Tag Archives: flare

Filaments and a Flare in Early November

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Northern Lights Now – There have been several notable eruptions on the Sun since November 4th. As of now, models are not indicating G1 storming, but with the combination of events, and models predicting KP=4, it is not out of the question that there may be some G1 storming between 11/8 and 11/9.

Early on the 4th a filament erupted from the SW portion of the disk. There is a clear CME lift off, but it appears to be headed mostly to the South and West of the Earth-Sun line. Here is an animatedGIF showing about 4 hours in AIA 304 with showing the filament erupting

Filament erupts off in the SW quadrant of the Solar disk early on Nov 4 UTC
Filament erupts off in the SW quadrant of the Solar disk early on Nov 4 UTC

About 6 hours later, a small B2.2 flare happened around an unnumbered region in the NW quadrant. Just after this low level eruption, a wave is visible traveling southward through the corona. Dimming was also seen in automated CME detection during this flare. Often, dimming is indicative of a launching CME, but there was no clear sign of a CME on LASCO. If this flare did launch a CME towards Earth, it will be a stealth CME. This flare was optical only and did not register on NLN’s Solar Flare Browsing page. In this video, the first half shows the full disk, the second half zooms in on the actual flare.

Finally, a pair of filaments erupted early on the 5th. The first, bigger one launched from the NW quadrant of the Solar disk from a location just north of the area of the B2.2 flare. This filament also showed what looked to be a launching CME on AIA 304, however most of the material looks to be traveling North and West. The other filament erupted on the East of the disk at nearly the same time and is much smaller. They are both visible in this AIA 193 imagery, the second is just barely visible.

Filament erupts off the north west limb early on Nov 5. Shown in AIA 193
Filament erupts off the north west limb early on Nov 5. Shown in AIA 193

Happy Hunting!

One Year Anniversary of St. Paddy’s Day Aurora 2016

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Northern Lights Now – St. Patrick’s Day, March 17, falls on a Thursday this year providing the perfect Throwback Thursday to last year, when the strongest Aurora storm of the current solar cycle arrived at Earth. Aurora hunters, including Dan Russell and this author, the Burlington VT based founders of NLN, were treated to hours on end of wondrous dancing lights. Dan and I captured these purple pillars with a camera on a tripod setup on the frozen ice of Lake Champlain:

Purple Aurora Pillars
Aurora glow and purple pillars visible in NLN’s photograph from St. Patrick’s Day Aurora Storm 2015

The storm that produced this aurora was only predicted to be 12-18 hours of G1 storming prompted by a filament eruption followed by a long duration C9 solar flare. Both events launched CMEs towards Earth, and as they arrived it became clear they were oriented just right for a long duration and very strong show. The plasma cloud from the filament and the CME from the flare arrived almost in unison. This sent the Bz strongly south by as much as 23nT. Bz remained south for over 24 hours, and the solar wind speeds increased to over 600km/s. By the time the storm subsided, there were two full days of G1+ activity including periods of G4:

Two full days of G1 storming reflected in the KP 3-hour chart from Boulder
Two full days of G1 storming reflected in the KP 3-hour chart from Boulder

This was not an easy storm to photograph in Vermont. The forecast for the evening did not look promising from the start. It was supposed to be cloudy all day and through the night on March 17 and it was cold! It was 24 degrees, and the wind was howling at 20 with gusts to 35mph (no exaggeration!) The northern lights activity was predicted to die down as the sun set over Lake Champlain, so at best there might only be a short window. As the afternoon waned, two factors came together nicely – first the storm was clearly stronger than expected, second there were hints in the very short term forecast that there could be a window where the clouds broke apart between sunset and about 9:30.

Cloudcover for St Paddy's day storm 2015 shows hints of clear skies for  Lake Champlain
Cloudcover for St Paddy’s day storm 2015 shows hints of clear skies for Lake Champlain

The batteries were charged, so we set up the cameras. This was a particularly cold March in Northern New England after a particularly cold winter. Lake Champlain and Mallott’s bay still had a thick layer of ice. We set the camera up pointed North and watched as a break in the clouds moved from West to East. When the sky cleared aurora were visible to the naked eye and we captured the image at the top of this post. There was a 45 minute window before the clouds rolled back in. Every Aurora hunter knows that feeling when the night is over because the clouds roll in. Dan and I went inside to warm up and to start processing images. While we sat inside, a squall came through dumping over an inch of snow.

At midnight, just as it was time to turn in, we looked out the window and it was crystal clear and there was red aurora in the sky to the North visible to the naked eye. We set the cameras up and let the intervalometer snap 5 second exposures on our Fujifilm X-T1 and Rokinon 12mm f/2.0 cameras. Did I mention it was cold? Now that it had snowed, the north wind was creating a “ground blizzard” as it picked up the freshly fallen snow and blew it across the lake at 20 mph. Here’s what Dan and I looked like, huddled behind a raised block of ice acting as a wind barrier, as we waited for the second round of photos at 1:00am.

Charles and Dan Shelter from the wind while time lapse camera snaps photos
Charles and Dan Shelter from the wind while time lapse camera snaps photos

It was worth it! At the end we had this time lapse that shows both the 8:30-9:30pm and 12:30-1:30am periods where the sky was clear. You can see the ice on the lake, and watch the clouds roll in during the first section, then in the second see one of the most amazing displays of Red, Green and Purple we’ve been lucky enough to experience.

Happy Hunting!

Valentine’s Day G1 Aurora Watch Posted By SWPC

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Northern Lights Now – The Space Weather Prediction Center (SWCP) has posted a G1 geomagnetic storm watch indicating probable KP>5 for February 14th and 15th 2016. This means aurora borealis may be visible in mid latitudes. The timing indicates that Europe and North America will be best positioned for a show Valentine’s Day Evening. As always with storm watches like this, the actual storming period could arrive up to 6 hours before or after the predicted arrival. Now is the time to start monitoring developments in space weather and cloudcover forecasts to know if the northern lights will be visible to you and planning your night our aurora hunting.

Update: Feb 13: NLN is now posting live updates for this storm.

As of the time the watch was posted, Earth is expected to see KP levels at 5 or above from 21:00GMT on 2/14 through 06:00GMT on 2/15 (4:00m-1:00am EST). There may be up to 12 hours past the arrival of the storm where KP may still be in the KP=4+ range. The forecast may be updated as more data comes in, so keep an eye on the NLN 3-day AuroraCast page for updates over the next couple days. As of this post, here is the current AuroraCast:

NLN 3-day Aurora cast for days 2 and 3 shows KP=5 possible on February 14 and 15, 2016
NLN 3-day Aurora cast for days 2 and 3 shows KP=5 possible on February 14 and 15, 2016

This storm is caused by a Coronal Mass Ejection (CME) that erupted from the surface of the Sun during a C8.92 flare on February 11th. You can see that eruption in the northwest (upper left) quadrant of the solar disk in this timelapse captured from the Solar Dynamic Observatory Satellite. SDO is a camera trained on the Sun that takes thousands of high resolution images per day in multiple different wavelengths. As the Flare erupts over the course of almost 90 minutes, you can see a dark area moving up and away from the eruption location. This dark area, several times the size of Earth, is the CME. It appears as dimming because the ejected plasma is cooler than the Sun and located between the Sun and the camera on the SDO sattelite.

C8.92 Solar flare launches from Active Region 2497 on 2/11. The CME may produce Aurora on 2/14 and 2/15

Normally, CME’s take 2-3 days to arrive at Earth after an eruption. The eruption is moving much slower and will take 3-4 days to arrive. That could mean that it will arrive with lower solar wind speed, which would dampen chances for a great show. But it also means that as it arrives, it may put on a longer show. Stay tuned for updates!

Happy Hunting