Weekly Bulletin on Solar and Geomagnetic Activity Highlights on 11 - 17.12.2017, Forecast on 18 - 25.12.2017, Carrington Rotation 2198 (30,94.12.2017) Earth above the ecliptic (1.6 - 1.1) deg. (S30 - N30 is geoeffectiveness zone) SUNSPOT-FORMING ACTIVITY WAS ON THE VERY LOW LEVEL AND THE SUN WAS SPOTLESS AFTER 13.12 (98 SPOTLESS DAYS IN THE CURRENT YEAR). THE ESTIMATED, MOST LIKELY WEEKLY AVERAGE VALUE OF THE RELATIVE SUNSPOT NUMBER IN THE INTERNATIONAL SYSTEM (old) FOR THE PERIOD W = 002+6/-2 (Wn= 004+9/-4). ON THE VISIBLE SOLAR DISK ONE SMALL AND QUITE SUNSPOT GROUP HAVE BEEN OBSERVED. NEXT WEEK THE LEVEL OF SUNSPOT ACTIVITY WITH HIGH PROBABILITY WILL BE ON THE VERY LOW LEVEL AND THE SUN EXPECTEDTED BE SPOTLESS. MOST LIKELY WEEKLY AVERAGE VALUE OF THE RELATIVE SUNSPOT NUMBER IN THE INTERNATIONAL SYSTEM (old) FOR THE NEXT WEEK IS W=010+10/-10. THE FLARE ACTIVITY WAS AT THE VERY LOW LEVEL. 2 EJECTION OF SOLAR FILAMENT AND, ACCORDING TO DATA FROM SOHO AND STEREO CORONOGRAPHS, >7 CME HAVE BEEN OBSERVED. ---------------------------------------------------------------------- FLARES 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 14.12 0500 0515 S07E40L255 7 óíå 15.12 >1023 1229 >2231 S25E28L249 12 óíå --------------------------------------------------------------------- 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 + N50L347 N48L007 N12L302 N18L299 17900 11.12 3 SDO, SOHO... CH - S05L268 S28L298 S30L270 S15L263 14.12 6 SDO, SOHO... CH + N30L253 N23L258 S05L223 N15L220 15600 17.12 7 G0 SDO, SOHO... 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 04.12/0115 UT THE EARTH IS IN "+" SECTOR OF THE INTERPLANETARY MAG- NETIC FIELD. NEXT SECTOR BOUNDARY +/- EARTH SHOULD BE PASSED 0N 25.12. DECEMBER 11 12 13 14 15 16 17 DECEMBER Wus 013 013 000 000 000 000 000 F10.7 072 071 072 072 072 071 071 èbcg á4.3 á4.1 A4.0 A4.1 A3.9 A3.8 A3.9 GOES Sp 010 010 000 000 000 000 000 msh N IMF + + + + + + + DSCOVR Å>2 1.5E+7 6.9E+6 6.3E+6 1.0å+7 1.1å+7 8.8å+6 1.5E+7 GOES Ie>2 1405 341 235 248 276 192 901 pfu Ap 10 16 8 4 4 3 26 nô Dst nô KIOTO Amsc 11 16 8 4 5 3 23 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 HAS BE- GUN 6/1340 UT AND 6-11.12 WERE OBSERVED. NEXT WEEK THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS OR- BIT IS EXPECTED 18 - 25.12. GEOMAGNETIC CONDITION CHANGED FROM ACTIVE (12.12) TO UNSETTLED AND QUIET IN OTHER DAYS. HOWEVER AT THE END OF THE DAYS 17.02 ACCORDING TO THE CENTER IN BOULDER DATA THE BEGINNING OF THE MAGNETIC STORM WHICH STILL CONTINUES IS NOTED. ACCORDING TO IZMIRAN DATA THIS DIS- TURBANCE THERE WAS SUBSTORM (G1) LASTING LESS THAN 9 h. - GEOMAGNE- TIC POLE REACTION ON EARTH's PASSING OF THE HIGH-SPEED STREAM FROM TRANS-EQUATORIAL CORONAL HOLE "+" POLARITY. NEXT WEEK, THE GEOMAGNETIC CONDITION WILL CHANGE FROM ACTIVE 18 - 20.12 THOUGH PROBABILITY OF THE MAGNETIC STORM THESE DAYS ~60%, TO UNSETTLED AND QUIET IN OTHER DAYS. 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