Weekly Bulletin on Solar and Geomagnetic Activity Highlights on 18 - 24.01.2021, Forecast on 25 - 31.01.2021, Carrington Rotations 2239, 2240 (25,94.12.2020; 22,27.01.2021) Earth out of ecliptic (-1.8 - -2.4) deg. (S32 - N28 is zone of geoeffectiveness) THE SUNSPOT-FORMING SOLAR ACTIVITY REMAINED ON VERY LOW AND LOW LEVELS. ESTIMATED, MOST LIKELY WEEKLY AVERAGE VALUE OF THE SUN- SPOT NUMBER IN THE INTERNATIONAL SYSTEM (old) FOR PERIOD W=15+8 \-7 (Wn=25+14/-12). ON VISIBLE SOLAR DISK THERE ARE THREE SMALL SUNSPOT GROUPS: TWO IN SOUTHERN AND ONE IN NORTHERN HEMISPHERE, HAVE BEEN OBSERVED. NEXT WEEK SUNSPOT ACTIVITY WILL BE ON LOW LEVEL. WEEKLY AVERAGE VALUE OF THE RELATIVE SUNSPOT NUMBER IN THE INTERNATIONAL SYSTEM (old) FOR NEXT WEEK IS W=020+10/-10. FLARE ACTIVITY WAS AT LOW LEVEL. 2 SOLAR FLARE OF X-RAY CLASS "C", 41 - "B", ONE SOLAR FILAMENT EJECTA (20.09) AND 11 CORONAL MASS EJECTIONS (20-22.01) HAVE BEEN OBSERVED. ------------------------------------------------------------------- FLARES >M1 X-RAY CLASSES to tm te local. Class E(1-8A) AR RII/IV CME X-ray/Ïp J/m-2 DSF to te localization l deg. Fl AR CME/to 20.01 20 - 21 SE CME/2124 -------------------------------------------------------------------- NEXT WEEK THE FLARE ACTIVITY IS EXPECTED AT VERY LOW LEVEL. ON THE VISIBLE SOLAR DISK THE FOLLOWING CORONAL HOLES WERE OBSERVED: --------------------------------------------------------------------- sign N end E end S end W end Sch EE R G Sp/craft CH + N60L054 N40L079 N25L054 N40L039 8.2 20.01 3 A SOHO... CH + S10L347 S20L352 S28L346 S22L334 1.5 24.01 2 SOHO... * - 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 18.01/17 UT, THE EARTH IS IN THE "-" SECTOR OF THE INTERPLANETA- RY MAGNETIC FIELD. 22/12-24/15 UT THE SIGN OF SECTOR WAS "+" THE FOLLO- WING SECTOR BOUNDARY "+/-" IT CAN BE EXPECT 30.01. ---------------------------------------------------------------------- JANUARY 18 19 20 21 22 23 24 JANUARY Wus 013 014 025 026 039 034 023 F10.7 075 078 077 078 078 078 078 èbcg A2.9 A4.1 A3.7 A5.7 á3.7 á2.9 A2.5 GOES Sp 120 120 110 110 100 070 060 msh N 1 1 IMF +/- - ~ - -/+ + +/- DSCOVR Å>2 2.1E+6 1.4å+6 1.6E+6 1.2E+6 1.3E+6 1.6E+6 1.4å+6 GOES Ie>2 398 - 187 207 120 224 194 pfu Ap 4 6 6 3 4 5 5 nô Dst nô KIOTO Amsc 5 5 4 2 3 3 5 nô 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/cm2.s.sr) for events > 1000 pfu. THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT NOT OBSERVED. NEXT WEEK THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT IS NOT EXPECTED. ALL DAYS THERE WERE QUITE GEOMAGNETIC CONDITION HAVE BEEN OBSERVED. IN THE NEXT WEEK THE MOST PROBABLE IS EXPECTED A QUITE AND UNSETT- LED GEOMAGNETIC CONDITION. 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