The Mauna Loa K-Coronagraph observed 4 CMEs on August 30, 2022. K-Cor began observations at 17:11 UT and observed the tail-end of a CME in the southeast at ~155 degrees position angle (PA). This CME was recorded by the LASCO C2 coronagraph beginning ~15:12 UT. K-Cor also observed a CME in progress in the southwest at ~240 degrees PA. The outer edge of this 2 nd CME was still in the K-Cor field-of-view (FOV) at ~2 solar radii. This was followed by a bright structure that appeared at~17:42 UT in the very low corona at ~250 degrees. This bright feature erupted and formed the core of the 3 rd , and fastest, CME of the day. This loop-cavity-core CME was estimated to be moving at 970 km/sec in the K-Cor FOV by the time it reached 2.65 solar radii. It had an acceleration estimated at 567 m/sec^2. The plot shows the K- Cor time-height measurements and the estimates of speed and acceleration. The data gap in the K-Cor time-height plot is due to clouds moving over the observatory. This fast CME was first observed by LASCO at 18:12. The speed of the CME in the LASCO FOV was estimated at ~1400 km/sec. The 4 th CME of the day was located in the northeast at ~70 degrees PA and was first seen by K-Cor at ~21:13 UT.
The fast CME in the southwest encountered the Solar Orbiter spacecraft as Orbiter was approaching Venus for a gravity-assist fly-by. The in-situ instruments on Solar Orbiter recorded elevated levels of solar energetic particles. For more information about this fast CME encountering Solar Orbiter please see: https://www.esa.int/Enabling_Support/Operations/Coronal_mass_ejection_hits_Solar_Orbiter_before_ Venus_flyby