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.

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.