Weekly Bulletin on Solar and Geomagnetic Activity Highlights on 8 - 14.04.2019, Forecast on 15 - 22.04.2019, Carrington Rotation 2215, 2216 (12,5.03; 08,8.04.2019) Earth out of ecliptic (-6.9 - -6.6) deg. (S30 - N20 is zone of geoeffectiveness) THE SUNSPOT-FORMING SOLAR ACTIVITY WAS AT THE LOW LEVEL. ESTIMATED, MOST LIKELY WEEKLY AVERAGE VALUE OF THE RELATIVE SUNSPOT NUMBER IN THE INTERNATIONAL SYSTEM (old) FOR PERIOD W = 8+1/-1 (Wn= 12+1/-1). ON THE SOLAR VISIBLE DISC ONE MIDDLE SIZE SUNSPOT GROUP IN WHICH NU- MEROUS THE X-RAY "B AND A"-FLARES WERE OCCURRED. NEXT WEEK THE LEVEL OF SUNSPOT ACTIVITY WILL AT VERY LOW LEVEL. LI- KELY WEEKLY AVERAGE VALUE OF THE RELATIVE SUNSPOT NUMBER IN THE IN- TERNATIONAL SYSTEM (old) FOR THE NEXT WEEK IS W=010+1/-10. FLARE ACTIVITY WAS AT THE VERY LOW LEVELS. NO FILAMENT EJECTION AND TWO CORONAL MASS EJECTIONS (10.4) 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 × ÇÒÁÄ. Fl AR CME/to -------------------------------------------------------------------- NEXT WEEK THE FLARE ACTIVITY IS EXPECTED AT LOW AND MIDDLE 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. 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 27.03/17 UT EARTH IS IN "-" SECTOR OF THE INTERPLANETARY MAGNE- TIC FIELD WITH OFTEN CHANGE OF SECTOR SIGN. NEXT SECTOR BOUNDARY -/+ THE EARTH MUST PASS 16.04. ----------------------------------------------------------------------- APRIL 08 09 10 11 12 13 14 APRIL Wus 012 012 013 013 014 014 011 F10.7 079 079 078 079 077 078 075 èbcg á6.0 á6.0 á2.2 á4.1 á2.4 á2.8 <á1.0 GOES Sp 250 300 350 260 300 300 250 msh N IMF - - - - - - - DSCOVR Å>2 1.8E+8 1.3E+8 2.5E+7 9.0å+7 9.9å+7 1.7E+8 1.9å+8 GOES Ie>2 23078 4297 3730 2706 2838 4636 4476 pfu Ap 13 11 14 7 9 8 4 nô Dst nô KIOTO Amsc 13 9 13 7 8 8 4 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. HIGH (and after 2.03 - extremal) THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT BEGAN 5.04/1400 UT AND 8 - 15.04 HAVE BEEN OB- SERVED. NEXT WEEK THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS OR- BIT IS EXPECTED 15-16.04. GEOMAGNETIC CONDITION AT MEDIUM LATITUDES UP REMAINS QUIET AND UNSET- TLED. NEXT PERIOD THE MOST PROBABLE QUIET AND UNSETTLED GEOMAGNETIC CONDI- TION 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