Earth to be Hit by Two Coronal Mass Ejections at Once on August 18, Posing Danger to Electrical Grid

A pair of large coronal mass ejections (CME) are expected to impact Earth’s magnetosphere on Thursday, bringing the potential for disruptions and damage to the electrical grid as well as spacecraft in orbit.

According to the latest forecast model by the US National Oceanographic and Atmospheric Administration (NOAA) on Tuesday, two CMEs that left the Sun on Sunday and Monday will reach Earth by Thursday. The first is a cloud of dark plasma, the second is a magnetic filament that could overtake the first and “cannibalize it,” posing a danger of geomagnetic storms.

The plumes are blamed on increased activity on the Sun’s surface as the star reaches its 11-year solar maximum. CMEs have hit our planet several times in the last few months, thanks to the uptick in eruptions.

According to NOAA, the CMEs could cause either minor G1 geomagnetic storms or more serious G2-class storms, with the ability to trigger power grid fluctuations, blow out transformers, and trigger voltage alarms on high-altitude power systems, if it lasts for a long period of time. They are also likely to impact spacecraft operations, radio communications, and of course, produce beautiful aurorae that will light up the night sky.

With the sunspot that produced both CMEs still facing Earth, there’s still a possibility that more flares could soon be on their way. NOAA gives a 30% chance of a medium-sized flare and a 10% chance of a large flare before the end of Wednesday.

However, they will likely pale in comparison to the worst solar storm to ever impact the Earth, known as the Carrington Event in 1859. That massive storm caused aurorae so powerful they could be witnessed near the equator, caused telegraph lines to spark and to shock their users, and allowed operators to send signals despite their power systems being turned off.