Weekly Bulletin on Solar and Geomagnetic Activity Highlights on 19 - 25.02.2018, Forecast on 26.02 - 05.03.2018, Carrington Rotation 2200, 2001 (27,28.01; 23.62.02.2018) Earth out of ecliptic (-6.0 - -5.5 deg. (S33 - N23 is geoeffectiveness zone) SUNSPOT-FORMING ACTIVITY WAS ON THE VERY LOW LEVEL THROUGH THE OUTLOOK PERIOD AND THE SUN WAS SPOTLESS (26 DAYS ON CURRENT YEAR). THE ESTIMATED, MOST LIKELY WEEKLY AVERAGE VALUE OF THE RELATIVE SUNSPOT NUMBER IN THE INTERNATIONAL SYSTEM (old) FOR THE PERIOD W = 000 (Wn= 000). NEXT WEEK THE LEVEL OF SUNSPOT ACTIVITY WILL BE ON THE VERY LOW. 25 FEBRUARY IN THE CENTER OF THE VISIBLE DISK THE NEW ACTIVE RE- GION WHICH CAN INTERRUPT THE PERIOD OF SPOTLESS DAYS HAS BEGUN TO EMERGE. LIKELY WEEKLY AVERAGE VALUE OF THE RELATIVE SUNSPOT NUM- BER IN THE INTERNATIONAL SYSTEM (old) FOR THE NEXT WEEK IS W=010+ 10/-10. FLARE ACTIVITY WAS ON THE VERY LOW LEVEL NO EJECTA OF SOLAR FILA- MENTS REGISTERED ON PERIOD. 2 CORONAL MASS EJECTIONS WERE OBSER- VED 19 AND 24.02. ---------------------------------------------------------------------- FLARES FROM M1 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 --------------------------------------------------------------------- NEXT WEEK THE FLARE ACTIVITY IS EXPECTED AT LOW AND VERY LOW 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 Space Obser. óî - N05L017 S05L032 S41L0117 S15L002 25.02 4 SOHO, SDO... Sch - CH Square in Mm**2 (in square megameters) near the central meri- dian on http://sdowww.lmsal.com/suntoday/; n/d - no data; R - solar rotations; EE-date of possible geomag. disturbance in the Earth's environment. G(0-5)-geoeffectivity in last solar rotation on the middle latitudes. A-active geomagnetic condition. ------------------------------------------------------------------------ AFTER 16.02/2040 UT EARTH IS IN "-" SECTOR OF INTERPLANETARY MAGNETIC FIELD. NEXT SECTOR BOUNDARY -/+ THE EARTH MUST PASS 31.02. FEBRUARY 19 20 21 22 23 24 25 FEBRUARY Wus 000 000 000 000 000 000 000 F10.7 069 068 068 068 068 068 067 èbcg á2.9 A2.4 A2.4 A2.2 A2.2 A2.1 A2.0 GOES Sp 000 000 000 000 000 000 000 msh N IMF - - - - - - - DSCOVR Å>2 3.2E+8 4.7E+8 3.0E+8 1.1å+8 3.9å+7 9.1å+7 1.1å+8 GOES Ie>2 13452 12611 7036 5739 1971 2614 2610 pfu Ap 18 4 3 12 17 8 3 nô Dst nô KIOTO Amsc 14 4 4 17 15 7 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 GOES15 in (electrons/cm2.s.sr) for events > 1000 pfu. THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT BEGUN AT 18.02 AND 19 - 26.02 HAVE BEEN OBSERVED. NEXT WEEK THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT IS EXPECTED TO BE ON HIGH LEVEL ON 26.02 - 01.03. GEOMAGNETIC CONDITION WAS AT QUIET TO ACTIVE LEVELS IN THE PERIOD. ACTIVE PERIOD 19.02 ASSOCIATED WITH PEEK WIND SPEEDS FROM A NEGATI- VE POLARITY HIGH SPEED STREAM CORONAL HOLES. A SUBSEQUENT ENHANCE- MENT IN SOLAR WIND SPEEDS FROM ANOTHER NEGATIVE POLARITY HIGH SPEED STREAM CH INCREASED GEOMAGNETIC FIELD ACTIVITY TO ACTIVE LEVEL ON 22 - 23.02. NEXT WEEK THE GEOMAGNETIC CONDITION IS EXPECTED UNSETTLED AND QUIET. 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