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Level S4 solar radiation event

swpc.noaa.gov

111–120 of 205 posts

Re: Level S4 solar radiation event

#111

Earlier quoted context omitted.

Just spend an hour outsite (Northern Germany, 01:00 MET). Unfortunately nothing to report, neither visual nor on camera. Maybe I just went to late and missed the show. I hope you habe more luck in Canada and the US!

It's pretty subtle right now here in NL but I can still see it with the naked eye. Mostly greenish haze that fades in and out.

ahh I just went outside (south of Utrecht) and saw nothing. Maybe too much light pollution.

Re: Level S4 solar radiation event

#112
post #85

Earlier quoted context omitted.

We are at kp 8.67. The Carrington event was a kp 9

Have we been having these more recently? I don't ever recall seeing these in the news so frequently. It feels like there are several a year now. A decade ago, never. And I also never remember seeing Aurora at my latitudes. Do we just have better sensing now, or is there some cycle on a period longer than a few years? Or maybe I'm crazy and just never noticed.

Mid to late 2025 was the peak of an 11 year solar cycle (25th one since we've started keeping track). We're on the trailing end of that peak activity now, which is why the past year/several months has seemed so active compared to recent years past, and should decrease significantly (in frequency and intensity) as 2026 progresses.

There was also a fairly significant geomagnetic storm back in November of 2025 as well.

You can see the data here at NOAA's Space Weather site https://www.swpc.noaa.gov/products/solar-cycle-progression

Re: Level S4 solar radiation event

#114

How rare is this? G4 storms are ~100 per solar cycle (~11 years). So roughly 9 G4 events/year on average.

Like 20-25 years rare according to some space weather youtuber.

> some space weather youtuber

Please stop watching that guy, he is a total fraud and knows nothing about physics.

Re: Level S4 solar radiation event

#115
post #83

Earlier quoted context omitted.

> Biological: Unavoidable radiation hazard to astronauts on EVA; passengers and crew in high-flying aircraft at high latitudes may be exposed to radiation risk. Anyone have a sense of magnitude for this advisory? How much more radiation should an airline passenger expect to receive during a G4 event than normal?

roughly up to 5-10 times the normal dose.

sounds "it's okey" ?

Re: Level S4 solar radiation event

#118
post #11

If anyone is interested in what "G4" means in context, here's the scale: https://www.swpc.noaa.gov/noaa-scales-explanation

We are at kp 8.67. The Carrington event was a kp 9

Disturbance storm time index (DST) is a better measure of peak intensity as KP is just a weighted average of the intensity from the last three hours across monitoring stations.

The May 2024 G5 electrical storm had a peak measured DST of −412 nT: https://en.wikipedia.org/wiki/May_2024_solar_storms

The Carrington Event had an estimated peak DST of −800 nT to −1750 nT, but no one really knows: https://en.wikipedia.org/wiki/Carrington_Event

Re: Level S4 solar radiation event

#119

Earlier quoted context omitted.

G4: " Induced pipeline currents affect preventive measures, HF radio propagation sporadic..." G5: " Pipeline currents can reach hundreds of amps, HF (high frequency) radio propagation may be impossible in many areas for one to two days..."

"Free Energy!"

That's the nice thing about solar power, but it's still a limited time offer
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