Dear users, Happy New Year, already 24th in the 21st century, the year of the maximum 25th SA cycle. GOOD LUCK AND HEALTH TO YOU AND TO ALL YOUR NEAR AND DEAREST FAR! My weekly reviews and forecasts have been published for 33 years and cover the decline branch of 22, fully 23 and 24, and the growth branch of 25 solar cycles. The solar activity (SA) scenario I proposed is fully confirmed by the development of the 2-nd epoch of reduced SA and then, after the 25th cycle, three more cycles of this epoch will follow. Next 26 Só will be low, followed again by a cycle of medium and then again low values, but with signs of the approaching epoch of increased SA, which is well (comparatively) known to us. The transition cycle between epochs will be SC29. SA will return to the highest level that we observed in SC18-22. The background values of the total magnetic field will increase ~ twice, which will entail an increase in the average value of magnetic fields of all active phenomena on the Sun and, accordingly, in the entire heliosphere, significantly reducing level of cosmic rays, opening up the possibility of long-term interplanetary flights and the creation of space stations outside the Earth’s magnetosphere. Until the end of the 70s of the 21st century, the Sun will be quite, which is what we observe in the last two solar cycles... From January 1, 2024, for some time (no more than six months) I will publish only short monthly reviews of the development of the current SC, as usual on the first Monday of the month, which will include a list of all X-ray flare events of class M>/=1, solar filament ejections, geoeffective coronal holes, proton en- hancements with E>/=10 MeV with flux >/=1 pfu, periods of high-energy electron fluxes with E>2 MeV, list of magnetic storms and sector boundaries for the past month. If during this time I do not find anyone willing to continue this activity, it will be closed, because my strength and enthusiasm are no longer enough for this voluntary service. This activity requires the efforts of a team of at least 3 researchers. I am ready to provide the necessary full support and assistance to master all the intricacies. Sincerely, V. Ishkov 25 CYCLE OF SOLAR ACTIVITY, THE BRANCH OF RISE: THE PHASE OF MAXIMUM THE RELATIVE MONTHLY MEAN SUNSPOT NUMBER ON DECEMBER 2023 HAS MADE Wdec = 76.0 114.2(in new system) THAT GIVES FOR 42 MONTH (JUNE 2023) OF DEVELOPMENT CURRENT 25 SOLAR CYCLE THE SMOOTHED MONTHLY MEAN SUNSPOT NUMBER W*june = 83.1 125.0 - in new system W*may = 79.9 123.9 - in new system On July 1, 2015 Centre in Brussels moved to a new system of calcu- lation the relative number of sunspots and practically all of the values were replaced throughout the numbered series of Wolf numbers (see link). Daily, monthly average and smoothed values of W in the old system ~close to the true ones can be obtained by multiplying by k=0.665. THE BEGINNING OF 25 SOLAR CYCLE - I 2020 with W*=1.3; (1.8n) THE PHASE OF MINIMUM OF SOLAR CYCLE 25 - 2020 01 - 2021 10 MAXIMUM OF THE CURRENT 25 CYCLE III - VI 2024 - Wmax=90-100; (150n) THE END OF 25 SOLAR CYCLE (THE POINT OF MINIMUM) - I - VI 2031; PROVISIONAL DAILY INTERNATIONAL SUNSPOT NUMDER FOR DECEMBER 2023 (59 observatories): 1..123 6..133 11.. 89 16..131 21..150 26..111 31.. 53m 2.. 98 7..121 12.. 99 17..116 22..151 27.. 76 3..105 8..114 13..109 18..136 23..138 28.. 94 4..113 9..128 14..115 19..155M 24..115 29.. 82 5..115 10..125 15..118 20..150 25..113 30.. 65 THE MONTHLY MEAN OF OBSERVED RADIO FLUX OF THE 10 cm (2800 MHz) ON DECEMBER 2023, AND SMOOTHES ON JUNE 2023 F10.7dec = 159.3 F*10.7june= 159.5 THE MONTHLY MEAN OF GEOMAGNETIC Ap-index ON NOVEMBER 2023, AND SMOOTHES ON MAY 2023 Ap dec=9.7 Ap*june = xxx ------------------------------------------------------------------- 25 CYCLE OF SOLAR ACTIVITY, THE BRANCH OF RISE: THE PHASE OF MAXIMUM Weekly Bulletin on Solar and Geomagnetic Activity Highlights on 25 - 31.12.2023 Forecast on 01 - 08.01.2024 Carrington Rotations 2278-2279 (24.62.11-21.12.2023) Earth out of ecliptic (2.3 - -2.8 deg) (S30 - N30 is zone of geoefficiency) THE SUNSPOT-FORMING SOLAR ACTIVITY CHANGED FROM MODERATE TO LOW LEVELS. ESTIMATED, MOST LIKELY WEEKLY AVERAGE VALUE OF THE SUN- SPOT NUMBER IN THE INTERNATIONAL SYSTEM (V1) FOR PERIOD IS W=052 +13/-20 (Wn =078+20/-30). ON THE VISIBLE SOLAR DISC OBSERVED UP 7 SUNSPOT GROUPS AND UP 4 LOCALIZED ON THE SOUTH HEMISPHERE. NEXT WEEK SUNSPOT ACTIVITY EXPECTED ON THE LOW AND MODERATE LE- VELS. WEEKLY AVERAGE VALUE OF THE RELATIVE SUNSPOT NUMBER IN THE INTERNATIONAL SYSTEM FOR NEXT WEEK WILL W=80+40/-40. FLARE ACTIVITY WAS ON VERY HIGH AND LOW LEVELS. 1 FLARE WAS OF X-RAY CLASS X, ONE- CLASS M AND 64- CLASS C, 5 SOLAR FILAMENT EJECTION AND 59 CORONAL MASS EJECTIONS, 4 OF WHICH WERE TYPE II (angular width 90-180 deg), HAVE BEEN OBSERVED. ----------------------------------------------------------------- FLARES >M1 X-RAY CLASSES to tm te localization Class E(1-8A) AR RII/IV CME X-ray/Ïp J/m-2 31.12 1844 1912 1940 N04E73L152 M1.0 13536 31.12 2136 2155 2208 N04E73L152 X5.0/3B 13536 IV CMEII/2200 DSF (EPL) to te localization l deg. Fl AR CMEtype/to 30.12 0800 S35E60L304 >10 30.12 0800 N60W50L184 >10 31.12 0600 S40E65L297 ~10 CME 31.12 0900 N38W50L182 ~10 CME 31.12 1700 S52E68L300 ~10 CME ------------------------------------------------------------------- NEXT WEEK FLARE ACTIVITY WILL BE AT A LOW AND MODERATE LEVELS. ON THE VISIBLE SOLAR DISK THE FOLLOWING GEOEFFECTIVE CORONAL HOLES WERE OBSERVED: sign N end E end S end W end Sch EE R G Spacecrafts CH - N10L245 S30L278 S33L263 S10L240 4.8% 01.01 6 ííâ SDO, HINOTORI CH*- N50L224 N45L225 N35L262 N40L269 2.1% 02.01 1 - SDO, HINOTORI * - low geoeffectivity, the substorms with duration <6 h only. Sch - CH area in % solar hemisphere near the central meridian on https://www.solarmonitor.org/; n/d - no data; R - solar rotations; EE-date of possible geomagnetic disturbance in the Earth's environment. G(0-5)-geoeffectivity in last solar rotation on the middle latitudes. A-active geomagnetic condition. ---------------------------------------------------------------------- FROM 29.12/1140 UT THE EARTH MOVED TO THE "-" SECTOR OF THE INTERPLANE- TARY MAGNETIC FIELD. NEXT SECTOR BOUNDARY "-/+" EXPECTED 8.01. ----------------------------------------------------------------------- DECEMBER 25 26 27 28 29 30 31 DECEMBER Wus 098 094 078 083 092 048 055 F10.7 167 154 149 147 143 140 146 èbcg C1.0 C1.0 ÷7.1 B7.5 B7.7 D9.9 C1.1 GOES Sp 700 640 520 430 582 470 380 msh N 1 1 IMF + + + + +/- - - DSCOVR Å>2 3.1å+6 4.8E+6 9.4E+6 1.1E+7 6.9E+6 5.4å+6 4.2å+6 GOES Ie>2 177 240 321 363 321 299 199 pfU Ap 3 4 4 2 6 4 3 nô Dst nô KIOTO Amsc 4 4 4 5 5 5 3 nô IZMIRAN -------------------------------------------------------------------- Å>2 - Daily Electron Fluency e/(cm2-ster-day) with E>2 MeV. Ie>2 - the maximum intensity of electron flux on geostationary orbits for days according to GOES-18 in (electrons/cm*2/s.sr) for events F>1000 pfu. Pr>10 MeV: 31.12/1500 UT; max-2.12 pfu 1.01/0030; to be continued... A HIGH LEVEL OF FLUX OF HIGH-ENERGY ELECTRONS WITH E>2 MeV NO OBSERVED. NEXT WEEK A HIGH LEVEL OF HIGH-ENERGY ELECTRON FLUX WITH å>2 MeV MAY BE EXPECTED AFTER 2.01 THE GEOMAGNETIC CONDITION WAS QUITE ALL PERIOD. ON NEXT WEEK 1.01 THE EARTH WILL ENTER THE HIGH-SPEED STREAM OF THE LARGE NEAR-EQUATORIAL CORONAL HOLE OF “-” POLARITY. PRO- BABILITY OF A MINOR MAGNETIC STORM ~20%. 2.01 A DISTURBANCE WILL COME TO THE EARTH FROM A VERY LARGE FLARE 31.12, THE IMPACT WILL BE SLIDING. THE PROBABILITY OF A MAGNETIC STORM IS NOT MORE THAN 20%. ON THE REST OF DAYS, THE GEOMAGNETIC CONDI- TION WILL DEPEND ON THE GEOEFFICIENCY OF THE FLARE ACTIVITY OF A LARGE SUNSPOT GROUP (AR 13536), APPEARING FROM THE E-LIMB ON 31.12. HIGHLIGHT AND FORECAST COMPOSED FROM DATA: NOAA SWPC, BOULDER, USA http://www.swpc.noaa.gov, THE SOLAR INFLUENCES DATA ANALYSIS CENTRE, SIDC, BRUSSELS, BELGIUM http://sidc.oma.be/index.php3, THE IZMIRAN, MOSCOW, TROITSK, RUSSIA http://www.izmiran.ru V.Ishkov