On Friday, February 21, a near-top class M solar flare occurred on the Sun. This was reported by the Institute of Applied Geophysics (FSBI "IPG").
On February 21, at 15:15 Moscow time, an M3.3 flare with a duration of 14 minutes was recorded in the X-ray range.
Depending on the power of X-ray radiation, solar flares are divided into five classes — A, B, C, M, and X. The minimum class A0.0 corresponds to a radiation power of 10 nW per 1 sq. m in Earth's orbit.
Solar flares of class M are medium flares from the so-called large ones. In total, there are five categories in their gradation. But they cause radio interference on the daytime side of the Earth from a slight to moderate level.
Read materials on the topic:
Two strong flares occurred on the Sun
Coronal hole on the Sun threatens Earth again: increased solar wind is expected
"The Sun is starting to scare": the star "fired" eight strong flares in a day