March opens with auroras popping

Rays reach across the northern sky during last night's display of the northern lights. Credit: Bob King

Rays reach across the northern sky during last night’s display of the northern lights. Pardon the quality – it’s a hand-held exposure wedged against my deck railing. Credit: Bob King

Today begins a brand new month and maybe a break from February’s long cold spell. It might also be the start of a new round of auroral activity. Last night a nice G1 geomagnetic storm brought us active streamers and rays across the northern sky. This despite moonlight and, at least for northern Minnesota, pesky clouds, too.

NOAA space weather forecasters are calling for a second round of G1 or minor auroral storms this evening between about 6 p.m. and midnight (CST). Solar disturbances at Earth are rated on a 1 to 5 scale. G1 events usually bring auroras down to the northern tier of U.S. states from Maine to Washington. Other effects include minor fluctuations in power grids and possible impacts on computer hardware in orbiting satellites.

A good way to keep tabs on whether or not the aurora is out is to check the K or Kp index, a measure of magnetic activity in Earth's high atmosphere. The index is updated every 3 hours. The dotted line is 6 p.m. CST (0 hours UT). A Kp index of 5 often means auroras are out in the northern U.S. Credit: NOAA

A good way to keep tabs on the aurora is to check the K or Kp index, a measure of magnetic activity in Earth’s upper atmosphere. The index is updated every 3 hours. The dotted vertical line marks 6 p.m. CST (0 hours UT). A Kp index of 5 indicates a G1 storm is in progress; Kp=6 equals a moderate storm and Kp=9 an extreme event. Click to see the live index. Credit: NOAA with annotations by the author

With a G5 or extreme storm, even Floridians should expect auroras. Satellite electronics and poorly protected power grids can suffer damage, shortwave radio propagation cuts out and induced electric charges in oil pipelines by rapidly changing electrical currents in Earth’s ionosphere can lead to corrosion.

Let’s hope tonight’s predicted aurora brings a similar parade of active rays in the northern sky. Naturally, the moon will be a problem, but if your sky is otherwise dark, you might see a fair show.

This Sun this morning March 1 photographed in UV light by SDO. Credit: NASA

This Sun this morning March 1 photographed in UV light by SDO. Credit: NASA

Like last night, tonight’s source of auroral inspiration is that large, dark “hole” seen in images taken in ultraviolet light by NASA’s orbiting Solar Dynamics Observatory (SDO). Coronal holes are regions small and large on the Sun, where the solar wind of electrons and protons flows freely away from our star at high speeds. All the fluffy yellow plumage in the photo above are magnetic fields that form a sort of canopy over much of the Sun, constraining the flow of particles into space. Holes are free-for-all zones.

Video showing the Sun rotating with a coronal hole

Last night, the magnetic field embedded within the stream pointed south upon its arrival, canceling Earth’s northward-pointing magnetic field and opening a channel into our protective magnetic domain called the magnetosphere. Once “in the building”, the particles shot down into the upper atmosphere and struck atoms and molecules there to create the aurora we saw.

Forecast for midnight tonight Feb. 28-March 1 showing how the auroral oval has expanded southward across southern Canada and the northern U.S. Credit: NOAA

Forecast from last night Feb. 28-March 1 showing how the auroral oval expanded southward across southern Canada and the northern U.S. Credit: NOAA

Besides the K-index described above, another excellent tool to check on aurora is the Aurora 30-minute forecast site. Here you’ll see a near-live view of the auroral oval, the halo of permanent auroras found centered on Earth’s geomagnetic poles. When a storm ensues, the oval (or ovals – there’s a southern one, too) expands southward from its polar lair into southern Canada and the U.S.

The forecast here is for clear tonight, so I’ll be out watching. Check back for an update then.  Good luck!

Surprise auroral storm / Comet Lovejoy update / Jupiter,moon tight tonight

Aurora and the Full Wolf Moon photographed on January 5th from Abisko National Park in Sweden. A surprise auroral storm early this morning produced auroras visible across Canada and the northern U.S. even in moonlight. Click to see more aurora photos. Credit: Oliver Wright /

No one suspected it was coming, but this morning from about 3 a.m. till dawn (Central time) Earth’s magnetic bubble went bananas and busted out with auroras. At peak, the Kp index hit “7” for a G3 or strong geomagnetic storm. If only we’d known.

The auroral oval around 3:30 a.m. (CST) January 7th. Credit: NOAA

The storm appears to have been sparked by a large coronal mass ejection that may have occurred on January 3rd. The blast was originally thought to have happened on the far side of the Sun.  As the rogue solar winds passed Earth, its embedded magnetic field happened to “point south”. South-pointing magnetism find easy linkage with Earth’s north-pointing field, opening a portal for solar electrons and protons to stream in and incite polar auroral displays.

A G3 event expands the ever-present auroral oval far enough south that even folks in Illinois and other mid-western states as far south as Illinois will see the northern lights. While the activity has dropped off this afternoon, minor storming is still expected early this evening. Look to the north before moonrise for signs of a bright greenish arc.

Comet Lovejoy through a 200mm telephoto lens yesterday January 6th around 7 p.m. (CST). The comet was fainly visible with the naked eye. You can just see the tail pointing to the left of the blue-green coma. Details: 2.5 seconds, ISO 16,000. Credit: Bob King

Earlier last night before moonrise, we had clear skies here in Duluth, Minn., presenting us with a brief but nice showing of Comet Q2 Lovejoy in the constellation Eridanus. With only about 20 minutes of dark sky and the comet relatively low in the southeast it was still faintly visible with the naked eye. My 10×50 binoculars offered up the best view of the comet’s big, condensed coma; it was surprisingly easy to see about 1.5° (three full moon diameters) of faint tail streaking off to the northeast.

Watch for the waning gibbous moon to rise in conjunction with the planet Jupiter this evening. This map shows the sky facing east around 9 p.m. local time. Source: Stellarium

The moon rises later tonight leaving us even more dark sky for comet viewing. It also joins the company of the planet Jupiter this evening. Yes! The two orbs will be in conjunction tonight and really grab your eye when you face east for a view.

Click play and see the aurora sizzle and blaze in real time

Singe frame from the new video “Soaring”, one of the best real-time aurora videos. It was taken with a Sony A7S camera. This image shows a vivid coronal aurora near the zenith. Credit: Ole Solomonsen

We’ve often shared pictures and videos of the northern lights here, but wait till you see the latest video from Norwegian landscape photographer Ole Salmonsen. Salomonsen has been shooting still images and time-lapse video of the aurora for years. This week he posted a brand new movie of the aurora shot from late August through mid-November in real-time. You heard correctly – no sped-up, compressed time.This is the aurora moment-to-moment just the way you’d see it live.

“Soaring” by Ole Salomonsen

There are lots of nice touches in the video including scenes of Tromsø, Norway (where Ole is based), a woman staring into the sky and several truly amazing panned sequences that look to me like they were shot with a drone. What’s your opinion?

Although Ole’s work isn’t the first real-time aurora movie, this might be the best effort to date. The slowness of the initial sequences makes a striking contrast with later views of the coronal aurora unfolding at lightning speed and helps us to appreciate the complex rhythms that pulse through active displays.

I love it and hope you will too. For more on how the film was done, check out Ole’s site. Salomonsen tells me this work is just a small sample of what’s to come. Stay tuned!

Cloudy? Snowy? That won’t stop you from seeing THIS aurora

Aurora flyover in high-def video from the International Space Station

Wish it had been clear at dawn this morning. Some of us would have seen a very nice aurora. As predicted, Earth’s magnetic bubble got slammed by a package of high-speed solar wind overnight that fired up the northern lights. The impact continues to reverberate with more activity expected tonight.

No matter the weather or circumstance, I think you’ll enjoy this high-definition video taken from the International Space Station. The curls, rolls and flashing purple flames are, well, incredible. And there’s nothing quite like looking down on the aurora from an altitude of 250 miles (402 km). As the camera pans, you’ll also see the delicate green film of airglow, which is distinct from the northern lights – airglow surrounds the entire planet like a membrane around a cell.

Green, streaky airglow seen from the ground on July 22, 2014. Its faint light is half the reason you can always see around on even the darkest nights. The other light is provided by the stars. Credit: Bob King

Ultraviolet light from the daytime sun ionizes or knocks electrons off of oxygen and nitrogen atoms and molecules; at night the electrons recombine with their host atoms, releasing energy as light of different colors including green, red, yellow and blue.  The brightest emission, the one responsible for creating the airglow so often seen in space station nighttime images and videos, stems from excited oxygen atoms beaming emerald green light.

Forget about the clouds and take a ride with the astronauts where it’s forever clear.

Aurora alert tonight through Monday night Nov. 9-10

Aurora smolders beneath the Big Dipper tonight November 9th around 7 p.m. Credit: Bob King

Around 7 p.m. this evening, just before moonrise, a smoky green glow fired up beneath the Big Dipper low in the northern sky. The Moon rose and clouds soon followed, but we might be in for a couple nights of northern lights.

Cirrostratus clouds at moonrise this evening refracted moonlight into a pretty halo. Caught in the semi-circle is the Hyades star cluster (lower right). The Pleiades are at upper right. Credit: Bob King

A coronal mass ejection that launched from the Sun on November 7th will arrive overnight and could produce minor to moderate (G1-G2) geomagnetic storms now through midnight Monday night. The strongest activity is expected between 3-9 a.m. (CST) tomorrow morning.

A blast of high-speed electrons and protons from the Sun on November 7 looks like it may affect Earth overnight and into Monday. Credit: NASA/ESA

Tonight’s little taste will hopefully be a sign of more to come.

Auroras in the north tonight Oct. 14-15

Aurora low in the northern sky around 10:30 p.m. CDT this evening October 14, 2014. Credit: Bob King

Earlier this evening, a glancing blow from a solar blast that left the sun on October 10th jiggled Earth’s magnetic domain to produce a modest display of northern lights. Forecasters originally expected the coronal mass ejection (CME) to miss Earth. My astronomy class and I noticed a low arc in the north as early as 8:30 p.m. A half hour later, the arc broke apart into a beautiful set of evenly-spaced rays across the northern sky.

These slowly faded back to a quiet glow as if the aurora decided to take a nap and then re-brightened about 9:30. Right now at 11 p.m. the display has returned to a quiet arc about 5 degrees above the northern horizon directly below the Big Dipper. Something about it reminds me of a pale green feather boa.

The Kp index, a measure of how magnetically disturbed the upper atmosphere is, hit 5 this afternoon and evening, the mark of a minor geomagnetic storm. Auroras are usually seen across the northern border states when Kp=5. Credit: NOAA

NOAA space weather shows a G1 minor geomagnetic storm underway since the afternoon. Activity may be dropping off now, but it’s hard to say for sure, so keep a lookout for auroras tonight if you live in the northern states and southern Canada. Besides aftereffects of the solar blast, a chance for more auroras will continue the next couple nights due to “solar sector boundary crossings”. These are changes in the direction of the magnetic field within the solar plasma (electron and proton mix) that continually streams from the sun called the solar wind.

Coronal holes spark auroras Sept. 26-27 — more possible next 2 nights

The aurora around 1 a.m. CDT this morning. Curious forms twisted away in the northern sky in the Big Dipper. Details: 20mm lens, f/2.8, ISO 1600, 20-second exposure. Credit: Bob King

I apologize for not sending an alert earlier, but I was away from the computer and out under the sky tonight. Streams of solar wind from openings in the sun’s magnetic canopy called coronal holes kicked up auroras overnight for the northern states and Canada.

At 9:15 p.m. Friday night the aurora laid low in the northern sky. The arc is the curved border of the auroral oval that’s centered on Earth’s geomagnetic pole. Credit: Bob King

The display began and remained a very low arc from end of twilight until around 11 p.m. CDT when it slowly widened and brightened. The Kp index reached “4” at that time, not quite a G1 geomagnetic storm but certainly pushing the threshold. Then at 12:20 the arc became brighter and more distinct and split into an exquisite set of short, parallel rays like keys on a piano. Faint rays reached halfway to the zenith as patches of aurora flashed on and off below.

Nice long rays stretch over the forest near Duluth, Minnesota U.S. early this Saturday morning September 27, 2014. Credit: Bob King

While modest, the display was active with a steady supply of rays and pulsating patches, but it never expanded beyond the northern half of the northern sky. Coronal hole effects will linger the next two nights, so be on alert for auroras to appear again.

Check out the aurora! It’s on tonight Sept. 23-24

A fine aurora with many small rays spread across the northern sky around 10 p.m. CDT this evening September 23, 2014. Credit: Bob King

If the sky is clear and you live in the northern U.S. the northern lights are visible right now at 10-10:30 p.m. CDT. Not a huge display, but there’s a broad greenish arc/glow across the northern sky streaked with rays that reach up to the North Star. Very pretty.

A few bright rays below the Bowl and Handle of the Big Dipper at 10:15 p.m. Credit: Bob King

No telling how long it might last, but it’s been out at least since 9:30. No storms, not even minor ones, were in the forecast, but there you have it anyway. The Kp index is currently at “4” just below minor storm level and the direction of the magnetic field bundled with the solar wind has been tipped south (a good direction for linking up with Earth’s field) for about the past 7 hours. Let’s hope it sticks around!

* Update Weds. September 24 – We’re right on the edge tonight with a chance for a minor display of aurora according to the most recent forecast.

Extent of the auroral oval around 10:30 p.m. CDT shows expansion to the south. Notice the view line brushes the northern states. Click to see current oval. Credit: NOAA

What happened to the aurora? / New forecast for tonight Sept. 13-14

Observers in Maine were treated to a very nice aurora early last night September 12th. Mike Taylor saw this “intense aurora” light up above the unused railroad tracks along Unity Pond at 8:38 p.m. Click to see more of Mike’s work. Credit: Mike Taylor

Feeling disappointed in the aurora last night? The storm happened as forecast only it petered out just about the time the sky was getting dark across much of North America. Observers in Maine caught a good show early, and the lights even put in an appearance here in northern Minnesota, albeit low in the north from behind clouds.

The Kp index, an indicator of magnetic disturbances in Earth’s magnetosphere, shot up to “7” last night before dropping off to low activity, where it’s remained all day so far today. Credit: NOAA

NOAA space weather forecasters call for minor G1 storm tonight September 13 from about 10 pm to 4 a.m. Central Daylight Time tomorrow.

Minor usually means auroras in the bottom half of the northern sky for skywatchers living in the U.S.-Canada borderland region. You may choose to ignore the forecast and go to bed. I understand. You’re feeling a little burned. Those who feel like soldiering on, remain alert for possible auroras.

ACE orbits ahead of Earth toward the sun and can measure the clouds of plasma belted out by the sun about an hour before they arrive at Earth. Credit: NASA

It’s hard to blame NOAA. Predicting the magnetic inclination of a cloud of solar plasma at a distance is fraught with uncertainty. We get a little help from the Advanced Composition Explorer (ACE) which orbits at the L1 libration point, one of five places near Earth where the sun’s and Earth’s gravity are in balance, allowing a satellite placed there to remain relatively stationary. ACE pivots about some 932,000 miles (1.5 million km) from Earth and 92 million miles (148.5 million km) from the sun.

The probe detects the direction, strength and magnetic field particulars of incoming blasts of particles from the sun and provides advance warning of about one hour of dangerous storms. Storms that affect power grids, satellites and of course paint the sky in northern lights. It also measures the magnetic properties of the cloud and relays that data in real time for us to see in the ACE plots.

ACE plot of magnetic field direction or Bz from last night. You can see how the storm dissipated once the magnetic direction of the cloud changed from south (during the storm) to north (above the white horizontal line). Credit: NASA

Yesterday’s big puff of electrons and protons came packaged in a magnetic field that linked into Earth’s  – at first. But later in the evening, the cloud’s magnetic field changed from south to north and was effectively cut off from connecting with our planet’s magnetic bubble. Earth gave it the cold shoulder, and you and I lost some sleep.

After tonight, calmer conditions are expected for a couple days. After that, it’s anyone’s guess. I’ll be watching tonight and report back.

Showtime! Aurora makes first appearance – updated

A diffuse double is seen low in the northern sky at 9:30 p.m. CDT this evening September 11, 2014. The Big Dipper is off to the left. Credit: Bob King

(Scroll down for the latest update)

Just came in from a check on the northern lights and they’re out. Just a quiet start, but I can see a classic green arc low in the northern sky. Once my eyes were dark adapted, faint rays streaked the sky above the arc. No doubt they would have stood out more boldly were it not for the rising gibbous moon off to the east. Stay tuned for more updates during the night.

Faint rays streak either side of this photo taken at 9:35 p.m. Moonlight lowered the contrast but they were dimly visible with the naked eye. Credit: Bob King

Here are some links for you to check out to help you plan through the night:

The approximate extent of the auroral oval forecast for 10:30 p.m. CDT from Ovation. Credit: NOAA

* Ovation oval – shows the approximate extent of the auroral oval that looks like a cap centered on Earth’s geomagnetic pole. During storms, the oval extends south into the northern U.S. and farther.

* Kp index – indicator of magnetic activity high overhead and updated every three hours. A Kp index of “5” means the onset of a minor storm; a Kp of “6”, a moderate storm.

* NOAA space weather forecast

* Advanced Composition Explorer (ACE) satellite plots – The magnetic field direction of the arriving wind from the sun. The topmost graph, plotting Bz, is your friend. When it drops into the negative zone that’s good! A prolonged stay at -10 or lower increases the chance of seeing the aurora.

* UPDATE 8:15 a.m. Saturday Sept. 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 geomagnetic storm.

* UPDATE 10:30 p.m. : Although the aurora has died back, I just got the NOAA forecast update which still calls for a strong storm overnight. Crossing my fingers it happens.

Graph of Bz from the ACE spacecraft shows the past 24 hours of solar wind direction changes. Far right is 11 p.m. CDT Credit: NOAA

* UPDATE 9:30 p.m. : 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”. Will keep tabs and report back.

UPDATE Friday 7:30 p.m September 12: Wow! Kp=7 (G3 storm). Auroras should be visible now over the far eastern seaboard of Canada including New Brunswick and the Gaspe Peninsula. If I were a betting man, folks in Maine should see at least a low, glowing arc in the northern sky. Still dusk here in Duluth.

UPDATE Friday 3 p.m.: The Kp index is now at “5” or minor storm. If you live in the Scandinavian countries or Iceland, you’re getting a very good show right now.

* UPDATE Friday 9 a.m. September 12: Auroras did appear as forecast overnight beginning at nightfall and continuing through about 1 a.m. this morning. Then the action stopped. The Kp index reached “5” during that time leading to a G1 or minor geomagnetic storm. It wasn’t a particularly bright aurora, remained low in the northern sky and had to compete with moonlight, so many of you may not have seen it.

The stronger G3 geomagnetic storm from the second and more Earth-directed solar blast is still forecast for tonight. This should bring a much better display and should begin right at nightfall. Peak is expected between 10 p.m. and 1 a.m. Central Daylight Time.

My forecast is good, so I’ll be updating during the night. Good luck and clear skies!