Tag Archives: sweden

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

2017-18 Aurora season starts with a G1 storm watch for Aug 31 and Sept 1st

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Northern Lights Now – The fall aurora season kicks off around the end of August when the nights in the Nordic countries (Sweden, Finland, Norway, Iceland and Denmark) start to get long enough and dark enough to see the northern lights. This year, the season should start off with a bang as a G1 storm is predicted that should bring a nice show.

Northern Lights Now Twitter follower Mia Stålnacke captured these pictures in Sweden earlier this week as aurora season gets under way.

Earth will come under the influence of a coronal hole, a corotating interaction region (CIR) and a solar storm over the next several days. There is a chance conditions may reach G2 on September 1st as the edge of a solar storm delivers a glancing blow.

On August 31st the high speed winds generated by the coronal hole shown below will start to push on Earth’s magnetosphere. The CH, which is the dark area on the image below, covers much of the northern hemisphere and crosses into the southern hemisphere. That means it is highly likely the winds will pick up at Earth about 3 days after the region was pointed towards Earth on the center of the disk. At about the same time, the CIR will also arrive. Current models indicate the solar wind speeds could reach between 550 and 600 km/s.

Coronal Hole Pointed Towards Earth on August 29
Coronal Hole Pointed Towards Earth on August 29

Later, on Sept 1 a small solar storm that was released during an eruption near active region 2672. Watch that eruption in this video. The eruption happened on the very western edge of the Earth stike zone and is not large. Most of the plasma emitted will miss earth to the west, but in the WSA-Enlil model below, see that the flank of the cloud may brush by Earth. Earth’s magnetosphere is likely to be activated as a result of 36 hours of high speed wind. That activation should accentuate any impact from the solar storm.

WSA Enlil model shows the solar storm and the coronal hole high speed stream (CH HSS)
WSA Enlil model shows the solar storm and the coronal hole high speed stream (CH HSS)

With this space weather setup, there is a good chance that at least one of the features will produce G1 storming (KP=5 or higher) in the next three days. If the solar storm is oriented just right, and is moving slightly faster than modeled and arrives in closer proximity to the high speed solar wind, KP values may reach G2 storm levels. Below is the official forecast from SWPC as displayed by the NLN auroraCast clock. Orange shows periods when G1 storming is expected:

SWPC is predicting days two and three with KP=4 possible in every three hour period
SWPC is predicting days two and three with KP=4 possible in every three hour period

Aurora hunters should be watching the data over the next three days and have their cameras ready.

Happy Hunting

Surprise G1 Aurora Storm on August 23/24 2016

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Northern Lights Now – The high speed wind stream from a coronal hole that was pointed towards Earth on August 21 is arriving with a stronger than expected impact. As a result KP values are reflecting an ongoing G1 level storm. The storm has allowed aurora hunters to see the lights in Denmark and Sweden and in the US in Maine. The initial forecasts only called for a period of enhanced solar wind speeds and a max KP value of 4. This is the coronal hole that is currently impacting Earth as it looked on August 21:

Aug 21 coronal hole produces Aurora and G1 storming on Aug 23rd and 24th
Aug 21 coronal hole produces Aurora and G1 storming on Aug 23rd and 24th

The high speed wind arrived earlier than expected, and stronger than expected. As an added bonus for our readers, it arrived with a period of several hours of southern oriented Bz. When the Bz component of the magnetic fields have negative readings, it means aurora are more likely. As this storm was building, it arrived with a period of over 4 hours where the Bz was negative from about 16:00-20:00 UTC. At points it was strongly negative with readings of -10Bz. This is the image of NLN’s accumulated aurora power chart from the peak of the first wave of the storm:

DISOVR accumulate Aurora power Graph from the peak of the first wave of the storm
DISOVR accumulate Aurora power Graph from the peak of the first wave of the storm

There are a couple interesting things to point out in that graph:

  • At the time of the snapshot the total magnetic field (Bt) had been strong for over 12 hours, and very strong in the last hour.
  • Wind speeds had really only just started picking up in the last 2 hours.
  • The real kicker was that Bz had been negative for over 2 hours and was as strong at -10nT (very strong) for 5 minutes.

It is rare that a coronal hole triggers all 4 of these metrics at the same time on this chart. When they are all there, it’s a good sign for aurora hunters.

Here are some of the shots that we saw come in on Twitter:

Some of the first Images of this storm came from Denmark by @ADphotography24:

Another from Sweden by Göran Strand (Also the first wave of this storm):

From Rob Write (@RobWrightImages) on the Southern Maine Coast (in the second wave of this storm):

As of 3:20 UTC August 24 at the time of this writing, the storm has subsided a little. It looks like there could be anywhere from 3-6 more hours of enhanced solar wind speeds, and at any point the Bz could dip back south. If it does, Aurora hunters could be in for more of a treat. Keep an eye on the solar wind data.

Also, there is another coronal hole rotating towards Earth that has a history of producing good aurora. This could impact Earth on Aug 30th and 31st…. stay tuned!

Happy Hunting