Solar Section

April 12, 2019

A Short Summary of Carrington Rotation 2215

Carrington Rotation 2215 covered the time period from 2019-03-12 1201 UT – 2019-04-08 1911 UT .
358 Images/Observations were submitted for the archives. The submissions can be viewed in ALPO’s Solar Archive for CR2215:

http://alpo-astronomy.org/gallery3/index.php/Solar-Observations-Archive/SolarImages2019/CR2215

The rotation brought us 4 active regions, AR2735, AR2736, AR2737, and AR2738, and 3 spotless streaks, one of 5, one of 6, and the last one of 3 days. The highest Daily Active Region Area for the rotation was 420 millionths on March 23, while the total active region areas for the rotation was 1470 millionths. The highest Wolf number for the rotation was 49 on March 22 when two active regions were visible at the same day. A number of small reverse polarized areas were observed around the last days of March and the beginning of April. See our overview with the last updates by clicking here. Overall Solar Activity remained Very Low and the rotation increased the spotless days count since solar maximum to 427. Despite this, during the rotation the Sun produced 70 B-class and 11 C-class flares.

This time we would like to feature some images submitted by three of our observers, Raffaello Braga, Theo Ramakers with a composite of AR2735 and AR2736 , and a WL image by Jeffrey Carels. Please click the thumbnails below to link to the images in the archive. Thanks to all contributors for another great rotation. Please take a look at all the drawings/images by clicking on the link above which will bring you to our archive for CR2215.
Clear Skies,
Theo Ramakers
Assistant Coordinator, the ALPOSS

April 9, 2019

Are we there yet?

Assistant Coordinator for the Solar Section of the ALPO, Theo Ramakers has been looking for some time to find and document, reverse polarized areas on the Sun, which might be an indication of Solar Cycle 25 activity. Granted that we are looking for large and named active regions with reverse polarization in the higher latitudes (approx. 30 degrees). However, smaller activities might give an indication of how we are getting on with this transition. In addition for them to be included in this summary, we needed to have an image in our archive which was submitted by one of our observers to be used in comparison to the SDO’s HMIB magnetograms. His article “Are we there yet”, appeared in the spring issue of ALPO’s Journal “The Strolling Astronomer”, which you can access here. In addition, you can stay up to date with this hunt for reverse polarized areas, since ALPO is making the summary document available on-line. This summary will be updated regularly and show these areas mapped to actual observer images for you to check out! To access the latest overview, please click on the image below which will load the pdf document containing the latest areas.

April 7, 2019

Reverse polarized areas

You are thinking that spotless days at the Sun are boring? Think again!!! Here three composites of images which have been submitted to the ALPO archive in the last week or so, which show evidence of a little (?) Cycle 25 activity. Although very miniscule, but they make themselves known. Since the polarization of the Sun switches with every cycle, we have been looking for reverse polarized areas on the Sun for a while, and have seen a good number of them. So here three composites showing this activity on images of our observers. Since the areas are very small and not even qualify to be called a pore or a plage, they have been cropped out of the full disk images which you can find in our Archive. The images to the right of them in the composite have been provided by SDO (Solar Dynamic Observatory) and show the polarization of these reversed polarized areas. (Northern hemisphere leading white (right), positive polarization; Southern hemisphere leading black, negative)

April 4, 2019

ALPOSS – A report on Carrington Rotation CR2206 through CR2209

ALPOSS Coordinator and Scientific Advisor Richard Hill continues his papers covering the analysis of the activity of the Sun’s Carrington Rotations using the images and reports submitted to the Solar Section with a report on: CR2206 thru CR2209. This report covers the period from 2018-08-06 0143 UT, thru 2018-10-26 2051 UT . The reports are based on over 951 image and observation submissions by numerous contributors to the Solar Observations Archive. The report was published in the 2019 Spring issue of the ALPO Journal, the Strolling Astronomer, and can now also be accessed as a standalone document on ALPOSS Solar Observations & Reports page, or by downloading it, by clicking on the picture below.

March 20, 2019

A Short Summary of Carrington Rotation 2214

Carrington Rotation 2214 covered the time period from 2019-02-13 0406 UT – 2019-03-12 1201 UT .
208 Images/Observations were submitted for the archives. The submissions can be viewed in ALPO’s Solar Archive for CR2214:

http://alpo-astronomy.org/gallery3/index.php/Solar-Observations-Archive/SolarImages2019/CR2214

The only Active Region for the rotation was AR2734, which was visible for 7 days. The rotation brought us 20 spotless days and also ended the longest spotless streak of the Cycle 24-Cycle 25 transition so far with 33 spotless days. The highest Daily Active Region Area for the rotation was only 30 millionths on February 7, while the total active region areas for the rotation was 110 millionths. The highest Wolf number for the rotation was 17 also on February 7th. A number of small reverse polarized areas were observed starting on the first day of the rotation followed on the 17th of February, and March 2 and 4th when we had two reverse polarized areas on the hemisphere. Most areas were in the southern hemisphere with latitudes between -2 and -20 degrees. Overall Solar Activity remained Very Low and the rotation increased the spotless days count since solar maximum to 413. During the rotation the Sun produced 3 C-class and 4 A-class flares.

This time we would like to feature some images submitted by three of our observers, Howard Eskildsen, Theo Ramakers, and a collage from Guilherme Grassman. Please click the thumbnails below to see the full images. Thanks to all contributors for another great rotation. Please take a look at all the drawings/images by clicking on the link above which will bring you to our archive for CR2214.
Clear Skies,
Theo Ramakers
Assistant Coordinator, the ALPOSS

February 16, 2019

A Short Summary of Carrington Rotation 2213

Carrington Rotation 2213 covered the time period from 2019-01-16 1954 UT – 2019-02-13 0406 UT .
210 Images/Observations were submitted for the archives. The submissions can be viewed in ALPO’s Solar Archive for CR2213:

http://alpo-astronomy.org/gallery3/index.php/Solar-Observations-Archive/SolarImages2019/CR2213

The rotation showed one Active Region, AR2733, which lasted for 9 days. 19 Days no sunspots were observed. The highest Daily Active Region Area for the rotation was 90 millionths on, January 28, January 30, and January 31, while the total active region areas for the rotation was 560 millionths. The highest Wolf number for the rotation was 27 on January 27. Four reversed polarized areas (cycle 25) were observed during the period. The first one on February 6th and the remaining 3 on the last three days of the rotation. Our archive shows three images that show the mentioned regions. Overall Solar Activity remained Very Low and the rotation ended with spotless day 393. During the rotation the Sun produced 41 C-class and 5 B-class flares.

This time we would like to feature some images submitted by three of our observers, Gabriel Corban, as well as Talha Moon Zia with a nice collage of AR2733 and David Teske’s drawing. Please click the thumbnails below to see the full images. Thanks to all contributors for another great rotation. Please take a look at all the drawings/images by clicking on the link above which will bring you to our archive for CR2213.
Clear Skies,
Theo Ramakers
Assistant Coordinator, the ALPOSS

January 28, 2019

A Short Summary of Carrington Rotation 2212

Carrington Rotation 2212 covered the time period from 2019-12-20 1152 UT – 2019-01-16 1954 UT .
217 Images/Observations were submitted for the archives. The submissions can be viewed in ALPO’s Solar Archive for CR2212:

http://alpo-astronomy.org/gallery3/index.php/Solar-Observations-Archive/SolarImages2018/CR2212

The rotation showed one Active Region, AR2732, which lasted for 6 days. For 21 days no sunspots were observed. The highest Daily Active Region Area for the rotation was 90 millionths on January 4 while the total active region areas for the rotation was only 200 millionths. The highest Wolf number for the rotation was 16 also on January 4. Two small areas showing Cycle 25 polarization could be seen on December 27 in Eskildsen’s CaK images at a latitude of North 46 degrees as well as on January 2nd at a latitude of South 28. Because of their sizes, the regions were not named. Overall Solar Activity remained Very Low and the rotation ended with Spotless Day 374, one C-class and 10 B-class flares.

This time we would like to feature some images submitted by three of our observers, Dave Tyler’s close up of AR2732, as well as Guilherme Grassman and Howard Eskildsen’s CaK images. Please click the thumbnails below to see the full images. Thanks to all contributors for another great rotation. Please take a look at all the drawings/images by clicking on the link above which will bring you to our archive for CR2212.
Clear Skies,
Theo Ramakers
Assistant Coordinator, the ALPOSS

January 12, 2019

A Short Summary of Carrington Rotation 2211

Carrington Rotation 2211 covered the time period from 2018-11-23 0411 UT – 2018-12-20 1152 UT.
192 Images/Observations were submitted for the archives. The submissions can be viewed in ALPO’s Solar Archive for CR2211:

http://alpo-astronomy.org/gallery3/index.php/Solar-Observations-Archive/SolarImages2018/CR2211

The rotation had four Active Regions, AR2728 which lasted two days, AR2729 five, AR2730 one, and finally AR2731 with two days. For 17 days no sunspots were observed. The highest Daily Active Region Area for the rotation was 60 millionths on December 7th while the total active region areas for the rotation was only 230 millionths. The highest Wolf number for the rotation was 16 on December 8th. During the rotation, an area showing Cycle 25 polarization could nicely be seen on December 16th in Eskildsen’s CaK image at a latitude of South 20 degrees. Because of its short life, the region was not named. Overall Solar Activity remained Very Low and the rotation ended with Spotless Day 352 and no C-, M- or X-class flares.

This time we would like to feature some images submitted by three of our observers, Frank Melillo, Guilherme Grassman, and Howard Eskildsen’s CaK image with the December 16th Cycle 25 polarized area. Please click the thumbnails below to see the full images. Thanks to all contributors for another great rotation. Please take a look at all the drawings/images by clicking on the link above which will bring you to our archive for CR2211.
Clear Skies,
Theo Ramakers
Assistant Coordinator, the ALPOSS

December 17, 2018

ALPOSS – A report on Carrington Rotation CR2202 through CR2205

After a break in the fall issue of the JALPO, ALPOSS Coordinator and Scientific Advisor Richard Hill continues his papers covering the analysis of the activity of the Sun’s Carrington Rotations using the images and reports submitted to the Solar Section with a report on: CR2202 thru CR2205. This report covers the period from 2018-03-22 2229 UT, thru 2018-07-09 2038 UT. The reports are based on over 882 image and observation submissions by numerous contributors to the Solar Observations Archive. The report was published in the 2019 Winter issue of the ALPO Journal, the Strolling Astronomer, and can now also be accessed as a standalone document on ALPOSS Solar Observations & Reports page, or by downloading it, by clicking on the picture below.

December 7, 2018

A Short Summary of Carrington Rotation 2210

Carrington Rotation 2210 covered the time period from 2018-10-26 2051 UT – 2018-11-23 0411 UT.
At the time of this writing 263 Images/Observations were submitted for CR2210. All submissions can be viewed in:
ALPO’s Solar Archive for CR2210: http://alpo-astronomy.org/gallery3/index.php/Solar-Observations-Archive/SolarImages2018/CR2210
The rotation was mostly spotless while accumulating 19 spotless days, but had two named active regions, AR2726 which lasted three days, and AR2727 with 5 days. The highest Daily Active Region Area for the rotation was 60 millionths on November 18 and 19 during AR2727. The highest Wolf number for the rotation was 14 on November 17 and 19. During the rotation, two areas showing Cycle 25 polarization could be seen in SDO’s magnetogram in the higher Northern latitudes. The first one from November 8th through 10th. The second for a number of hours on November 17th. Based on its naming requirements, SWPC did not name either of these areas, but SILSO took exception and did count them as spots. During the rotation, the sun produced a total of 6 A-class flares of which the largest was an A 5.3 class flare. Overall Solar Activity remained Very Low and the rotation ended with Spotless Day 335.
At this point I would like to clarify some statistics. Several organizations keep records of sunspots and the Sunspot Number. ALPO-Astronomy does not. My research, which I cite in these short reviews, contains data derived from published data from SWPC, which is a division of NOAA. This division is responsible for naming Active Regions (numbering). SILSO and the Solar-Terrestrial Center for Excellence are organizations tasked with the creation and dissemination of the Sunspot Number. They are connected to the Royal Observatory in Brussels Belgium. In addition, several other and country based organizations maintain their local Sunspot Numbers. Since I use other data than the Wolf Number such as active region areas and flares, I base my statistics on the raw data supplied by SWPC daily. One of them is their SRS reports which are published daily at 0030 UT. This is the reason why my sunspot related statistics may differ from others cited elsewhere.
This time we would like to feature some images submitted by three of our observers Guilherme Grassman, Howard Eskildsen with the November 8th Cycle 25 spot, and Theo Ramakers with the November 17th Cycle 25 area in Ha. Please click the thumbnails below to see the full images. Thanks all contributors for another great rotation. Please take a look at all the drawings/images by clicking on the link above which will bring you to our archive for CR2210.
Clear Skies,
Theo Ramakers
Assistant Coordinator, the ALPOSS

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