Weekly Space Hangout – November 15, 2013

Host: Fraser Cain

Guests: Jason Major & David Dickinson

Jason Major on:
Awesome New Image from Cassini
Mars Was Earthlike Millions of Years Ago

David Dickinson on:
Comet R1 LoveJoy at its brightest
Leonid Meteors this weekend
MAVEN Launches on Monday

Fraser Cain on:
Reminder re: Comet ISON photo contest
Cory Schmitz’ Aurora Photos
Curiosity’s Journey to Mount Sharpe
The Moon Has Bigger Craters on the Near Side
Super Typhoon Haiyan from Space
Two Workers Killed in Plesetsk

We record the Weekly Space Hangout every Friday at 12:00 pm Pacific / 3:00 pm Eastern. You can watch us live on Google+, Universe Today, or the Universe Today YouTube page.

Astrophotos: Aurora Reflections from Iceland

Aurora Borealis, beach reflection, and Orion, in Iceland on the beach Jökulsarlon. Image was taken on November 7, 2013. Credit and copyright Cory Schmitz

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?

Aurora Borealis,  shot with a Canon 5DmkII and Canon 14mm f/2.8 LII prime lens at Jökulsarlon beach in Iceland on November 12, 2013. Credit and copyright: Cory Schmitz.
Aurora Borealis, shot with a Canon 5DmkII and Canon 14mm f/2.8 LII prime lens at Jökulsarlon beach in Iceland on November 12, 2013. Credit and copyright: Cory Schmitz.

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.

Recent Sun Activity Spawns Stunning Aurorae

The auroral view while driving up Atigun Pass, North Slope Borough County, Alaska, US on November 1, 2013. Credit and copyright: Jason Ahrns.

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.

Aurora seen over northern Norway on October 22, 2013. Credit and copyright: Frank Olsen.
Aurora seen over northern Norway on October 22, 2013. Credit and copyright: Frank Olsen.

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.

Aurora over Sukakpak, Yukon-Koyukuk Census Area County, Alaska, US, November 1, 2013. Credit and copyright: Jason Ahrns.
Aurora over Sukakpak, Yukon-Koyukuk Census Area County, Alaska, US, November 1, 2013. Credit and copyright: Jason Ahrns.
A stunning green aurora almost covers the sky, but peeking through are the  Pleiades and the Andromeda Galaxy. Credit and copyright: Jason Ahrns.
A stunning green aurora almost covers the sky, but peeking through are the Pleiades and the Andromeda Galaxy. Credit and copyright: Jason Ahrns.

Planet Aurora Astro-Bubble

A unique panoramic image from of the aurora seen over Norway on October 14. Credit and copyright: Göran Strand.

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.”

This isn’t the first time we’ve seen photographers create their own little worlds from panoramic images (see here and here). Here’s a tutorial on how to do this.

Timelapse: Aurora Over Lake Michigan

A still photo taken of the aurora over Lake Michigan. Credit and copyright: Shawn Malone/Lake Superior Photo.

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.

RADIANCE from LakeSuperiorPhoto on Vimeo.

Technicolor Auroras? A Reality Check

Beautiful red and green aurora the night of Oct. 1-2, 2013. See below for how it appeared to the eye. Details: 20mm lens, f/2.8, ISO 1600 and 25-second exposure. Credit: Bob King

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.

Shocked? I took the photo above and using Photoshop adjusted color and brightness to match the naked eye view. Credit: Bob King
Surprised? I took the photo above and using Photoshop adjusted color and brightness to match the naked eye view. Notice the green tinge in the bright arc at bottom. The rays were colorless. Credit: Bob King


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.

A massive wall of bright purple and green rays from July 20, 2012. Details: 16mm at f/2.8, ISO 800 and 20 second exposure. Credit: Bob King
A massive wall of bright purple and green rays from July 20, 2012. Details: 16mm at f/2.8, ISO 800 and 20 second exposure. Credit: Bob King

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.

Image adjusted to better represent the visual view. Credit: Bob King
Image adjusted to better represent the visual view. Most auroras are between 60 and 150 miles high, but occasionally reach to 400 miles. Credit: Bob King

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.

Excitation of oxygen and nitrogen atoms and molecules by incoming solar electrons causes them to give off specific colors shown here. Credit: NCAR
Incoming auroral electrons excite oxygen and nitrogen atoms and molecules which then shoot out photons of light at specific wavelengths when they return to their ground states. Oxygen beams light at 557.7 (green) and 603 (red) nanometers. Credit: NCAR

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.

The layers of our atmosphere showing the altitude of the most common auroras. Credit: Wikimedia Commons
The layers of our atmosphere showing the altitude of the most common auroras. Credit: Wikimedia Commons

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.

A striking coronal aurora in Feb. 1999 photographed on film. The red in this aurora was obvious to the naked eye but appeared more like the Photoshopped version at right. Credit: Bob King
A striking coronal aurora in Feb. 1999 photographed on film. The red in this aurora was obvious to the naked eye but appeared more like the Photoshopped version at right. Credit: Bob King

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.

 

Awesome Photo: Aurora, Airglow, City Lights and Shining Stars

Photo taken by ESA astronaut Luca Parmitano on Sept. 5, 2013 (ESA/NASA)

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.

See this and more photos taken by Luca on the Volare Flickr page here.

Image credit: ESA/NASA

Overnight Aurora Sets Sky On Fire, More Possible Tonight

At around 10 p.m. last night, the northern sky was alive with colorful auroral patches and arcs. Details: 15mm lens at f/2.8, ISO 800 and 25 second exposure. Credit: Bob King

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.

An erupting filament and sharp, southward turn in the interplanetary magnetic field (IMF) was responsible for last night's northern lights show. This image was taken with the Solar and Heliospheric Observatory sun-blocking coronagraph in progress on Sept. 30. Credit: NASA/ESA
An erupting filament and sharp, southward dip in the interplanetary magnetic field (IMF) was responsible for last night’s northern lights show. This image was taken with the Solar and Heliospheric Observatory’s sun-blocking coronagraph on Sept. 30. Credit: NASA/ESA

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.

A classic quiet start to Tuesday night's northern lights - a low green arc below the Big Dipper topped by a very faint red border. Credit: Bob King
A classic quiet start to Tuesday night’s northern lights – a low green arc below the Big Dipper topped by a very faint red border. Credit: Bob King

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.

A single patch of aurora glows beneath the Pleiades star cluster at center. Beautiful red rays as seen in the time exposure were only faintly visible with the naked eye. Credit: Bob King
A single patch of aurora glows beneath the Pleiades star cluster at center. Beautiful red rays as seen in the time exposure were only faintly visible with the naked eye. Credit: Bob King

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.

A thick wall of green aurora surges upward in the northern sky headed for the zenith. Credit: Bob King
Looks a little scary. A thick wall of green aurora surges upward in the northern sky headed for the zenith. Credit: Bob King

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.

A large comet-like auroral form topped with red rays took up residence in the southeastern sky in Cetus around 10:30 p.m. last night. Credit: Bob King
A large comet-like auroral form accented with red rays took up residence in the southeastern sky in Cetus from about 10:15 until 11 p.m. last night. around 10:30 p.m. Credit: Bob King

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.

Opposite Cetus in the Aquila Milky Way, a huge ghostly patch resembling breath on a mirror lingered for some 20 minutes before fading away. Credit: Bob King
Opposite Cetus in the Aquila Milky Way, a huge ghostly patch resembling breath on a mirror lingered for some 20 minutes before fading away. Credit: Bob King
This comet-like wisp next to Alpha Andromeda east of the Square of Pegasus appeared to flutter in the wind as it constantly dimmed, brightened and shape-shifted. Credit: Bob King
This comet-like wisp next to Alpha Andromeda east of the Square of Pegasus appeared to flutter in the wind as it constantly dimmed, brightened and shape-shifted. Click photo to learn more about when to expect the next auroral display. Credit: Bob King
Finally - a mighty show of rays around 3 a.m. this morning. What you don't see in the photo  are the rhythmic pulsations fluttering through the entire display, a phenomenon known as "flaming". Credit: Bob King
Finally – a mighty show of rays around 3 a.m. this morning. What you don’t see in the photo are the rhythmic pulsations fluttering through the entire display, a phenomenon known as “flaming”. Credit: Bob King

 

Magnetic and auroral activity indicators shot up to high levels last night and this morning. Left image from the POES satellite shows the extent of the auroral oval shortly after midnight CDT. At right, the Kp index shot up to 6 - a G2 or moderate geomagnetic storm - by the early morning. Click to see the current oval. Credit: NOAA
Magnetic and auroral activity indicators shot up to high levels last night and this morning. Left image from the POES satellite shows the extent of the auroral oval shortly after midnight CDT. At right, the Kp index shot up to 6 – a G2 or moderate geomagnetic storm – by the early morning. Click to see the current oval. Credit: NOAA

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:

Aurora Borealis, 'The Northern Lights, as seen near Dayton, Ohio on October 2, 2013. Credit and copyright: John Chumack/Galactic Images.
Aurora Borealis, ‘The Northern Lights, as seen near Dayton, Ohio on October 2, 2013. Credit and copyright: John Chumack/Galactic Images.

And Alan Dyer in Canada got this amazing “fiery” shot:

A red and green aurora, from southern Alberta, Canada on Oct 1, 2013. Credit and copyright: Alan Dyer/Amazing Sky Photography.
A red and green aurora, from southern Alberta, Canada on Oct 1, 2013. Credit and copyright: Alan Dyer/Amazing Sky Photography.

This timelapse from Arthur, Ontario was shot on Oct. 2 as well:

Lovely Astrophotos: Aurora Among the Clouds

Aurorae dance across the sky and among the clouds over Norway on September 28, 2013. Credit and copyright: Frank Olsen.

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.

Aurora among the clouds at twilight in Norway on September 18, 2013.  Credit and copyright: Frank Olsen.
Aurora among the clouds at twilight in Norway on September 18, 2013. Credit and copyright: Frank Olsen.

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.

Your Guide To When, Where and How To See The Aurora Borealis

A beautiful display of the aurora borealis on June 6 this year. The line of light is the International Space Station; an airplane is off to the left. Credit: Bob King

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.

Continue reading “Your Guide To When, Where and How To See The Aurora Borealis”