Weekly Bulletin on Solar and Geomagnetic Activity Highlights on 21 - 27.10.2019, Forecast on 28.10 - 3.11.2019, Carrington Rotation 2223 (16,44.10.2019) Earth out of ecliptic (5.7 - 5.3) deg. (S20 - N25 is zone of geoeffectiveness) THE SUNSPOT-FORMING SOLAR ACTIVITY REMAINED VERY LOW WITH A SPOT- LESS VISIBLE DISK ALL DAYS (224 SPOTLESS DAYS IN THE YEAR - 74%). ESTIMATED, MOST LIKELY WEEKLY AVERAGE VALUE OF THE RELATIVE SUN- SPOT NUMBER IN THE INTERNATIONAL SYSTEM (old) FOR PERIOD W=0 (Wn=0). NEXT WEEK THE LEVEL OF SUNSPOT ACTIVITY WAS ON VERY LOW LEVEL. LI- KELY WEEKLY AVERAGE VALUE OF THE RELATIVE SUNSPOT NUMBER IN THE INTERNATIONAL SYSTEM (old) FOR THE NEXT WEEK IS W=010+10/-10. FLARE ACTIVITY WAS AT THE VERY LOW LEVEL. TWO SOLAR FILAMENT EJEC- TION AND ONE CORONAL MASS EJECTION (25.10 back side event) HAVE BE- EN 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 × ÇÒÁÄ. Fl AR CME/to 22.10 >0007 >1341 S49E26L294 31 24.10 >1501 >0901 N51W62L179 8 -------------------------------------------------------------------- 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 Space Obser. CH + N45L306 N28L326 S28L309 N10L279 11.2% 25.10 5 G2 SDO, SOHO... 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. ---------------------------------------------------------------------- 23.09/09 UT THE INTERPLANETARY MAGNETIC FIELD SIGN IS UNSTABLE, BUT IN THE AVERAGE ARE REMAINED "+". THE NEXT SECTOR BOUNDARY THE EARTH MUST TO PASS 31.10. ------------------------------------------------------------------- ïCTOBER 21 22 23 24 25 26 27 ïCTOBER Wus 000 000 000 000 000 000 000 F10.7 064 066 065 065 069 069 069 èbcg á6.4 á6.4 á6.4 á6.5 A6.8 A6.8 á7.3 GOES Sp 000 000 000 000 000 000 000 msh N IMF + + + +/- - -/+ + DSCOVR Å>2 2.8E+6 3.5E+6 3.2E+6 5.8E+5 4.9E+8 4.6E+8 1.0å+9 GOES Ie>2 132 21151 20986 36223 pfu Ap 5 3 2 18 29 25 15 nô Dst -21 -40 -44 -30 nô KIOTO Amsc 4 6 3 24 21 27 14 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 BEGUN AT 25.10/0845 UT AND 25-27.10 HAVE BEEN OBSERVED. NEXT WEEK THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS OR- BIT IS EXPECTED 28.10-2.11. GEOMAGNETIC CONDITION AT MID-LATITUDES REMAINED QUIET UNTIL MID-DAY 24.10 WHEN THE EARTH ENTERED IN HIGH-SPEED SOLAR WIND STREAM FROM EQUATORIAL CORONAL HOLE "+" POLARITY. THIS PROVOKED THE MINOR MAGNE- TIC STORMS (G2, Ams=40, dur.=27 h.) 24-25.10 AND (G1, áms=30, dur.= 21 h.) 26 -27.09 ACCORDING TO THE CENTER IN BOULDER DATA. ACCORDING IZMIRAN DATA THIS MAGNETIC DISTURBANCES WERE INTENSIVE (G1) SUBSTORM (9 h.) 24.10, MINOR MAGNETIC STORMS (G0, Ams=27, dur.= 12 h.) 25.10, (G2, áms= 35, dur.=15 h.) 26.10 AND SUBSTORM (G0, dur.<6 h.) 27.10. NEXT WEEK THE MOST PROBABLY QUIET AND UNSETTLED GEOMAGNETIC CONDITION IS EXPECTED. 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