The past few weeks have been eventful on the Sun, with another energy burst ejected into space. Under favorable conditions, this could trigger a powerful G3-level geomagnetic storm on Earth, according to The Hill, writes UNN.
Details
On Saturday, the Space Weather Prediction Center (SWPC) of the U.S. National Oceanic and Atmospheric Administration (NOAA) reported an M8.1-class solar flare – "an eruption of energy from the Sun that typically lasts from a few minutes to several hours." This flare is considered "rarer" and weaker than the X-class flares observed in November, which led to aurora borealis sightings.
Late Saturday evening, the SWPC reported a full-halo coronal mass ejection (CME) associated with the flare. The coronal mass ejection is expected to collide with Earth on Tuesday, and, depending on the "orientation of the embedded magnetic field," could result in a G3-level storm.
When coronal mass ejections, which are actually "solar ejections" of plasma and magnetic material ejected into space, interact with Earth's atmosphere, they cause geomagnetic storms. Storms are rated on a five-point scale, similar to tornadoes.
Last month, G4-level storm conditions brought the aurora borealis to the northern hemisphere.
G3-level geomagnetic storms are known to also trigger the aurora borealis, but predicting geomagnetic activity can be difficult until the "ejection" approaches Earth.
The SWPC has issued a strong geomagnetic storm warning for Tuesday. To reach G3 level, the Kp index, used to measure the magnitude of geomagnetic storms, must be around 7, according to the SWPC scale.
According to the current SWPC forecast, the Kp index could reach this level on Tuesday around 11:00 AM Kyiv time and persist throughout the day. However, it is noted that strong daytime activity may prevent us from seeing the aurora borealis.