M-FLARE FROM AN UNEXPECTED SOURCE: Sunspot AR3331 exploded on June 9th (1711 UT), producing an M2.5-class solar flare.
A pulse of radiation ionized the top of Earth’s atmosphere. This, in turn, caused a minor blackout of shortwave radio transmissions over the Gulf of Mexico: map. Mariners may have noticed loss of signal at frequencies below 15 MHz for as much as 30 minutes after the flare.
Priviously, this sunspot was not thought to pose a threat for strong solar flares. AR3331 may have some tricks up its sleeve as it turns toward Earth this weekend.
https://spaceweather.com/
Ydun Ritz (2023-06-10)