:Issued: 2010 Mar 29 1157 UTC :Product: documentation at http://www.sidc.be/products/bul #--------------------------------------------------------------------# # SIDC Weekly bulletin on Solar and Geomagnetic activity # #--------------------------------------------------------------------# WEEK 482 from 2010 Mar 22 SOLAR ACTIVITY ------------- Solar activity was mostly quiet in the beginning of the week. Starting from March 27, activity picked up with several C-flares, originating from NOAA AR 1057. This NOAA AR 1057 (Catania 54) was the most prominent active region on the solar disk this week. The largest solar flare it launched was a C3.8 flare, peaking at 18h29 on March 27. A CME originating from the same location was detected by LASCO at 00h30 on March 24. STEREO-A data showed it was partially earth-directed. Because of this increased chance for C-flares and the possible geomagnetic disturbance of the CME, the SIDC all quiet alert was halted on March 24. On March 26, another earth-directed CME was detected by both STEREO spacecrafts at 08h39. GEOMAGNETIC ACTIVITY ------------------- There were no big geomagnetic disturbances during the week. The maximum level Kp reached was 3 and this happened during only one period on March 28. The solar wind speed was very low (~300 km/s) at the beginning of the week. On March 25, there was a jump in all solar wind parameters due to a sector crossing. The wind speed went up to ~430 km/s. For the rest of the week, the geomagnetic conditions were quiet to unsettled, also due to the influence of a coronal hole that crossed the central meridian on March 23 and the arrival of the CME that was detected on March 24. --------------------------------------------------------------------------- DAILY INDICES DATE RC EISN 10CM Ak BKG M X 2010 Mar 22 021 011 82 000 A3.1 0 0 2010 Mar 23 /// 008 84 002 A5.2 0 0 2010 Mar 24 015 010 84 004 A4.8 0 0 2010 Mar 25 025 016 86 008 A6.0 0 0 2010 Mar 26 030 014 88 005 A4.7 0 0 2010 Mar 27 036 021 88 /// A6.5 0 0 2010 Mar 28 /// /// 86 /// A4.5 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 # #--------------------------------------------------------------------#