Weekly Bulletin on Solar and Geomagnetic Activity Highlights on 11 - 17.01.2021, Forecast on 18 - 25.01.2021, Carrington Rotations 2239, 2240 (25,94.12.2020; 22,27.01.2021) Earth out of ecliptic (-1.3 - -1.8) deg. (S30 - N30 is zone of geoeffectiveness) THE SUNSPOT-FORMING SOLAR ACTIVITY REMAINED ON VERY LOW LEVEL. BEFORE 15.01 THE SUN WAS SPOTLESS (12 DAY AT 2021). ESTIMATED, MOST LIKELY WEEKLY AVERAGE VALUE OF THE SUNSPOT NUMBER IN THE INTERNATIONAL SYSTEM (old) FOR PERIOD W=4+10\-4 (Wn=7+16/-7). NEXT WEEK SUNSPOT ACTIVITY WILL BE FROM VERY LOW TO MIDDLE LEVELS. WEEKLY AVERAGE VALUE OF THE RELATIVE SUNSPOT NUMBER IN THE INTER- NATIONAL SYSTEM (old) FOR NEXT WEEK IS W=010+10/-10. FLARE ACTIVITY WAS AT VERY LOW LEVELS. 3 SOLAR FLARE OF X-RAY CLASS "B" AND ONLY TWO CORONAL MASS EJECTIONS (11 AND 17.01) HA- VE 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 -------------------------------------------------------------------- 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... * - 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 17.01/0045 UT, THE EARTH IS IN THE "+" SECTOR OF THE INTERPLANE- TARY MAGNETIC FIELD. AT THE PERIOD 11-15.01 THE SIGN OF SECTOR WAS "-". THE FOLLOWING SECTOR BOUNDARY "+/-" IT CAN BE EXPECT 24.01.21 ---------------------------------------------------------------------- JANUARY 11 12 13 14 15 16 17 JANUARY Wus 000 000 000 000 013 015 023 F10.7 073 073 073 074 073 078 077 èbcg 2 1.9E+6 2.1å+6 1.9E+6 3.3E+6 2.7E+6 2.2E+6 2.1å+6 GOES Ie>2 166 154 168 261 223 168 189 pfu Ap 14 9 4 2 3 4 3 nô Dst nô KIOTO Amsc 17 8 4 2 3 4 2 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 OB- SERVED. NEXT WEEK THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT IS NOT EXPECTED. MINOR MAGNETIC STORM (G1, Ams=27, dur.=15 h) ACCORDING BOULDER CEN- TER DATA AND (G1, Ams=32, dur.=12 h) ACCORDING IZMIRAN DATA WAS RE- GISTERED AT 11-12.01 DUE TU SOLAR FILAMENT EJECTA (8.01) DISTURBAN- CE. IN OTHER DAYS THERE WERE QUITE GEOMAGNETIC CONDITION HAVE BE- EN 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