25 CYCLE OF SOLAR ACTIVITY, THE BRANCH OF RISE: THE PHASE OF MINIMUM Weekly Bulletin on Solar and Geomagnetic Activity Highlights on 11 - 17.04.2022, Forecast on 18 - 25.04.2022 Carrington Rotations 2556 (3,81.04.2022) Earth out of ecliptic (1.0 - 1.5) deg. (S35 - N25 is zone of geoeffectiveness) THE SUNSPOT-FORMING SOLAR ACTIVITY CHANGED FROM LOW TO MIDLLE LE- VELS. ESTIMATED MOST LIKELY WEEKLY AVERAGE VALUE OF THE SUNSPOT NUM- BER IN THE INTERNATIONAL SYSTEM (old) FOR PERIOD IS W=26+21/-12 (Wn= 44+34/-11). THERE ARE ON VISIBLE SOLAR DISK UP 5 SUNSPOT GROUPS, ONE OF THEM WAS THE AVERAGE SIZE AND ONE WAS ON SOUTH HEMISPHERE, HAVE BEEN OBSERVED. NEXT WEEK SUNSPOT ACTIVITY EXPECTED AT MEDIUM AND POSSIBLY HIGH LE- VELS SO FROM THE EASTERN LIMB IN THE NORTHERN HEMISPHERES 16.03 A COMPLEX OF ACTIVE REGIONS WITH HIGH FLARE ACTIVITY APPEARED - THE 2 ROTATION OF CAR 12975+76, WHICH PROVIDED TWO LARGE (1 CLASS X) AND 11 MEDIUM CLASS (M<5) FLARES ON THE PAST ROTATION. WEEKLY AVERAGE VALUE OF THE RELATIVE SUNSPOT NUMBER IN THE INTERNATIONAL SYSTEM (old) FOR NEXT WEEK IS W=070+50/-10. FLARE ACTIVITY WAS AT THE HIGH, MIDDLE AND LOW LEVELS. 1 FLARES X- RAY WAS CLASS "X", 6-CLASS "M", 45-CLASS "C", 19-CLASS "B", ONE SO- LAR FILAMENT EJECTION AND 29 CORONAL MASS EJECTIONS (11-12, 14-17. 04), THREE OF WHICH WAS OF TYPE "HALO" AND TW0 - 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 15.04 1031 1149 1229 N11E88L111 M2.2 1.5E-02 12994 15.04 1347 1359 1411 N14E88L111 M1.9 2.5E-02 12994 16.04 1449 1509 1456 N19E87L111 M1.0 8.5E-03 12993 17.04 0200 0223 0211 N20E83L111 M1.9 1.9E-02 12993 17.04 0317 0351 0334 N12E88L111 X1.1 1.4E-01 12994 II/2 óíå/0348 17.04 1952 2006 2002 S29W70L248 M1.5/SF 5.2E-03 12992 17.04 2228 2240 2234 S30W72L248 M4.4 1.7E-02 12992 DSF (EPL) to te localization l deg. Fl AR CME/to 15.04 >0052 >1403 S30W39L192 13 ------------------------------------------------------------------- NEXT WEEK THE FLARE ACTIVITY IS EXPECTED AT LOW, MIDDLE AND, MAY BE, HIGH LEVELS. ON THE VISIBLE SOLAR DISK THE FOLLOWING CORONAL HOLES WERE OBSERVED: --------------------------------------------------------------------- sign N end E end S end W end Sch EE R G Spacecraft * - 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. ---------------------------------------------------------------------- AFTER 13.04/0130 UT THE EARTH IS IN THE "+" SECTOR OF THE INTERPLANE- TARY MAGNETIC FIELD. FOLLOWING SECTOR BOUNDARY "+/-" IT CAN BE EXPECT 27.04. ----------------------------------------------------------------------- APRIL 11 12 13 14 15 16 17 APRIL Wus 024 023 037 037 035 078 074 F10.7 099 096 099 103 110 122 135 èbcg ÷2.3 ÷2.7 ÷1.7 ÷5.0 ó1.3 ó1.6 ó1.4 GOES Sp 020 120 060 120 160 730 970 msh N 1 1 1 1 3 IMF - - -/+ + + + + DSCOVR Å>2 2.2å+7 3.8E+7 3.8E+7 5.2E+6 2.1å+7 4.0E+7 5.4E+7 GOES Ie>2 995 1643 1415 771 641 1233 2314 pfu Ap 13 12 9 38 21 8 11 nô Dst -26 -80 -37 -25 nô KIOTO Amsc 11 16 5 30 19 10 10 IZMIRAN ------------------------------------------------------------------------ Å>2 - Daily Electron Fluency e/(cm2-ster-day) with E>2 MeV. Ie>2 - the maximum intensity of electron flux in geostationary or- bits in days according to GOES-15 in (electrons/cm*2/s.sr) for events > 1000 pfu. THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT BEGUN 12/1345 AND OBSERVED 12 - 13.04. NEXT THE FLUX BEGUN 16/1655 UT AND OBSERVED 16 - 17.04. NEXT WEEK THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT IS EXPECTED 18 - 19.04. THE GEOMAGNETIC CONDITION CHANGED FROM UNSETTLED TO LEVEL MINOR MAG- NETIC STORM (G2, Ams=30, dur.= 30 Þ) ACCORDING DATA OF BOULDER CENTER AND (G2, Ams=38, dur.=18 Þ) ACCORDING IZMIRAN DATA. THE SOURCE OF THE DISTURBATION WAS THE CME FROM FLARE OF CLASS ó1.6 11.04. NEXT WEEK THE GEOMAGNETIC CONDITION WILL BE CHANGING FROM UNSETTLED TO ACTIVE. SPORADIC MAGNETIC STORMS UP TO MAJOR ARE POSSIBLE AFTER 20.04. RECURRENT MINOR MAGNETIC STORMS ARE UNLIKELY. 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