Tag Archives: active region

Early November 2021 Complex Aurora Live Blog

Northern Lights Now – A complex set of flares and CMEs has set up a period of potential aurora activity on Nov 3rd through 5th. The official forecast is calling for a period of G1 storming late on the third for 6-9 hours, then another period late on the 4th potentially into the 5th. As such, the Aurora liveblog is being activated

NLN Live Blog Update – Thursday, November 4, 02:30 UTC (07:00 EST 11/4)
Live blog time: 19 Hours 00 mins

Wow!

Aurora hunters are being treated to a show with G3 aurora in high latitudes. Every time there is a solar storm expected, there is uncertainty in how it will be oriented when it arrives. This storm arrived with nearly perfect orientation for aurora sightings. As of now, there has been six hours of strong (-10nT) south oriented Bz, 15+ hours of solar wind speeds over 700 km/s, 1+ hours of solar wind speeds over 800 km/s, nearly 15 hours of Bt over 15 nT. With data like that, it isn’t surprising Earth has been experiencing G3 and possibly even G4 conditions.

Strong Bz south for almost the entire 3-hour lookback window
Strong Bz south for almost the entire 3-hour lookback window

The ovation model, which estimates where it’s likely to have active aurora, is showing a wide swath of red across almost all of Canada, Alaska, and Russia. In the southern hemisphere, Australia and New Zealand have been treated to a show. This storm is a worldwide event.

Lots of red on the ovation model - November 4, 2021
Lots of red on the ovation model – November 4, 2021

NLN Live Blog Update – Thursday, November 4, 02:30 UTC (22:30 EST 11/3)
Live blog time: 5 Hours 30 mins

Bz has been rolling in and out of south orientation, solar wind speeds have been holding above 750 km/s and the BT has remained strong. This has brought strong sub-storms during the Bz south periods. KP reached 7 (the highest it has been so far this solar cycle) and there have been aurora reports coming in from Maine, Vermont, Eastern Canada, Scotland and more.

KP reaches 7 during the early November storm on Nov 4, 2021
KP reaches 7 during the early November storm on Nov 4, 2021

At the moment, it appears Bz may be rotating back to the south. If this continues aurora hunters could see another round of aurora over the next 2-3 hours. There is also the possibility that we could see another shock arrival in the next 6 hours or so. If this happens we could have an abrupt end to the show, or it could intensify. Most likely, given the strength of the solar wind we are in the main portion of the storm and have less than 12 hours left of this storm.

NLN Live Blog Update – Wednesday, November 3, 22:10 UTC (18:10 EST 11/3)
Live blog time: 1 Hours 10 mins

The Aurora pictures have started!

NLN Live Blog Update – Wednesday, November 3, 21:20 UTC (17:20 EST 11/3)
Live blog time: 0 Hours 20 mins

After a momentary outage, Solar wind data is back online. With winds over 700 km/s and Bz strongly south, there is likely already G1 storming occuring

Momentary outage, but solar winds are still strong
Momentary outage, but solar winds are still strong

NLN Live Blog Update – Wednesday, November 3, 21:00 UTC (17:00 EST 11/3)
Live blog time: 0 Hours 0 mins

The first sign of the CMEs arrival hit DSCOVR at about 19:20 UTC, with a stronger impact around 20:00. Initial readings are showing a strong south Bz component and high solar wind speeds above 650 km/s. This is already an indication that this storm could yield better aurora production that the previous storm from Halloween weekend. This data means it is likely that we will reach G1 storming within about 90 minutes.

First signs of ICME impact around 19:20 UTC Nov 3, 2021
First signs of ICME impact around 19:20 UTC Nov 3, 2021

About an hour after the storm starting impacting, a glitch and set of errors has made DSCOVR blind to the solar wind. Aurora hunters will need to fall back on ACE as a source for data until DSCOVR comes back on line.

Solar Cycle 25 Underway, First Activity Reported

Northern Light Now – The long absence of large solar flare activity may come to an end soon as solar cycle 25 active regions start to appear. The last C-class flare occurred on May 15, 2019 from active region 12741. In the 7 months since, there have been only 19 active regions numbered as the Sun has been in the depths of the cyclic solar minimum. For aurora hunters, the only source of activity has been from an occasional filament eruption and High Speed Streams originating at Coronal Holes. However, over the last several months there are indications that the next solar cycle is picking up and activity will return over the next year. Aurora hunters should start looking forward to the next season.

The Solar Cycle lasts about 11 years. During each cycle, activity increases for about five and a half years. The monthly count of active regions and sunspots visible on the Sun increases until Solar maximum. At maximum, the Sun’s polarity flips and activity slowly tapers back into solar minimum over the remaining five and a half years in the cycle. Currently, the Sun is in the least active part of this cycle and as a result there have been fewer and weaker aurora displays over the last year.

Chart Shows Active regions by month with solar minimum highlighted
Chart Shows Active regions by month with solar minimum highlighted

Solar Cycle 24 (SC24) started in January of 2008 and peaked in July of 2013 and is ending now. At peak, there were nearly 300 active regions numbered in 2013. There were only 22 new active regions numbered in 2019. There is normally an overlap between the end of one solar cycle and the beginning of the next. Of those 22 active regions numbered in 2019, only 17 actually belong to SC24, the other 5 are part of Solar Cycle 25.

When Will Solar Activity Increase?

By the start of the next northern hemisphere aurora season! Aurora hunters can expect the 6 to 9 months ahead to continue to have very low solar activity. During the minimum between SC23 and SC24 there were about 30 months with fewer than seven active regions numbered. In the current minimum, the last month with more than seven active regions identified was September of 2017 – or 27 months ago. This is an arbitrary threshold, but can prove useful when making an estimate. Projecting out and assuming the same length of solar minimum, May or June should be the first month with 7 newly numbered active regions of Solar Cycle 25.

While there won’t be much activity from CMEs originating at active regions, it will certainly be possible that there will be activity from coronal holes. Attentive space weather fans will have noticed over the last couple years that Coronal Holes are the primary driver behind aurora activity during solar minimum. It is possible there will also be activity from filament eruptions (link to what happened today). Overall, the frequency of storms should be about the same over the last 6 months as it will be over the next 6 months – that is to say, not much.

The frequency and magnetic complexity of SC25 regions will continue to increase. With each new region, the likelihood of the next C-class flare increases. Seasoned aurora hunters know that long duration C, M and X class flares are one of the keys to a good northern lights display. Of course, a more complex AR could develop at any time and produce an strong flare, it is just far less likely during solar minimum. So keep watching the data and keep watching the active regions.

Happy Hunting

Active Region 2712 Enters Earth Strike Zone

Northern Lights Now – Active Region 2712 produced a beautiful B class flare On May 24 as it rotated into view in the northern hemisphere of the Sun. The region held together and grown slightly and has now produced a C-class flare that measured C2.77. Today the region has started to develop some mixed magnetic fields and shows potential to produce more C-class flares. It is now in the Earth strike zone.

AR2712 produced this flare on the East limb as it was rotating into view.
AR2712 produced this flare on the East limb as it was rotating into view.

Keep an eye on this region over the next several days. If it generates an eruptive flare and a CME it could impact Earth’s space weather later this week. Here’s a time lapse of the region show in SDO’s HMI colorized magnetogram.

Happy Hunting