June 1, 2025 Halo CME Aurora

A fast halo CME*** struck Earth's magnetic field on June 1st at 11:42 PM MT (0542 UTC). I missed the first big outburst at 1:40 am but caught a lovely display just before twilight from 3:45 - 4:15 am. It was visible unaided and looked like faint bristles of pale light dancing along the horizon.

***A CME is a “coronal mass ejection”, and “fast” means a solar wind speed of greater than 1000km/s.

See the story at SpaceWeather.com