Solar Section

February 21, 2021

Brief Summary of CR 2239

By Kim Hay
ALPO Solar Assistant Coordinator

Carrington Rotation #2239 (CR2239) started on December 25, 2020 at 22:30 (2020-12-25.9375; 2020.98819; Julian Date 2459209.43874) and ended on January 22, 2021 at 06:35.

The rotation continued with AR2794 & AR2795 taking the show. Even though they were beginning to decay by December 31^st, the groups still exhibited stable magnetic fields but failed to generate much activity in the flaring aspect. With the start of the new year solar activity declined, leading to a period of 12 days without any sunspot or group activity. On January 8^th SOHO recorded the Sun ejecting a large filament into space past Jupiter, “one of the biggest in years” according to the SpaceWeather.com website.

Things picked up on January 16^th with the arrival of group AR2796 in the Southern Hemisphere. It was joined the next day by another new group coming over the limb from the far side, earning its numbered designation as AR2797 on the 18th. January 21^st brought us AR2798 which continued its trek across the Sun with AR2797. At the tail end of the cycle groups AR2797 and AR2798 were crackling with C class flares.

Cycle CR2239 seemed to have fewer sunspot groups, closing out with a total of five active regions (AR2794-2798). Interestingly, all of them were located in the Sun’s southern hemisphere.

Data taken from the Sunspot Index and Long-term Solar Observations (SILSO) website

Thanks to the observers listed below who contributed 168 images and sketches to the ALPO Solar Image Gallery. Their work documenting CR2239 included observations in white light, H-alpha, and Calcium-K. We invite all interested Solar observers to join us on the ALPO Solar groups.io list where recent observation and news can be found. Details on how to subscribe can be found here.

Paul Andrew	Frank Melillo
Anthony Broxton	John O’Neal
Vlamir da Silva Junior	Theo Ramakers
Howard Eskildsen	Randy Tatum
Guilherme Grassmann	David Teske
Monty Leventhal	Geert Vandenbulcke

January 31, 2021

Ramp Up of Solar Activity Cycle 25

By Theo Ramakers

I was asked if it was true that it seemed that Cycle 25 activity ramped up faster than previous rotations. In order to try to shed some light into this, I am providing two graphs. It is noted here that each graph, while created by me, is based on data provided in the daily GEOalert notifications from NOAA’s Spaceweather Prediction Center (SWPC). Each graph shows the value of the sum of all daily active region areas for a Rotation since January 1, 2008 (Blue lines, mostly in the middle, with their scale on the left). Also shown is the number of spotless days. (red lines at the side with the scale on the right). The difference between the two graphs is that one of them shows the number of consecutive spotless days at the end of this spotless period (Streak).

The second graph below shows the number of spotless days by ROTATION at the last day of the rotation The number of these days reported by the size of the bars in this graph, don’t have to be consecutive, but the reported value is shown for an equal time period for all (one rotation). The Minimum for Cycle 23/24 (Beginning of Cycle 24) was in December of 2008. The Minimum for Cycle 24/25 (Beginning of Cycle 25) was during December of 2019, giving a cycle duration of 11 years. It is clearly seen that the blue lines (indicating Solar Activity) don’t start showing in 2009, one year following the minimum , but this cannot be said for 2020, a year after the next minimum. We surely see noticeable activity during the end of 2020. In addition, the Total Active Region Areas by Rotation show a higher value now than during the beginning of the previous solar minimum. In fact the Total Active Region Area by Rotation did not exceed 5000 millionths until August 9, 2010, or 20 months after the previous minimum. For the current Cycle, November 27, 2020 marks the first time where the 5000 millionths barrier was broken, and by well over 1000 millionths, which is only 11 months. So to summarize the results so far, Cycle 25 seems to gain in activity much faster than Cycle 24 did. We are eager to learn if this fast ramp up will continue.

January 16, 2021

Brief Summary of CR 2238

By Kim Hay
ALPO Solar Assistant Coordinator

CR2238 started on 2020-11-28 at 14:44 UT (Julian Date 2459182.11500 or Year 2020.91339) and ended some 27 days later on 2020-12-25 at 22:30 UT. This cycle saw a total of 13 Active Region (AR) sunspot groups AR2783 through AR2795.

Carrington Sunspot Data for CR2238
Data from SILSO

Carrington Rotation 2238 continued with high activity from AR2783 and AR2785-86 which originated with the prior rotation. By November 29^th a new group in the Northern Hemisphere, AR2787, showed up. This was the only Northern Hemisphere group for the CR2238 cycle. It has been noted by Solar physicists that the two hemispheres are not always in sync. Images from the Solar Dynamics Observatory (SDO) on December 4^th demonstrated this imbalance, especially in the H-alpha light. It could take up to two years for the Northern Hemisphere to catch up, but this is just part of a normal Sunspot Cycle.

Also on November 29^th, the far side of the Sun produced the largest Solar flare seen in three years with an M4.4 flare, producing a shortwave radio blackout over the Antarctic. The group responsible for the outburst, AR2790, rotated into view on December 2^nd. At this point in the cycle AR2786 was showing light bridges and decay.

There were several flares throughout CR2238 ranging from A to G1 activity. The flare from AR2790 produced much media attention for possible aurora activity but it fizzled out, producing aurora only in the higher latitudes.

A new sunspot group on December 12^th, AR2792, emerged in the Southern Hemisphere exhibiting Bxo/Beta and producing a C4 class flare.

December 4th, 2020 had a total Solar Eclipse in South America. One of our observers, Guilherme Grassmann from Brazil, obtained an image of the eclipse in Calcium light.

AR2793 emerged on December 15^th, but a few days later during December 19-20 the Sun was void of sunspots. That was short lived, however, as new sunspot activity arrived on December 21^stin the form of AR2794, followed by AR2795 showing up on Christmas Day. This closed out the Carrington Rotation with stable sunspots and groups with no chance of aurora activity.

Thanks to the contributors who forwarded their sketches and images for inclusion in the ALPO Solar Image Gallery for AR2238:

Paul Andrew
Anthony Broxton
Vlamir da Silva Junior
Howard Eskildsen
Guilherme Grassmann
Monty Leventhal
Frank Melillo
John O’Neal
Theo Ramakers
Randy Tatum
David Teske
Geert Vandenbulcke

We invite you to join the A.L.P.O. Solar email list to keep
current with all the Solar activity and the efforts of your fellow observers.

December 17, 2020

Brief Summary of CR 2237

By Kim Hay
ALPO Solar Assistant Coordinator

CR2237 started on November 1, 2020 at 07:21 UT and ended on November 28 at 14:45 UT.

November started off very low in sunspot numbers with AR2780 and AR2781 producing a C class flare on November 8th. This in turn triggered an auroral display in the upper atmosphere for the Northern hemisphere. By the 12th AR2782 produced a C class flare, and the Stereo A satellite was monitoring two UV hotspots on the backside of the sun which were getting close to appearing

On November 18th new Sunspot AR2783 appeared. On November 20th, this spot produced two long B flares in UV. There was a Northern group AR2784 that showed up briefly on November 22nd. Then the next day saw AR2785 (S23E66, Hsx/alpha) and AR2786 (S16E74 Hsx/alpha), and AR2783 (S22W00, Cso/beta) develop trailer spots with B-class activity. AR2784 (N23E08 Bxo/beta) was stable and quiet. A C class flare was reported from AR2785. The Wilson Effect was seen on images by the SDO and Pete Lawrence (UK). It was also captured in images by ALPO observers Theo Ramakers and Frank J. Melillo (see below).

November 25th revealed two small groups rotating into view that were not yet numbered. Space Weather Prediction Centre reported that “AR2785 is 110 millionths and Cso(Beta) while AR2786 is at 800 millionths and Fko (Beta/Gamma)”. The associated auroral display produced the purple glow known as “Steve” (discovered by Canadians 10 years ago), a river of gas with temperatures of 3,000º C passing through the Earth’s magnetosphere faster than 13,000 miles/hour. In an article at spaceweather.com published November 22nd it appears that “Steve” now has green cannon balls under a sequence of vertical pillars dubbed “the green picket fence”.

As CR2237 was drawing to a close AR2786 was growing larger and producing C class flares on November 26th. Two days later an M class flare came from the backside of the sun originating from spots had not rotated into view yet. AR2786 (beta/gamma) was breaking up with light bridges.

So, all in all a very exciting and interesting month for sunspot and Solar activity. We are definitely in Solar Cycle 25!

Thanks to the following Observer’s who submitted their sketches (S) and digital images (D) which are now archived in the A.L.P.O Solar Gallery for CR2237:

Theo Ramakers [D]
Howard Eskildsen [D]
Frank J. Melillo [D]
Dave Tyler [D]
Randy Tatum [D]
Paul Andrew [D]
Christian Viladrich [D]
Tony Broxton [S]
Guilherme Grassmann [D]
Geert Vandenbuicke [D]
Monty Leventhal [S]
David Teske [D,S]
Rik Hill [D]
Vlamir da Silva Junio [D]

November 15, 2020

Brief Summary of CR 2236

By Kim Hay
ALPO Solar Assistant Coordinator

CR2236 started on October 5, 2020 at 00:18 UT and ended on November 1 at 07:20 UT.

The uptick in the number of Cycle 25 sunspots that were produced made for an exciting month. Sunspot Numbers for the rotation were AR2274 through AR2279. The graph below shows the daily counts based on data reported by Spaceweather.com and the SILSO World Data Centre – Royal Observatory of Belgium.

There were several CMEs that produced a range of C1 and C4 class flares. On October 28th one CME had enough energy to produce M class flares while exhibiting a Beta-Gamma magnetic field.

On October 26th sunspot AR2778 appeared, initially spanning over 90,000 km. Within 24 hours it grew to 100,000 km in size. As reported by Solar observer Theo Ramakers in his rotation summary report, “Total Active Region Area for AR2776 was 420 millionths with the maximum daily area of 110 millionth on October 19th. AR2778 however, which developed much faster, accounted for 830 millionths for its short appearance in CR2236 of the Total Active Region Area for the Rotation of 2000 millionths.” For those interested in learning how to calculate the millionths of sunspots please reference the following article by Peter Meadows of the BAA available on the SAO/NASA Astrophysics Data System

Cycle 25 sunspot AR2776 also displayed an “Ellerman Bomb” on October 18th and was captured by both Theo Ramakers and Howard Eskildsen in images they submitted to the ALPO Solar Gallery. Per Wikipedia, an Ellerman Bomb involves “randomly moving filaments as two oppositely charged ion flows meet the Sun’s photosphere.” These are micro flares which are named after Ferdinand Ellerman who studied the Solar Blasts in the early 20th century. Great work by Howard and Theo capturing this event!

Ellerman Bomb Captured October 18

Images & Sketches can be found on the Solar ALPO image gallery for CR2236 from the following individuals:

Theo Ramakers
Howard Eskildsen
Frank J. Melillo
Guilherme Grassmann
Geert Vandenbuicke
Monty Leventhal (sketch)
David Teske (sketch)

October 21, 2020

Carrington Rotation 2235 Reports

Summary of CR2235 (September 7th to October 4, 2020)

By Acting Associate Coordinator – Kim Hay

On September 15th NASA/NOAA stated that Cycle 24 hit rock bottom in December 2019, which meant that we were heading into Cycle 25.

During this rotation there was a very inactive display of sunspot groups or spots. On September 9-10th there was a small area from a Cycle 25 active region that was active but did not produce any sunspots. A proto-sunspot from Cycle 25 showed up on September 14th then dissipated.

September 21st had an active region that rotated into view from the far-side. By September 23rd plage had shown up on the east limb. This area continued across the Sun and showed up in H-alpha and Calcium light as well as in the Magnetogram data until October 4th. There was a sunspot number (AR2273) assigned to this area, but it never produced a visual sunspot group seen in white light.

On September 24th there was a G1-class geomagnetic storm that produced green auroras in the higher latitudes for up to 4 nights. The Sun produced a flare that sent the solar wind towards Earth, impacting on September 29th and generating pink auroras.

The Sun went 34 days with no sunspots during this rotation period.

Thank you to our contributors and observers whose reports were referenced in creating this summary of CR2235: Monty Leventhal, David Teske, Theo Ramakers, Howard Eskildsen, Guilherme Grassmann. All images and sketches can be found in our ALPO Solar Gallery under CR2235.

A Brief Overview of CR2235

By Theo Ramakers

Carrington Rotation CR2235 covered the time period from 2020-09-07 1745 UT – 2020-10-05 0018 UT.

The observations can be viewed in my Solar Archive for CR2235 which can be accessed at: http://ceastronomy.org/gallery/main.php?g2_itemId=51093

The rotation brought us 25 spotless days and ended a spotless streak of 33 days on 9/24, which extended out of the previous rotation. We saw a small and very unstable new region AR2773, which appeared on two days, 9/24 and 9/26, each for less than 24 hours. Although its plage could be followed until it rotated around the Western limb, no spots were recorded for the rest of the rotation. The size of the Active Region was 10 millionths on both days, giving a Total Region Active Region Area of 20 millionth, while the largest Wolf Number of 13 was recorded on 9/25. Overall Solar Activity remained Very Low while the rotation increased the spotless days count since solar maximum to 851 spotless days. Finally, during the period SWPC reported 1 A-class, 19 B class flares, of which 14 happened on 9/21, and one C1.0-class flare. The C-class Flare, was observed on 09/25/2020.

This time I would like to feature some images showing the plage of the old AR2773 on three consecutive days, before it turned to the far side of the Sun.

September 14, 2020

CR 2234 Summary

By Kim Hay
Acting Assistant Coordinator

Carrington Rotation CR2234 started on 2020-08-11 1150 UT and ended on 2020-09-07 1745 UT.

On July 26th sunspot AR2270 rotated onto the Sun in the northeast and remained on the Sun until August 14th. This group produced a C2 class solar flare from the decaying sunspot.

On August 12th sunspot AR2771, which was in the southern hemisphere group of Solar Cycle 25 regions showing on NASA’s magnetic map, was visually seen on August 13th but gone by August 15th.

August 16th the Sun produced a B1 class flare in the southern hemisphere but no spots were evident.

Sunspot AR2772 showed up August 18th in the northern hemisphere producing a CME that missed Earth on Aug 20th as per NASA’s STEREO A satellite.

On August 28th the Sun produced a minor G1 class geomagnetic storm that produced Arctic auroras with solar winds of 500 km/s hitting the Earth’s atmosphere. Auroras were observed again on August 31st for five straight days.

The Sun then remained blank to the end of CR2234, reflecting very low activity with our Sun still waffling between Cycle 24 and 25.

Images & Sketches can be found on the Solar ALPO image gallery for CR2234 from the following individuals:

Theo Ramakers
Howard Eskildsen
Frank J. Melillo
Guilherme Grassmann
Paul Andrew
Monty Leventhal (sketch)
David Teske (sketch)
Tony Broxton (sketch)

September 8, 2020

A Short Summary of CR2234

By Theo Ramakers

Carrington Rotation CR2234 covered the time period from 2020-08-11 1150 UT – 2020-09-07 1745 UT.

The observations can be viewed in my Solar Archive for CR2234 which can be accessed at: http://ceastronomy.org/gallery/main.php?g2_itemId=50864

The rotation brought us 21 spotless days, with a spotless streak of 17 days. The rotation showed us 3 named Active Regions AR2770, 71 and 72. AR2770 extended from the previous rotation for another 2 days. Another region which was named AR2771 was visible concurrently with AR2770 for one day. However the new region was short lived with 2 days only. A third region AR2772 was visible for 3 days starting on 08/19/2020. The regions were very small at 10 millionths, with AR2772 being the exception by growing to 20 millionths for one day on 08/20/2020, on which day also the maximum wolf number of 24 was observed. Overall Solar Activity remained Very Low with the total Active Region Area for the rotation measuring only 90 millionths, while the rotation increased the spotless days count since solar maximum to 825 spotless days. Finally, during the period SWPC reported 2 A-class, 13 B class, and no C-class flares. The largest B-Flare, a B3.9 was observed on 08/19/2020.

Even though that solar activity is Very Low, it is also interesting to note that 14 of the last 17 named Active Regions since January 1 of this year were Cycle 25 polarized.

This time I would like to feature some images showing an unnamed, interesting feature that passed by, towards the end of the rotation.

September 3, 2020

Summaries for Carrington Rotations CR2228-CR2230

By Theo Ramakers

A Short Summary of CR2230

Carrington Rotation CR2230 covered the time period from 2020-04-24 1529 UT – 2020-05-21 2100 UT.

The observations can be viewed in my Solar Archive for CR2230 which can be accessed at: http://ceastronomy.org/gallery/main.php?g2_itemId=49751

The rotation brought us 21 spotless days, with a spotless streak of 20 days which was interrupted for 6 days while showing 4 Active Regions. AR2760 emerged on 4/26/2020 and lasted the entire 6 days with the exception that it disappeared for a short time on 4/29. Another region which was named AR2761 showed only for part of a day one day earlier. All regions were very small at 10 millionths, with AR2761 being the exception by increasing to 20 millionths on 4/30 and 5/1. The maximum Wolf Number of 35 was reached on 5/1 when both AR2760 and 63 were reported with 2 spots each. Overall Solar Activity remained Very Low with a Total Rotation Active Region Area of 100 millionths, while the rotation increased the spotless days count since solar maximum to 759 spotless days. Finally, during the period SWPC reported two A-class, two B class, and no C-class flares.

This time I would like to feature some combination images showing some prominences at the SW rim.

A Short Summary of CR2229

Carrington Rotation CR2229 covered the time period from 2020-03-28 0857 UT – 2020-04-24 1529 UT.

The observations can be viewed in my Solar Archive for CR2229 which can be accessed at: http://ceastronomy.org/gallery/main.php?g2_itemId=49494

The rotation brought us 22 spotless days with a streak of 19 days. We had one Active Region, AR2759, which emerged on 3/31/2020 and lasted for 5 days. The region’s maximum coverage was 30 millionths on April 3 and 4, when it supported 2 and respectively 3 spots. Overall Solar Activity remained Very Low and the rotation increased the spotless days count since solar maximum to 738 spotless days. Finally, during the period SWPC reported three A-class, seven B class and no C-class flares.

At this time, I would like to feature some combination images showing AR2759 in three different wavelengths on three different days.

A Short Summary of CR2228

Carrington Rotation CR2228 covered the time period from 2020-03-01 0126 UT – 2020-03-28 0857 UT.

For two days on March 9th and the 10th, the rotation did bring a new active region AR2758. On March 9th as an Hrx, and 10th as a Cro area, however, its size did not exceed 20 millionths. I did not have the time to keep up with the Reverse Polarized Areas during this rotation, but will catch up for the next summary with a new reverse polarized area report. On March 28rd the current spotless streak stands at 18 spotless days. Overall Solar Activity remained Very Low and the rotation increased the spotless days count since solar maximum to 716 days. Finally, during the period SWPC reported three A-class, one B class and no C-class flares.

April 25, 2020

Carrington Rotations Commencement Date/Times for CR 2159-2306

A page with the dates & times of Carrington Rotations CR 2159 to 2306 (JAN 2015 thru DEC 2025) as calculated by Jeff Beish are now available using the page link on the right or using this link.

Clear Skies,
Rik Hill

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