Tag Archives: alberta

Storm Recap – G1 Storming Gives Canadians a Show On May 10-11 2019

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Northern Lights Now – Geomagnetic conditions reached G1 storm level over the weekend. Aurora hunters across Canada were treated to a show. Even with low solar wind speeds that just touched 400 km/s, a long duration of south oriented Bz combined with high plasma density was enough to activate the magnetosphere. The recorded 3-hour observations from the storm show one period of Kp=5 in the first period of May 11 followed by sever periods of KP=4

G1 storm levels reached between 12:00am  and 3:00am on Saturday May 11.
G1 storm levels reached between 12:00am and 3:00am on Saturday May 11.

There was not a storm watch posted in advance of this activity, but the SWPC daily forecast discussion mentioned the possibility. The forecaster’s note from May 9 read “The anticipated arrival of the 6 May CME is expected to result in unsettled to active conditions, with a chance for an isolated period of G1 (Minor) geomagnetic storm levels, later on 11 May.” NLN was posting on the Twitter feed that there was a chance for activity in advance of the storm, but the activity exceeded our expectations.

As the storm arrived, it became clear that Earth was going to be in the core of the arriving CME and that it was oriented favorably for Northern Lights. Proton density was high for hours in advance of the CME arrival shock. Once it arrived, Bz dipped south and stayed oriented south for 5-6 hours. Wind speed did not increase above 400km/s in the first part of the core of the storm, as so geomagnetic activity remained muted. But the long duration south oriented Bz primed the magnetosphere for the second phase of the storm.

Long duration of southward Bz Orientation
Long duration of southward Bz Orientation

As the second phase arrived, Bz dropped deeply south and stayed consistent. This drove the KP to storm levels and it coincided with night across much of Western Canada.

Happy Hunting!

G3 Aurora Recorded Sept 27/28 – More G1 Ahead

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Northern Lights Now – The late September geomagnetic activity resulting from a large coronal hole has exceeded initial expectations reaching G3 storm levels and helping aurora hunters world-wide capture staggering views. Solar wind speeds have been between 650 and 750 km/s for just over 24 hours now. Periods of high density and negative Bz, and quickly fluctuating Bz during that time pushed KP values above 6.67 for several hours.

Recorded KP values from SWPC in Boulder indicate 7 synoptic periods for G1+, 2 with G3 stroming
Recorded KP values from SWPC in Boulder indicate 7 synoptic periods for G1+, 2 with G3 stroming

The timing worked well for aurora hunters from Northern Europe across Northern North America. Clouds disrupted viewing in the UK and New England, but many locations saw vivid displays of Green, Red and Purple overnight.

Wendy T shared this great set of 4 images

Casey Grimley captured some pinks and the coveted fishbone aurora in Ogden Valley

And Jeff Wallace shared some spectacular full sky Gree swirling aurora

Looking ahead – it seems likely that at least G1 storming will continue through at least the next 12 hours or so. SWPC has extended their G1 storm watch an additional 24 hours through Sept 29.

Looking ahead - G1 watch is extended through Sept 29
Looking ahead – G1 watch is extended through Sept 29

We love that you share your photos with us on Twitter and on Facebook. Thank you for helping with out mission to help as many people see the aurora borealis as possible.

Happy Hunting

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!