the weightlessness of orbit. Credit: NASA/ESA
ESA astronaut Alexander Gerst spent six hours and 13 minutes outside the International Space Station with NASA astronaut Reid Wiseman on Tuesday, 7 October 2014. This was the first spacewalk for both astronauts but they performed well in the weightlessness of orbit. Credit: NASA/ESA

Read my story detailing Christmas 2014 festivities with the new crews at the ISS – here.

Stay tuned here for Ken’s continuing Earth and planetary science and human spaceflight news.

Ken Kremer

Posted on by Tim Reyes

Solved: The Mystery of Earth’s Theta Aurora

From the ground, aurora have mystified humans since we began to question the world. The space age revealed more mystery - the Theta Auroral Oval (inset) and the challenge of understanding the phenomena. (Photo Credit: NASA/APOD)

The mystery of the northern lights – aurora – spans time beyond history and to cultures of both the southern and northern hemispheres. The mystery involves the lights, fantastic patterns and mystical changes. Ancient men and women stood huddled under them wondering what it meant. Was it messages from the gods, the spirits of loved ones, warnings or messages to comfort their souls?

Aurora reside literally at the edge of space. While we know the basics and even more, we are still learning. A new published work has just added to our understanding by explaining how one type of aurora – the Theta Aurora – is created from the interaction of the charged particles, electric and magnetic fields surrounding the Earth. Their conclusions required the coordination of simultaneous observations of two missions.

The Theta Auroral Oval as observed by the NASA IMAGE FUV camera on September 15, 2005. (Credit: NASA/SWRI)
The Theta Auroral Oval as observed by the NASA IMAGE FUV camera on September 15, 2005 and anlayzed using Cluster data in the paper by Fear et al. (Credit: NASA/SWRI)

We were not aware of Thetas until the advent of the space age and our peering back at Earth. They cannot be recognized from the ground. The auroras that bystanders see from locales such as Norway or New Zealand are just arcs and subsets of the bigger picture which is the auroral ovals atop the polar regions of the Earth. Ground based all-sky cameras and polar orbiting probes had seen what were deemed “polar cap arcs.” However, it was a spacecraft Dynamics Explorer I (DE-1) that was the first to make global images of the auroral ovals and observed the first “transpolar arcs”, that is, the Theta aurora.

They are named Theta after the Greek letter that they resemble. Thetas are uncommon and do not persist long. Early on in the exploration of this phenomenon, researchers have been aware that they occur when the Sun’s magnetic field, called the Interplanetary Magnetic Field (IMF) turns northward. Most of the time the IMF in the vicinity of the Earth points south. It is a critical aspect of the Sun-Earth interaction. The southerly pointing field is able to dovetail readily with the normal direction of the Earth’s magnetic field. The northward IMF interacting with the Earth’s field is similar to two bar magnets turned head to head, repelling each other. When the IMF flips northward locally, a convolution takes place that will, at times, but not always, produce a Theta aurora.

A group of researchers led by Dr. Robert Fear from the Department of Physics & Astronomy, University of Leicester, through analysis of simultaneous spacecraft observations, has identified how the particles and fields interact to produce Theta aurora. Their study, “Direct observation of closed magnetic flux trapped in the high-latitude magnetosphere” in the Journal Science (December 19, 2014, Vol 346) utilized a combination of data from ESA’s Cluster spacecraft mission and the IMAGE spacecraft of NASA. The specific event in the Earth’s magnetosphere on September 15, 2005 was observed simultaneously by the spacecraft of both missions.

Illustrations of the Cluster II spacecraft in orbit and formation around the Earth and the NASA IMAGE spacecraft vehicle design. The two mission's observations were combined to correlate numerous auroral and magnetospheric events. Cluster II remains in operation as of December 2014 (14 yr lifespan). (Credit: ESA, NASA)
Illustrations of the Cluster II spacecraft in orbit and formation around the Earth and the NASA IMAGE spacecraft vehicle design. The two mission’s observations were combined to correlate numerous auroral and magnetospheric events. Cluster II remains in operation as of December 2014 (14 yr lifespan). (Credit: ESA, NASA)

Due to the complexity of the Sun-Earth relationship involving neutral and charged particles and electric and magnetic fields, space scientists have long attempted to make simultaneous measurements with multiple spacecraft. ISEE-1, 2 and 3 were one early attempt. Another was the Dynamics Explorer 1 & 2 spacecraft. DE-2 was in a low orbit while DE-1 was in an elongated orbit taking it deeper into the magnetosphere. At times, the pair would align on the same magnetic field lines. The field lines are like rails that guide the charged particles from far out in the magneto-tail to all the way down to the upper atmosphere – the ionosphere. Placing two or more spacecraft on the same field lines presented the means of making coordinated observations of the same event. Dr. Fear and colleagues analyzed data when ESA’s Cluster resided in the southern lobe of the magnetotail and NASA’s IMAGE (Imager for Magnetopause-to-Aurora Global Exploration) spacecraft resided above the south polar region of the Earth.

Cluster is a set of four spacecraft, still in operation after 14 years. Together with IMAGE, five craft were observing the event. Fear, et al utilized ESA spacecraft Cluster 1 (of four) and NASA’s IMAGE. On that fateful day, the IMF turned north. As described in Dr. Fear’s paper, on that day, the north and south lobes of the magnetosphere were closed. The magnetic field lines of the lobes were separated from the Solar wind and IMF due to what is called magnetic reconnection. The following diagram shows how complex Earth’s magnetosphere is; with regions such as the bow shock, magnetopause, cusps, magnetotail, particle belts and the lobes.

Illustration of the Earth's magnetosphere showing it complexity. The Theta Aurora are now confidently linked to magnetic reconnection events in the lobes of the magnetotail. (Credit: NASA)
Illustration of the Earth’s magnetosphere showing it complexity. The Theta Aurora are now confidently linked to magnetic reconnection events in the lobes of the magnetotail. (Credit: NASA)

The science paper explains that what was previously observed by only lower altitude spacecraft was captured by Cluster within the magnetotail lobes. The southerly lobe’s plasma – ionized particles – was very energetic. The measurements revealed that the southern lobe of the magnetotail was acting as a bottle and the particles were bouncing between two magnetic mirrors, that is, the lobes were close due to reconnection. The particles were highly energetic.

The presence of what is called a double loss cone signature in the electron energy distribution was a clear indicator that the particles were trapped and oscillating between mirror points. The consequences for the Earth’s ionosphere was that highly energetic particles flooded down the field lines from the lobes and impacted the upper atmosphere transferring their energy and causing the magnificent light show that we know as the Northern Lights (or Southern) in the form of a Theta Auroral Oval. This strong evidence supports the theory that Theta aurora are produced by energized particles from within closed field lines and not by energetic particles directly from the Solar Wind that find a path into the magnetosphere and reach the upper atmosphere of the Earth.

A video of an observed major geomagnetic storm (July 15, 2000) taken by the Far Ultraviolet Imaging System (FUV) on IMAGE. IMAGE operated from 2000 to December 2005 when communications were lost. (Credit: NASA/SWRI) [click to view the animated gif]
A video of an observed major geomagnetic storm (July 15, 2000, southward IMF) taken by the Far Ultraviolet Imaging System (FUV) on the spacecraft IMAGE. IMAGE operated from 2000 until December 2005 when communications were inexplicably lost. (Credit: NASA/SWRI) [click to view the animated gif]
Without the coordination of the observations and the collective analysis, the Theta aurora phenomenon would continue to be debated. The analysis by Dr. Fear, while not definitive, is strong proof that Theta aurora are generated from particles trapped within closed field lines.

The analysis of the Cluster mission data as well as that of many other missions takes years. Years after observations are made researchers can achieve new understanding through study of arduous details or sometimes by a ha-ha moment. Aurora represent the signature of the interaction of two magnetic fields and two populations of particles – the Sun’s field and energetic particles streaming at millions of miles per hour from its surface reaching the Earth’s magnetic field. The Earth’s field is transformed by the interaction and receives energetic particles that it bottles up and energizes further. Ultimately, the Earth’s magnetic field directs some of these particles to the topside of our atmosphere. For thousands and likely tens of thousands of years, humans have questioned what it all means. Now another piece of the puzzle has been laid down with a good degree of certainty; one that explains the Theta aurora.

Reference:

Direct observation of closed magnetic flux trapped in the high-latitude magnetosphere

Transpolar arc evolution and associated potential patterns

Transpolar aurora: time evolution, associated convection patterns, and a possible cause

Related articles at Universe Today:

Guide to Space –

Earth’s Magnetic Field,

Aurora Borealis

Posted on by Bob King

Soar with the Aurora in this Breathtaking Real-time Video

Scene from "Soaring". Credit: Ole Salomonsen

“Soaring” by Ole Salomonsen

We’ve posted many beautiful aurora photos and videos over the years here at Universe Today, but this one about stopped my heart. Titled “Soaring”, it was all shot in real time by Ole Salomonsen, a landscape photographer based in Tromsø, Norway. Salomonsen has been shooting spectacular stills and videos of the northern lights for years. While not the first aurora video done in real time, it’s probably the most successful, high definition effort to date. Ole used a Sony A7S, which he calls “the best low light camera ever”.

It was shot from late August to mid-November in and around the city of Tromsø, as well as on the island of Senja, Norway’s second largest island and a three-hour drive from the city. But what sets this video apart from many is that it shows the aurora unfolding live as if you’re standing right there. No time lapse.

Coronal aurora scene from "Soaring". Credit: Ole Salomonsen
Coronal aurora scene from “Soaring”. Credit: Ole Salomonsen

Having witnessed the northern lights many times over the years from my home in northern Minnesota, I can vouch for how close to reality this work truly is. There’s a little more color saturation than what the naked eye would pick up, but the aurora’s changing rhythms are beautifully captured. Ole also mixes in dramatic pan shots taken as if you were running to find a clearing to get the best view. Honestly, that blew me away.

“Although auroras mostly move slowly and majestic, they can also move really fast,” wrote Salomonsen. After seeing the slow undulations of curtains and rays early in the film, you’ll really appreciate the aurora’s other side – its dazzling speed.

Scene from "Soaring". Credit: Ole Salomonsen
The human perspective – another scene from “Soaring”. Credit: Ole Salomonsen

“The corona I captured and the lightning fast sequences at the end are some of the most amazing shows I have witnessed in my many years of hunting and filming the lights,” added Ole.

And now for the most amazing part. What you just watched is only a fraction of what Salomonsen has shot during the season. Expect more soon!

Posted on by Nancy Atkinson

Wow! Epic 4K Timelapse of Aurora Over Iceland and Greenland

Screenshot from 'Two Lands: Greenland and Iceland' by Joe Capra.

Holy Northern Lights, Batman! This new timelapse is just beautiful! Photographer Joe Capra traveled to Greenland and Iceland to shoot 10 nights of the arctic Aurora. Not only was the aurora absolutely stunning, but the landscape is equally beautiful. Joe said that all the footage was shot in super high resolution 4K Ultra HD, and you can even see the bright aurora reflected in small rivers and streams.

Here are some of the locations Joe shot the footage: Greenland locations include the Kangerlussuaq, Ilulissat, Ilimanaq, Ilulissat Ice Fjord, Russell Glacier, Greenland Icecap, and Disko Bay. Iceland locations include the South Coast, Snæfellsnes Peninsula, Kirkjufell, and Grundarfjörður.

Check out more of Joe’s work at his website Scientifantastic.

Two Lands – Greenland | Iceland from SCIENTIFANTASTIC on Vimeo.

Posted on by David Dickinson

Aurora on Venus Versus Solar Activity

Credit:

It’s a major mystery posed by our sister world.

Does the atmosphere of Venus possess upper atmospheric phenomena similar to the Earth, such as aurora or nightglow?

Now, a recent announcement out of the American Astronomical Society’s 46th annual meeting of the Division of Planetary Science being held this week in Tucson, Arizona has shed new light on the dilemma.

The discovery was announced on Wednesday, November 12th at the 46th AAS meeting and was made as a collaborative effort by researchers from New Mexico State University at Las Cruces, the Stanford Research Institute (SRI) International, the University of Colorado at Boulder, the University of Koln and University of Munich, Germany, the European Space and Technology Center in the Netherlands and the Institut de Recherche en Astrophysique et Planétologie, in France.

For the study, researchers observed Venus from December 2010 to July 2012 using the Astrophysical Research Consortium (ARC)Echelle Spectrograph and the ARC  3.5 metre telescope located at Apache Point near Sunspot, New Mexico.

Timing was crucial, as the Sun was coming off of a profound deep minimum through 2009 and just beginning to become active with the start of solar cycle #24. Observers were looking for activity along the 5577.3 angstrom wavelength known as the “oxygen green line.” Activity had not been seen at this wavelength on the nighttime side of Venus since 2004.

The altitude drop in the Venusian atmosphere measured in the study. Credit : Credit: DPS press release/C. Gray/New Mexico State University.

“These are intriguing results, suggesting that it is possible to have aurora on non-magnetic planets,” said Candace Gray, Astronomer and NASA Earth and Space Science Fellow at Las Cruces and lead researcher in the study.  “On Venus, this green line has been seen only intermittently.”

Earth is the oddball among the terrestrial planets in the inner solar system with its robust magnetic field. On Earth, aurorae occur when said field captures charged particles ejected from the Sun and funnels them in towards the poles. Events seen in the study tended to drop 140 to 120 kilometres in altitude in the Venusian atmosphere, highly suggestive of auroral activity seen in the ionosphere of Earth.

Researchers were fortunate during one of the recent runs at Apache Point that the Sun kicked off a coronal mass ejection that headed Venus’s way. During the July 2012 solar storm, the team detected one of the brightest green line emissions that had ever been detected by observers on Earth.

Credit: Wikimedia Commons image.
The 3.5 metre telescope at Apache Point, in this case, being used for lunar ranging experiments. Credit: M3long/Wikimedia Commons image.

This demonstrates that perhaps, a magnetic field is optional when it comes to auroral activity, at least in the case of the planet Venus. Located only 0.7 astronomical units (108.5 million kilometres) from the Sun, our tempestuous star actually wraps the planet with its very own magnetotail.

Researchers are also looking to compare their results with observations from the European Space Agency’s Venus Express orbiter which arrived at the planet on April 2006.

“Currently, we are using observations from VIRTIS on Venus Express to try and detect the green line,” Gray told Universe Today. “We had coordinated ground based observations with them this past February, and we detected the green line from the ground when they were observing the night side limb. Additionally, we are using the Electron Spectrometer and ASPERA-4 to observe how the electron energy and density changes in the atmosphere after coronal mass ejection impacts.”

This also raises the interesting possibility that NASA’s MAVEN spacecraft — which recently arrived in orbit around Mars — might just detect similar activity in the tenuous Martian atmosphere as well. Like Venus, the Red Planet also lacks a global magnetic field.

Could this glow be connected with spurious sightings of the “Ashen Light of Venus” that have cropped up over the centuries?

Of course, ashen light, also known as Earthshine on the dark limb of the Moon, is easily explained as sunlight reflected back from the Earth. Moonless Venus, however, should be ashen light free.

“The green line emission that we see is brightest on the limb (edge) of the planet,” Gray told Universe Today. “We’re sure that there is emission all along the nightside, but because of the optical depth, it appears much brighter on the limb of the planet. I think it would be too faint to detect with the naked eye.”

Nightglow has been a leading suspect for ashen light on the Venusian nightside, and a similar green line emission detection rivaling the 2012 event was made by Tom Slanger using the Keck I telescope 1999.

Other proposed suspects over the centuries for ashen light on Venus include lightning, volcanism, light pollution (!) from Venusian cities, or just plain old observer error.

Certainly, future observations are needed to cinch the solar activity connection.

“We will likely observe Venus again from Apache Point the next time Venus is visible to us in June 2015,” Gray told Universe Today. “We will continue looking at Venus Express observations until the craft dies in the atmosphere.”

Venus turns its night time back towards us during the 2012 transit of the Sun, as seen from NASA's Solar Dynamics Observatory (Credit: NASA/SDO).
Venus turns its night time back towards us during the 2012 transit of the Sun, as seen from NASA’s Solar Dynamics Observatory (Credit: NASA/SDO).

Venus can currently be seen crossing through the field of view of SOHO’s LASCO C3 camera. After spending most of 2014 in the dawn sky, Venus will emerge from behind the Sun low in the dusk to head towards greatest elongation in the evening sky on June 6th, 2015. And from there, Venus will once again slender towards a crescent, presenting its nightside towards Earth, and just perhaps, continuing to present a lingering mystery of modern astronomy.

Posted on by Nancy Atkinson

Incredible Fast-Moving Aurora Captured in Real Time by Thierry Legault

One image of the fast-moving aurora captured over Norway in October, 2014. Credit and copyright: Thierry Legualt.

Usually, videos that feature aurora are timelapse videos, in order to show the normally slow movements of the Northern and Southern Lights. But here are some incredibly fast-moving aurorae shown in real time, as seen by astrophotographer extraordinaire Thierry Legault. He was in Norway last week and said the fast-dancing, shimmering aurora were incredible.

“At moments they were so fast that 25 fps (frames per second) was not too much!” Legault said. “The second evening they were so bright that they appeared while the sky was still blue and I rushed to setup the tripod.”

See two videos below, one short version (8 minutes) and another longer 20-minute version. They are worth watching every minute!

He used Sony A7 video cameras, and said these movies show the true rhythm of the aurora, in addition with twinkling stars and trees moving in the wind.

“In the long version there are even several satellites slowly moving amongst the stars and 2 or 3 elusive shooting stars,” Legault told Universe Today. “Many constellations are visible, especially Cassiopeia with the double cluster, the Big Dipper, Cygnus, Lyra, Gemini.”

He added that the aurorae had an incredible variety of shapes and behaviors.

See more imagery on Legault’s website.

Posted on by Nancy Atkinson

Astro-Panarama: Aurora on the Farm

A 180° panorama of ant aurora display behind grain bins on a country road in Alberta, Canada. Credit and copyright: Alan Dyer/Amazing Sky Photography.

Since I grew up on a farm, I know how lovely the night sky can be when you’re out in the country. But this new image from Alan Dyer is just astounding!

This 180-degree panorama shows an aurora display behind grain bins on a country road in Alberta, Canada. “The aurora adds more color to a sky also filled with green airglow,” Alan wrote on Flickr, “while at the ends of the roads are yellow glows of light pollution, from Strathmore and Calgary at left, and Bassano at right. For a few minutes there was also the sharp edge at left to the aurora rays, present in 3 frames of the panorama, so it is not an artifact of the stitching. The Big Dipper is left of centre, low in the north.”

Just gorgeous. Plus, it reminds me of home…

You can click on the image above to see larger versions.
#TerrestrialTuesday

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.

Posted on by Bob King

How to Take Great Pictures of the Northern Lights

A group of amateur photographers set up on a beach on Lake Superior near Duluth to photograph the northern lights. To shoot the aurora you'll need a tripod and middle to high end digital camera. Pocket cameras work well in daylight and can be used to shoot bright northern lights, but the images will be noisy. Credit: Bob King

Everybody loves pictures of the northern lights! If you’ve never tried to shoot the aurora yourself but always wanted to, here are a few tips to get you started.

"T" stands for a terrific aurora seen last winter from near Duluth, Minn. US. Photo taken with a high-end digital camera (Canon Eos 1 Mark III) at ISO 800, 30-second exposure. Credit: Bob King
“T” stands for a terrific aurora seen last winter near Duluth, Minn. U.S. Photo taken with a high-end digital camera (Canon EOS 1-D Mark III) at ISO 800, 30-second exposure. Credit: Bob King

The strong G3 geomagnetic storm expected tonight should kick out a reasonably bright display, perfect for budding astrophotographers. Assuming the forecasters are correct, you’ll need a few things. A location with a nice open view to the north is a good start. The aurora has several different active zones. There are bright, greenish arcs, which loll about the northern horizon, parallel rays midway up in the northern sky and towering rays and diffuse aurora that can surge past the zenith. Often the aurora hovers low and remains covered by trees or buildings, so find a road or field with good exposure.

15-second time exposure of Vega rising taken with a typical digital pocket camera. Notice the grainy texture. Credit: Bob King
15-second time exposure of Vega rising taken with a typical digital pocket camera. Notice the grain or noise throughout. Credit: Bob King

Second, a tripod. You can do so much with this three-legged beast. No better astro tool in the universe. Even the brightest auroras will require a time exposure of at least 5 seconds. Since no human can be expected to hold a camera steady that long, a tripod is a necessity. After that, it comes down to a camera. Most “point-and-shoot” models have limited time exposure ability, often just 15 seconds. That may be long enough for brighter auroras, but to compensate, you’ll have to increase your camera’s sensitivity to light by increasing the “speed” or ISO. The higher you push the ISO, the grainier the images appear especially with smaller cameras. But you’ll be able to get an image, and that may be satisfaction enough.

I use a Canon EOS-1 Mark III camera to shoot day and night. While not the latest model, it does a nice job on auroras. The 16-35mm zoom wide-angle lens is my workhorse as the aurora often covers a substantial amount of sky. My usual routine is to monitor the sky. If I see aurora padding across the sky, I toss the my equipment in the car and drive out to one of several sites with a clear exposure to the north. Once the camera meets tripod, here’s what to do:

A bright, very active aurora. I used my zoom lens at 16mm at f/2.8 and a 15-second exposure at ISO 800.
A bright, active aurora. I used my zoom lens at 16mm at f/2.8 and about a 15-second exposure at ISO 800. Credit: Bob King

* Focus: Put the camera in manual mode and make sure my focus is set to infinity. Focusing is critical or the stars will look like blobs and the aurora green mush. There are a couple options. Use autofocus on a cloud or clouds in the daytime or the moon at night. Both are at “infinity” in the camera’s eye. Once focused at infinity, set the camera to manual and leave it there the rest of the evening to shoot the aurora. OR … note where the little infinity symbol (sideways 8) is on your lens barrel and mark it with a thin sharpie so you can return to it anytime. You can also use your camera in Live View mode, the default viewing option for most point-and-shoot cameras where you compose and frame live. Higher-end cameras use a viewfinder but have a Live View option in their menus. Once in Live View, manually focus on a bright star using the back of the camera. On higher-end cameras you can magnify the view by pressing on the “plus” sign. This allows for more precision focus.

* Aperture: Set the lens to its widest open setting, which for my camera is f/2.8. The lower the f-stop number, the more light allowed in and the shorter the exposure. Like having really big pupils! You want to expose the aurora in as short a time as possible because it moves. Longer exposures soften its appearance and blur exciting details like the crispness of the rays.

My friend Glenn takes a night sky shot silhouetted against the northern lights. Credit: Bob King
A friend takes a night sky shot silhouetted against the glow of the northern lights. Credit: Bob King

*  ISO speed: Set the ISO to 800 for brighter auroras or 1600 for fainter ones and set the time to 30-seconds. If the aurora is bright and moving quickly, I’ll decrease exposure times to 10-15 seconds. The current crop of high end cameras now have the capacity to shoot at ISOs of 25,000. While those speeds may not give the smoothest images, dialing back to ISO 3200 and 6400 will make for photos that look like they were shot at ISO 400 on older generation cameras. A bright aurora at ISO 3200 can be captured in 5 seconds or less.

* Framing: Compose the scene in the viewfinder or monitor. If you’re lucky or plan well, you can include something interesting in the foreground like a building, a picturesque tree or lake reflection.

* Press!: OK, ready? Now press the button. When the image pops up on the viewing screen, does the image seem faint, too bright or just right. Make exposure adjustments as needed. If you need to expose beyond the typical maximum of 30 seconds, you can hold the shutter button down manually or purchase a cable release to hold it down for you.

Great example of a well-composed photo with an interesting foreground choice. An intense aurora on September 12, 2014 in central Maine. Credit: Mike Taylor
Great example of a well-composed photo with an interesting foreground choice. This intense aurora was shot on September 12, 2014 in central Maine. Credit: Mike Taylor

It’s easy, right? Well then, why did it take me 400 words to explain it??? Of course the magic happens when you look at the monitor. You’ll see these fantastic colorful forms and ask yourself “did I do that?”

Have fun and good luck in your photography.

Posted on by Bob King

Will Aurora Strike Tonight? Here’s What to Expect

A bright arc and pink-topped rays stipple the northern sky and cross the Bowl of the Big Dipper last night around 11:30 p.m. CDT over Caribou Lake north of Duluth, Minn. Credit: Guy Sander

(Scroll down for latest update)

Auroras showed up as forecast last night beginning around nightfall and lasting until about 1 a.m. CDT this morning. Then the action stopped. At peak, the Kp index dinged the bell at “5” (minor geogmagnetic storm) for about 6 hours as the incoming shock from the arrival of the solar blast rattled Earth’s magnetosphere. It wasn’t a particularly bright aurora and had to compete with moonlight, so many of you may not have seen it. You needn’t worry. A much stronger G3 geomagnetic storm from the second Earth-directed coronal mass ejection (CME) remains in the forecast for tonight. 

 

Plot showing the Kp index of magnetic activity high in the Earth's magnetic domain called the magnetosphere. The two red bars show the Kp at '5' last night and early this morning (dotted line represents 0 UT or 7 p.m. CDT). Inset is the current detailed forecast in 3-hour increments. Credit: NOAA
Plot showing the Kp index of magnetic activity high in the Earth’s magnetic domain called the magnetosphere. The two red bars show the Kp at ‘5’ last night and early this morning (dotted line represents 0 UT or 7 p.m. CDT). Inset is the current detailed forecast in Universal Time (Greenwich Time) in 3-hour increments. Credit: NOAA

Activity should begin right at nightfall and peak between 10 p.m. and 1 a.m. Central Daylight Time. The best place to observe the show is from a location well away from city lights with a good view of the northern sky. Auroras are notoriously fickle, but if the NOAA space forecasting crew is on the money, flickering lights should be visible as far south as Illinois and Kansas. The storm also has the potential to heat and expand the outer limits of Earth’s atmosphere enough to cause additional drag on low-Earth-orbiting (LEO) satellites. High-frequency radio transmissions like shortwave radio may be reduced to static particularly on paths crossing through the polar regions.

Earth’s magnetic bubble, generated by motions within its iron-nickel core and shaped by the solar wind, is called the magnetosphere. It extends some 40,000 miles forward of the planet and more than 3.9 million miles in the tailward direction. Credit: NASA
Earth’s magnetic bubble, generated by motions within its iron-nickel core and shaped by the solar wind, is called the magnetosphere. It extends some 40,000 miles forward of the planet and more than 3.9 million miles in the tailward direction. Most of the time it sheds particle blasts from the sun called coronal mass ejections, but occasionally one makes it past our defenses and we get an auroral treat. Credit: NASA

If you study the inset box in the illustration above, you can see that from 21-00UT (4 -7 p.m. Central time) the index jumps quickly form “3” to “6” as the blast from that second, stronger X-class flare (September 10) slams into our magnetosphere. Assuming the magnetic field it carries points southward, it should link into our planet’s northward-pointing field and wreak beautiful havoc. A G2 storm continues through 10 p.m. and then elevates to Kp 7 or G3 storm between 10 p.m. and 1 a.m. before subsiding slightly in the wee hours before dawn. The Kp index measures how disturbed Earth’s magnetic field is on a 9-point scale and is compiled every 3 hours by a network of magnetic observatories on the planet.

A lovely rayed arc reflected in Caribou Lake north of Duluth, Minn. on September 11, 2014. Credit: Guy Sander
A lovely rayed arc reflected in Caribou Lake north of Duluth, Minn. on September 11, 2014. Tonight the moon rises around 9:30 p.m. The lower in the sky it is, the brighter the aurora will appear. Hopefully tonight’s lights will outdo what the moon can dish out. Credit: Guy Sander

All the numbers are lined up. Now, will the weather and solar wind cooperate?  Stop back this evening as I’ll be updating with news as the storm happens. For tips on taking pictures of the aurora, please see this related story  “How  to Take Great Pictures of the Northern Lights”.

The auroral oval around 2:30 p.m. CDT this afternoon September 12 shows a southward expansion into the Scandinavian countries and Russia and Iceland. Where the sky is dark, auroras are typically seen anywhere under or along the edge of the oval. Click for current map. Credit: NOAA
The auroral oval at 11:15 p.m. CDT tonight September 12 shows a temporary pullback into northern Canada. Where the sky is dark, auroras are typically seen anywhere under or along the edge of the oval. Click for current map. Credit: NOAA

* UPDATE 8:15 a.m. Saturday September 13: Well, well, well. Yes, the effects of the solar blast did arrive and we did experience a G3 storm, only the best part happened before nightfall had settled over the U.S. and southern Canada. The peak was also fairly brief. All those arriving protons and electrons connected for a time with Earth’s magnetic field but then disconnected, leaving us with a weak storm for much of the rest of the night. More activity is expected tonight, but the forecast calls for a lesser G1 level geomagnetic storm.

* UPDATE 11 p.m. CDT: After a big surge late this afternoon and early evening, activity has temporarily dropped off. The ACE plot has “gone north” (see below). Though we’re in a lull, the latest NOAA forecast still calls for strong storms overnight.

Definite aurora seen through breaks in the clouds low in the northern sky here in Duluth, Minn. After a big surge late this afternoon and during early evening, activity's temporarily dropped off. The ACE plot has "gone north".
Definite aurora seen through breaks in the clouds low in the northern sky here in Duluth, Minn. After a big surge late this afternoon and during early evening, activity’s temporarily dropped off. The ACE plot has “gone north”.

* UPDATE 9 p.m. CDT: Aurora a bright greenish glow low in the northern sky from Duluth, Minn.

* UPDATE 7:45 p.m. CDT September 12: Wow! Kp=7 (G3 storm) at the moment. Auroras should be visible now over the far eastern seaboard of Canada including New Brunswick and the Gaspe Peninsula. I suspect that skywatchers in Maine and upstate New York should be seeing something as well. Still dusk here in the Midwest.