:Issued: 2010 Feb 16 1521 UTC :Product: documentation at http://www.sidc.be/products/bul #--------------------------------------------------------------------# # SIDC Weekly bulletin on Solar and Geomagnetic activity # #--------------------------------------------------------------------# WEEK 476 from 2010 Feb 08 SOLAR ACTIVITY -------------- Several M-flares occurred this week. The source region was NOAA AR 1045/Catania 40. NOAA AR 1046/Catania 41 was responsible for the M8.3 flare of Feb 12. The M6.4 flare of Feb 07, peaking at 02:34UT was associated with a plasma eruption which was Earth directed. The active region 1045 was at that moment located near the central meridian. The projected speed of the CME was calculated to be 339 km/s by CACTus, a software to automatically detect CMEs in LASCO images. On Feb 13, at the position N30E30, a coronal dimming and a running wave front in a series of EIT-images are visible. The event started at 12:36T. The dimming and the EIT wave are on-disk signatures of the ejection of a plasma cloud. CACTus detected a very small cloud at 14:06UT. The only flaring activity, a C9.5 flare, at that moment came from an active region at that moment behind the east limb. The flare and the coronal dimming/EIT-wave are probably not associated. However, CACTus spotted a partial halo CME with an projected speed of 306 km/s at 19:54UT. GEOMAGNETIC ACTIVITY -------------------- Geomagnetic activity was low this week. ACE data show the arrival of two magnetic structures. Early Feb 11, a jump in the magnetic field strength occurred. This structure is possibly linked with the CME associated with the M6.4 flare of Feb 07. The geomagnetic response was minor: Kp became 2. On Feb 15, another magnetic structure arrived. This can be redrawn to the partial halo CME seen on Feb 13. The Kp went up to 4 late Feb 15-early Feb 16. --------------------------------------------------------------------------- DAILY INDICES DATE RC EISN 10CM Ak BKG M X 2010 Feb 08 067 036 94 005 B2.7 4 0 2010 Feb 09 /// 036 91 004 B1.0 0 0 2010 Feb 10 073 037 91 004 B1.6 0 0 2010 Feb 11 047 029 94 007 B1.6 0 0 2010 Feb 12 041 024 96 006 B1.8 2 0 2010 Feb 13 058 029 94 005 B2.1 0 0 2010 Feb 14 /// 027 89 004 B1.6 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 08 0736 0743 0746 N26E05 M4.0 150 III/2 40 1045 location based on EIT 08 1157 1203 1206 N21W07 M1.1 40 1045 location based on EIT 08 1332 1347 1350 M2.0 40 1045 08 2101 2123 2128 N23W12 M1.0 SN III/1 40 1045 12 1119 1126 1128 N26E11 M8.3 1N 350 V/3 41 1046 12 1752 1808 1815 N28W53 M1.1 2F 40 1045 #--------------------------------------------------------------------# # 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 # #--------------------------------------------------------------------#