Solar alert

Issued on 2023 Dec 31 1320 UTC

A partial halo coronal mass ejection (CME) is detected in the LASCO/C2 imagery first lifting off the solar surface around 07:48 UTC on Dec 30th. The CME is associated with a small filament eruption in the south-east quadrant and related long-duration C2.6 flaring from NOAA AR 3534 (beta). Coronal dimming is observed in the SDO/AIA images after 08:00 UTC on Dec 30th. The nature of the filament eruption and lack of STEREO coronagraph data make it difficult to accurately estimate the CME speed, but the average projected velocity is around 400 km/s. While the bulk of the eruption is off the Sun-Earth line, a minor glancing blow could impact Earth during the UTC night of Jan 2nd or UTC morning of Jan 3rd. The Earth at that time is expected to be affected by an ongoing high speed stream, so any potential glancing blow arrival might be mixed with it.

Reference for this alert

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