:Issued: 2010 Nov 29 1355 UTC :Product: documentation at http://www.sidc.be/products/bul #--------------------------------------------------------------------# # SIDC Weekly bulletin on Solar and Geomagnetic activity # #--------------------------------------------------------------------# WEEK 517 from 2010 Nov 22 SOLAR CONDITIONS --------------- During the past week, solar activity was quite low. The GOES X-ray flux was mostly at A-level, with a few isolated B-flares. On Nov 24, STEREO/COR2 and LASCO observed a CME around 4h24. This eruption however, did not affect the Earth. On the same day, the SDO/AIA 304 movie shows 3 filament eruptions. These were also not geo-effective. Several eruptions at the back of the Sun were observed on Nov 26 and Nov 27. GEOMAGNETIC CONDITIONS ---------------------- Geomagnetic conditions were quiet during the most of the week. The solar wind speed decreased from 500 km/s on monday Nov 22 to 350 km/s on Nov 27. Late on Nov 27 a shock in all solar wind parameters was observed due to the arrival of a recurrent coronal wind stream. This caused a short period of unsettled geomagnetic conditions: Kp reached a maximum of Kp=4. The solar wind speed increased again to around 500 km/s. The SIDC all quiet alert remained valid during the whole week --------------------------------------------------------------------------- DAILY INDICES DATE RC EISN 10CM Ak BKG M X 2010 Nov 22 041 016 75 006 A4.3 0 0 2010 Nov 23 029 012 75 011 A4.8 0 0 2010 Nov 24 012 008 76 008 A5.0 0 0 2010 Nov 25 025 015 78 004 A5.0 0 0 2010 Nov 26 024 014 76 002 A4.6 0 0 2010 Nov 27 024 012 77 018 A4.6 0 0 2010 Nov 28 /// 021 80 010 A6.5 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 # #--------------------------------------------------------------------#