:Issued: 2010 Sep 13 1351 UTC :Product: documentation at http://www.sidc.be/products/bul #--------------------------------------------------------------------# # SIDC Weekly bulletin on Solar and Geomagnetic activity # #--------------------------------------------------------------------# WEEK 506 from 2010 Sep 06 SOLAR ACTIVITY -------------- Solar activity was very low over the whole week. Only two small active regions were observed. The Sun was spotless on Sept.8 and 9. There was only one significant flare (C3.3 on Sept.8) but the largest event of the week was a large filament eruption in the North-East quadrant of the Sun early on Sept. 11. This event produced a semi-halo CME. Two moderately fast solar wind streams pushed the solar wind speed to maxima of 450-500km/s on Sept.8 and 10, before declining by Sept. 11 until the end of the week. GEOMAGNETIC ACTIVITY -------------------- The Earth magnetosphere was quiet to unsettled from Sept.6 to Sept.9 due to the aforementioned solar wind streams. The Bz component of the interplanetary magnetic field stayed for a few hours at -5nT on Sept.8, causing locally active geomagnetic conditions. After Sept.9, the geomagnetic field became very quiet (Kp=0-1). A possible geomagnetic disturbance is expected on Sept.13 in association with the CME of Sept.11. --------------------------------------------------------------------------- DAILY INDICES DATE RC EISN 10CM Ak BKG M X 2010 Sep 06 035 015 80 011 B1.1 0 0 2010 Sep 07 016 009 76 014 A8.0 0 0 2010 Sep 08 000 000 75 016 A7.5 0 0 2010 Sep 09 000 000 74 006 A9.4 0 0 2010 Sep 10 022 000 75 002 B1.4 0 0 2010 Sep 11 012 007 78 001 B1.5 0 0 2010 Sep 12 /// 011 78 001 B1.2 0 0 # RC : Sunspot index (Wolf Number) from Catania Observatory (Italy) # EISN : Estimated International Sunspot Number # 10cm : 10.7 cm radioflux (DRAO, Canada) # Ak : Ak Index Wingst (Germany) # BKG : Background GOES X-ray level (NOAA, USA) # M,X : Number of X-ray flares in M and X class, see below (NOAA, USA) --------------------------------------------------------------------------- NOTICEABLE EVENTS DAY BEGIN MAX END LOC XRAY OP TENCM TYPE Cat NOAA NOTE #--------------------------------------------------------------------# # Solar Influences Data analysis Center - RWC Belgium # # Royal Observatory of Belgium # # Fax : 32 (0) 2 373 0 224 # # Tel.: 32 (0) 2 373 0 491 # # # # For more information, see http://www.sidc.be. Please do not reply # # directly to this message, but send comments and suggestions to # # 'sidctech@oma.be'. If you are unable to use that address, use # # 'rvdlinden@spd.aas.org' instead. # # To unsubscribe, visit http://sidc.be/registration/unsub.php # #--------------------------------------------------------------------#