Solar alert

Issued on 2023 May 22 1303 UTC

A fast full halo coronal mass ejection (CME) was first observed in LASCO/C2 chronograph imagery around 00:12 UTC on May 22nd. The CME has no on-disc signature and was possibly driven by a back-sided flaring activity. No impact on Earth is expected.

Issued on 2023 May 22 1323 UTC

Moderate geomagnetic storms were registered globally as measured by Kp NOAA in the period 18:00 to 24:00 UTC on May 21st. Locally over Belgium mostly active conditions were observed with a short isolated minor storm interval between 18:00 and 19:00 UTC on May 21st. The observed geomagnetic storms are related to a weak ICME arrival following a previously ongoing high speed stream. The interplanetary magnetic field reached a maximum value of 13.22 nT and a minimum Bz of -10.57 nT, while the solar wind velocity reached 657 km/s. Ionospheric disturbances and isolated post-storm depressions have been observed following the geomagnetic storms. Unsettled to active geomagnetic conditions are expected for the next 24 hours with further chances for minor to moderate storms thereafter with the anticipated arrival of a new high speed stream on May 23rd.

Reference for this alert

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