Ongoing discussion [0] (200 points, 6 hours ago, 199 comments), related Most of Europe is glowing pink under the aurora [1] (335 points, 2 hours ago, 95 comments)

[0]: https://news.ycombinator.com/item?id=40321821 [1]: https://news.ycombinator.com/item?id=40324179

It's back down to a G4 for now.

https://www.spaceweather.gov

* Solar wind currently has a mean delay of about 2.5 days. Light takes 504 seconds to reach us at this time of year.

The last G5 storm was in 2003

https://en.wikipedia.org/wiki/2003_Halloween_solar_storms

According to NOAA, this is the first G5. https://www.swpc.noaa.gov/news/g5-conditions-observed

It's written in an ambiguous way and you interpreted it incorrectly. "G5 Conditions were first observed at Earth at 6:54 p.m. EDT today." should be read like "today, G5 conditions where first observed at 6:54", not "G5 conditions where first observed today (at 6:54)".

G5 is defined as K_p = 9. That happened in Oct 2003. https://ftp.gwdg.de/pub/geophys/kp-ap/kp-freq/kp2003.frq

Thank you!