Weekly Bulletin on Solar and Geomagnetic Activity Highlights on 22 - 28.04.2013 , Forecast on 29.04 - 05.05.2013, Carrington Rotations 2136 (17,78.04.2013) SUNSPOT-FORMING ACTIVITY OF THE SUN REMAINED ON THE AVERAGE LEVEL. WEEKLY, THE AVERAGE OF SUNSPOT NUMBER IN THE INTERNATIONAL SYSTEM FOR THE PERIOD WAS MADE W = 057+5/-7. ON THE VISIBLE SOLAR DISK CONSTANTLY WERE PRESENT FROM 3 TO 6 QUIET SUNSPOTS GROUPS, ONE OF WHICH WAS A BIG (AR11726, N13L323, Sp max=1000 m.v.h. ON 25.04) AND ONE A AVERAGE SIZE. NEXT WEEK THE LEVEL OF SUNSPOT ACTIVITY IS EXPECTED TO BE THE AVERAGE. THE CALCULATED MOST LIKELY WEEKLY AVERAGE VALUE OF SUNSPOT NUMBER IN THE INTERNATIONAL SYSTEM FOR THE NEXT WEEK IS EXPECTED W = 050+20/-10. FLARE ACTIVITY WAS AT THE AVERAGE LEVELAT 22.04 AND THE LOW - IN OTHER DAYS. 2 EJECTION OF SOLAR FILAMENTS ARE OBSERVED IN THIS PERIOD. BY SO- HO AND STEREO CORONOGRAPHS DATA THERE WERE OBSERVED SOHO 48 CME FROM WHICH TWO WERE THE TYPE OF "PARTIAL GALO III", AND FIVE WERE THE TYPE OF "PARTIAL GALO II". -------------------------------------------------------------------- FLARES to tm te c/p local. Class E(1-8A) AR RII/IV CME X / opt. J/m-2 22.04 1022 1029 >1034 N13W24L323 M1.0/ 2.3E-3 11726 CME DSF to te c/p local. l in deg. Fl AR CME 25.04 >1617 <0517 N21W16L246 7 26.04 >0925 <2324 S38W05L246 9 c/p local. - central part localization -------------------------------------------------------------------- NEXT WEEK THE FLARE ACTIVITY IS EXPECTED ON LOW AND AVERAGE LEVELS. ON THE VISIBLE SOLAR DISK THE FOLLOWING CORONAL HOLES WERE OBSERVED: --------------------------------------------------------------------- sign N end Å end S end W end EE R Observatories CH - N18L205 N08L197 N05L205 N10L210 02.05 2 KP, SDO, SOHO.. CH + S30L180 S40L150 S45L177 S32L188 03.04 3 KP, SDO, SOHO.. R - solar rotations; KP - KITT PEAK solar observatory; EE-date of possible geomag. disturbation in the Earth's environment. ---------------------------------------------------------------------- WITH 23.04/1830 UT EARTH WAS IN "-" SECTOR OF THE INTERPLANETARY MAGNE- TIC FIELD. THE FOLLOWING SECTOR BOUNDARY -/+ EARTH SHOULD TO PASS 5.05. APRIL 22 23 24 25 26 27 28 APRIL Wus 083 095 092 093 104 100 097 F10.7 113 118 115 119 122 127 132 èbcg ÷3.7 ÷4.9 ÷5.6 B7.3 ÷6.9 ÷8.4 B6.9 wt/m-2 GOES Sp 650 710 950 1450 1090 650 640 m.v.h. N 2 1 1 2 IMF - -/+ + + + + + áóå Å>2 1.5å+6 8.6E+5 6.7E+5 3.2å+6 2.7å+7 1.1å+8 1.1E+8 GOES Ie>2 157 843 2922 2698 GOES Nm% THULE Ap 4 6 19 8 18 5 4 nô áÒ Dst -4 -3 -52 -43 -35 -34 -21 nô KIOTO Amsc 6 9 18 13 16 12 12 nô IZMIRAN -------------------------------------------------------------------- Å>2 - a fluence in (electrons/cm2-day-sr) with E>2 MeV. Ie>2 - the maximum intensity of a flux of electrons in geostationary orbits in days according to GOES 15 in (electrons/cm2-s-sr) for events > 1000 p.f.u. THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSTATIONARY ORBIT VERY HIGH LEVEL BEGAN 27.04/0915 UT AND WAS OBSERVED 27 - 28 APRIL. THE GREATER THAN 2 MeV ELECTRON FLUX AT GEOSTATIONARY ORBIT VERY HIGH LEVEL IS EXPECTED 29 - 5.05. GEOMAGNETIC CONDITIONS WERE ACTIVE 24 AND 26 APRIL, AND ACCORDING TO IZMIRAN DATA 24.04 THE LEVEL OF DISTURBANCE EXCEEDED MINOR STORM THRE- SHOLD (G0, Ams= 24, dur.= 12 h.). In OTHER DAYS the GEOMAGNETIC CONDI- TIONS REMAINED UNSETTLED AND QUIET. NEXT WEEK THE GEOMAGNETIC CONDITION IS EXPECTED UNSETTLED AND QUIET. HIGHLIGHT AND FORECAST COMPOSED FROM DATA OF NOAA SWPC http://www.sec.noaa.gov, OF THE SOLAR INFLUENCES DATA ANALYSIS CENTER - SIDC, BELGIUM http://sidc.oma.be/index.php3, OF THE IZMIRAN, RUSSIA http://www.izmiran.ru