Weekly Bulletin on Solar and Geomagnetic Activity Highlights on 09 - 15.12.2019, Forecast on 16 - 23.12.2019, Carrington Rotation 2224, 2225 (12,74.10 - 10,05.12.2019) Earth out of ecliptic (2.5 - 1.9) deg. (S25 - N25 is zone of geoeffectiveness) THE SUNSPOT-FORMING SOLAR ACTIVITY REMAINED VERY LOW WITH A SPOT- LESS VISIBLE DISK (270 SPOTLESS DAYS IN THE YEAR - 77%). ESTIMATED, MOST LIKELY WEEKLY AVERAGE VALUE OF THE RELATIVE SUNSPOT 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. ONE SOLAR FILAMENT EJEC- TION AND FOUR CORONAL MASS EJECTION (9-11.12) 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 13.12 >1023 >2215 N15E63L010 6 -------------------------------------------------------------------- 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 Spacecraft CH + N38L273 N25L256 N11L271 N20L256 <5.0% 16.12 7 G0 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. ---------------------------------------------------------------------- FROM 5.12/1730 UT, THE SIGN OF SECTOR IMF IS EXPECTED UNSTABLE AND CHAN- GES FREQUENTLY, BUT IN THE MIDDLE IT REMAINS WITH THE "-". IN THE FOLLOW- ING WEEK THE BEHAVIOR OF THE SECTOR SIGN NOT CHANGED, BUT TO GIVE A FORE- CAST BY EARTH'S PASSAGE OF CONFIDENT SECTOR BOUNDARY IS NOT POSSIBLE (DE- EP PHASE OF MINIMUM!). ----------------------------------------------------------------------- DECEMBER 09 10 11 12 13 14 15 DECEMBER Wus 000 000 000 000 000 000 000 F10.7 071 071 071 071 069 070 071 èbcg A7.9 A7.8 A7.7 A7.6 A7.5 á7.8 A7.8 GOES Sp 000 000 000 000 000 000 000 msh N IMF - + + - ~ -/~ -/~ DSCOVR Å>2 4.2E+6 3.3E+6 2.3E+6 3.2E+6 3.5E+6 5.3E+6 2.6E+6 GOES Ie>2 137 109 pfu Ap 4 4 6 4 4 2 5 nô Dst nô KIOTO Amsc 6 4 5 4 4 3 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 GOES-15 in (electrons/cm2.s.sr) for events > 1000 pfu. THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT HAVE NOT BEEN OBSERVED. NEXT WEEK THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSYNCHRONOUS ORBIT IS EXPECTED AFTER 19.12. THE GEOMAGNETIC CONDITION AT MIDDLE LATITUDES REMAINS UNSETTLED AND QUIET ALL DAYS. NEXT WEEK 18-19.12 THE EARTH WILL PASS A HIGH-SPEED STREAM OF THE SOLAR WIND FROM A RECURRENT CORONAL HOLE OF THE NORTHERN HEMISPHE- RE OF THE SUN. GROWTH OF A GEOMAGNETIC DISTURBANCE IN ENVIRONMENT IS POSSIBLE. THE PROBABILITY OF A MINOR MAGNETIC STORM IS ~ 30% (MORE PROBABILITY IS NOT A LONG-TERM SUBSTORM). 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