New Delhi: On 20 August, there was a pair of spectacular prominence eruptions from the Sun on the eastern limb. The associated coronal mass ejections (CMEs)
were not aimed at the Earth, but were spectacular. In these violent eruptions, plasma or hot gas from the atmosphere of the Sun is hurled outwards into space by the reconfiguration of tangled magnetic fields. On encountering the Earth, the CMEs can induce geomagnetic storms and spectacular displays of polar lights. However, as the CMEs were not Earth-facing, they are unlikely to strike the Earth. The analysis and modelling of the CMEs through interplanetary space is ongoing.
The Space Weather Prediction Centre (SWPC) operated by the US National Oceanic and Atmospheric Administration (NOAA) in its forecast says, “Although not Earth-directed, two prominence eruptions were of note. Both emerged from on or just beyond the eastern limb, as observed in GOES-16 SUVI 304 imagery at approximately 20/0424 and 20/0804 UTC, respectively.” According to the Australian Space Weather Forecasting Centre (ASWFC), “A prominence eruption was observed, visible in GOES SUVI imagery near S30E90 at 20/0424UT. A subsequent associated eastward CME was observed, visible in LASCO C2 coronagraph imagery from 20/0512UT. Modelling indicates this CME is not geoeffective. A second prominence eruption was observed, visible in GOES SUVI imagery near N35E90 at 20/0836UT. The subsequent associated CME observed at 20/1036UT in LASCO C2 coronagraph imagery is not considered to be Earth-directed.”
Space Weather Forecast
According to the South African National Space Agency (SANSA), “There are several filaments and prominences on the visible solar disk that show slight movement and will be monitored for any potential lift-offs. No Earth-directed coronal mass ejections (CMEs) were observed in the available coronagraph imagery during the past 24 hours.” A high speed stream (HSS) from a coronal hole is aimed straight at the Earth, which may induce a minor geomagnetic storm in combination with a glancing impact from a CME that erupted on 17 August.
