Category Archives: Photos

Winter Solstice 2015 Solar Storm Recap

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Northern Lights Now – On December 20th and 21st of 2015 the third largest geomagnetic storm of solar cycle 24 treated aurora hunters to 30 hours of dancing lights. The long duration of the storm gave nighttime photographers in North America two opportunities to see the northern lights through gaps in the clouds. Aurora reports on Twitter filled the NLN feed with images first from Wisconsin, then Alberta, Alaska, New Zealand, Northern Europe, Austria, Germany, England, Ireland, Iceland and then the North America again. Here is a chart of the official NOAA/SWPC recorded KP values from Boulder during the storm:

Boulder recorded 30 hours of G1-G2 storming during the winter solstice storm. of 2015
Boulder recorded 30 hours of G1-G2 storming during the winter solstice storm. of 2015

This solar storm started from two events on the Sun’s surface. The first was a long duration C6.69 flare at nearly dead center in the Earth strike zone. The second was a filament eruption to the south and east of the first eruption. Both events produced CMEs. Read more about the pair of eruptions NLN’s initial blog post on this storm.

Giants Causeway in Northern Ireland by Roy Smith Photo:

The CMEs from these two storms arrived later than initially predicted. Initial predictions were that the leading edge of the CME would reach Earth early in the day on December 19. The CME’s initial interplanetary shock was detected in ACE satellite data around 1520 GMT. Those 15 hours were time that many nighttime photographers wished they were sleeping instead!

Once they arrived, the two storms hit in sequence, not quite merging. As the storms played out, both had strongly negative Bz. Negative Bz is an aurora hunter’s dream. Once the field shifts south, a good show is sure to come – but we never know Bz until Earth is in the CME cloud. Space Weather scientists are still anticipate a long time before Bz can be accurately predicted in advance of a CME arrival. For now, forecasters assume arriving CMEs plasma clouds have a roughly 50/50 chance of being oriented with a Bz south.

In the Winter Solstice Storm of 2015, once the Bz shifted south, it stayed strongly south for 32 hours from 02:30GUTC on the 20th through 1030UTC on the 21st. During that time, the Bz deflection remained around -16 to -18 nT. Interestingly, after the initial shock, solar wind speeds stayed relatively low at below 450km/s for the duration of the storm. Had solar wind speeds been stronger, it’s possible that G3 level storming might have occurred. The slow wind speeds probably increased the duration of the storm (if the CME was moving faster, it would have completed it’s pass by Earth more quickly).

With a special shoutout to @VirtualAstro who helped surface some of these, here are some of our favorite images from this worldwide display of northern lights:

Swirls of green glow behind snow covered pine trees in Alaska by David W. Shaw

Green and yellow arches in the sky behind a church in Alberta by Célestine Aerden:

A string of pearls in the sky, technically called Auroral Beads, @Inukphysiker called this “lightsabors in the sky”

Another star wars reference came from Notanee Bourassa with this light-sabor aurora selfie

Team Tanner in Alberta often captures wonderful northern lights images, this anelic set was from Theresa (Tree) Tanner:

Finally, a stunning backdrop of purples and greens behind a solitary KW photography in Upstate New York:

Happy Hunting!

December 2015 Aurora Among Best of Solar Cycle 24

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Northern Lights Now – A solar storm resulting from a pair of CMEs arrived at Earth on December 19, 2015 and induced 30 hours of G1-G2 aurora activity. It proved to be one of the strongest geomagnetic storms of solar cycle 24. Aurora hunters around the world were able to capture stunning photographs of green, red, pink, and purple swirling through the sky. NLN will be writing a complete recap post, but here is a teaser of amazing tweets that has been in the NLN feed over the last two days.

Rob Write Photos – based in Maine from the evening of Dec 20 just after sunset:

Peter Caltner share this, showing the Aurora as far south as the Austrian Alps:

In Ireland, reports came in from Waterford. Here’s a picture from Waterford of the aurora with purple mixed in by Rónán McLaughlin:

Jake Stehli caputured this set of pictures in Wisconsin on the first night of the storm, just as it was really kicking up.

And one of our favorites of this storm so far by KW photography:

Happy Hunting

NLN Aurora Brief – November 7, 2015

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Aurora Brief Volume 3, Number 5 of 7
Other Briefs: Previous BriefNext Brief

On the Sun

New Active region 2449 is rotating into view on the eastern limb. It is still to early to tell for sure what magnetic classification is should have yet. It will be more clear for tomorrow’s Aurora Brief. This region produced a a C4.48 flare, the largest flare of the period. The flare did not produce and Earth-directed CME. All other regions remained the same, or decreased in magnetic complexity.

On Earth

At the end of the period, a CME shock was recorded hitting the ACE satellite. The shock registered on ground based magnetometers about 45 minutes later. KP readings for the end of the period were as high as 4.67. Here are two aurora pics that came in on Twitter just as the aurora was getting going.

So far this solar storm’s Bz component has again been North pointed. So once again, storming levels will be limited. This could shift to South at any time, so don’t give up hope yet!

The continues to be a G1 watch in effect for both November 7 and November 8 as the CME from the M3.7 flare is expected to arrive. It is unclear at this point whether the shock the arrived just now was that expected CME, or if there will be another shock as main CME arrives. For now, aurora hunters can keep their fingers crossed that the second storm will arrive later today and that it will have a more favorable Bz component.

Remember to keep a eye on the current KP.

Happy Hunting!