:Issued: 2025 Mar 17 1246 UTC :Product: documentation at http://www.sidc.be/products/bul #--------------------------------------------------------------------# # SIDC Weekly bulletin on Solar and Geomagnetic activity # #--------------------------------------------------------------------# WEEK 1263 from 2025 Mar 10 Solar Active Regions (ARs) and flares --------------- Solar flaring activity was low to moderate during the week. A total of 48 C-class flares and 2 M-class flares were observed. The largest flares were two M1.1 flares, one peaking on March 11 at 13:04 UTC (SIDC Sunspot Group 431/NOAA Active Region 4024) and the second peaking on March 14 at 22:21 UTC (SIDC Sunspot Group 437/NOAA Active Region 4030). There were a total number of 22 active regions observed on the visible solar disk over the week. The number of active regions on disk increased from 5 to 13 during the week. Coronal mass ejections --------------------- During the past week, no CME (Coronal Mass Ejection) with an Earth directed component was observed. Coronal Holes --------------------- During past week, two negative polarity Coronal Hole (CH) crossed the central meridian on March 10, resp. on March 14 2025. Proton flux levels --------------------- The greater than 10 MeV GOES proton flux was below the 10pfu threshold for the entire week. Electron fluxes at GEO --------------------- The greater than 2 MeV electron flux was above the 1000 pfu threshold for almost the entire week. Solar wind --------------------- In the beginning of the week the solar wind at Earth transitioned from fast to slow, then on the March 12 the solar wind became fast again and returned to slow solar wind conditions on March 15. The solar wind ranged between 350 and 600 km/s and the interplanetary magnetic field was between 4 and 12 nT, and with the Bz reaching a minimum value of -11 nT. Geomagnetism --------------------- Geomagnetic conditions reached minor storm (KP5) on March 12 till March 14, with an isolated period of moderate storm on March 14 (Kp 6), and have since then returned to quiet conditions. --------------------------------------------------------------------------- DAILY INDICES DATE RC EISN 10CM Ak BKG M X 2025 Mar 10 111 104 149 009 B8.0 0 0 2025 Mar 11 /// 140 161 009 C1.0 1 0 2025 Mar 12 /// 157 160 029 C1.2 0 0 2025 Mar 13 /// 167 175 031 C1.1 0 0 2025 Mar 14 221 175 180 022 C1.2 1 0 2025 Mar 15 /// 167 178 014 C1.1 0 0 2025 Mar 16 /// 205 186 011 C1.1 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 SUMMARY DAY BEGIN MAX END LOC XRAY OP 10CM Catania/NOAA RADIO_BURST_TYPES 11 1303 1304 1306 ////// M1.1 ///4024 III/2 14 2218 2221 2232 ////// M1.1 ///4030 #--------------------------------------------------------------------# # Solar Influences Data analysis Center - RWC Belgium # # Royal Observatory of Belgium # # # # Website http://www.sidc.be. # # E-mail sidc-support@oma.be # # To unsubscribe http://www.sidc.be/registration/unsub.php # # # # Legal notices: # # - Intellectual Property Rights: # # http://www.astro.oma.be/common/internet/en/data-policy-en.pdf # # - Liability Disclaimer: # # http://www.astro.oma.be/common/internet/en/disclaimer-en.pdf # # - Use and processing of your personal information: # # http://www.astro.oma.be/common/internet/en/privacy-policy-en.pdf # #--------------------------------------------------------------------#