:Issued: 2023 Jun 06 0753 UTC :Product: documentation at http://www.sidc.be/products/bul #--------------------------------------------------------------------# # SIDC Weekly bulletin on Solar and Geomagnetic activity # #--------------------------------------------------------------------# WEEK 1170 from 2023 May 29 Solar Active Regions (ARs) and flares --------------- The week started with seven active regions visible on the solar disk, later in the week ten more active regions were visible, for a total of 17 throughout the week (NOAA ARs 3310 to 3326). The X-ray background was above the C-level all week. NOAA ARs 3315 and 3319 reached a beta-gamma-delta magnetic field configuration. Seven M-class flares occurred, on 30 May (NOAA ARs 3310 and 3315), 31 May (NOAA ARs 3319 and 3323), and 2 June (NOAA AR 3324). Coronal mass ejections --------------------- A filament eruption occurred in the southwestern quadrant of the Sun from around 08:30 UTC on June 4th. The associated coronal mass ejection (CME) was observed in SoHO/LASCO C2 coronagraph data from 10:36 UTC on June 4th. The CME was directed to the south-west and the bulk of the CME is not expected to be Earth directed. However, a glancing blow of the shock may impact Earth in the late evening of June 07 or in the first half of June 08. Coronal Holes --------------------- Two positive polarity, one at the equator (small) and one in the southern hemisphere, the corresponding high speed streams did not arrive to the Earth. Proton flux levels --------------------- Below threshold all week. Electron fluxes at GEO --------------------- Below threshold all week. Solar wind --------------------- The solar wind was slow throughout of the week. On 1 June it reached 500 km/s during some hours. The interplanetary magnetic field was below 10 nT the whole week except some brief peaks on 4 June, with mostly negative polarity (towards the Sun). Geomagnetism --------------------- The week was mostly quiet to moderate with the exception of some periods of K_Belgium and Kp reaching 4, on 31 May, 1 June and 4 June. --------------------------------------------------------------------------- DAILY INDICES DATE RC EISN 10CM Ak BKG M X 2023 May 29 169 157 154 005 B9.2 0 0 2023 May 30 220 165 162 006 C1.3 3 0 2023 May 31 /// 179 161 012 C1.8 4 0 2023 Jun 01 179 147 164 018 C1.5 0 0 2023 Jun 02 /// 139 162 006 C1.3 1 0 2023 Jun 03 /// 137 165 004 C1.4 0 0 2023 Jun 04 /// 141 168 012 C1.5 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 SUMMARY DAY BEGIN MAX END LOC XRAY OP 10CM Catania/NOAA RADIO_BURST_TYPES 30 0754 0810 0819 N00W00 M1.2 SF 93/3310 30 1015 1022 1029 ////// M1.3 210 93/3310 30 1336 1338 1341 S20W41 M1.4 1B 01/3315 III/2 31 0424 0438 0444 ////// M1.3 ///3323 31 1223 1226 1230 ////// M1.0 07/3319 31 2147 2208 2214 S07E81 M1.0 SF ///3323 31 2214 2252 2312 S07E81 M4.2 SF ///3323 02 0232 0241 0245 ////// M1.5 ///3324 #--------------------------------------------------------------------# # 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 # #--------------------------------------------------------------------#