261 pointsby WorldPeas7 hours ago30 comments
  • jjcm4 hours ago
    If anyone is interested in what "G4" means in context, here's the scale: https://www.swpc.noaa.gov/noaa-scales-explanation
    • irthomasthomas3 hours ago
      We are at kp 8.67. The Carrington event was a kp 9
      • ianruh2 hours ago
        I am not an expert, but it’s worth noting that the kp index has a maximum value of 9. So though the Carrington event had a kp of 9, its intensity on the related (but not capped) HP30/HP60 scale [1] would likely have been higher. [1] https://kp.gfz.de/en/hp30-hp60
        • repeekad2 hours ago
          Queue Chernobyl documentary clip measuring the radiation as low because that’s as high the meter went
          • wyldfirean hour ago
            s/queue/cue/

            Though I suppose you could also queue it.

          • celsoazevedo2 hours ago
            3.6 roentgen. Not great, not terrible!
      • echelon2 hours ago
        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.

        • awesome_dudean hour ago
          We've just passed the 11 year peak - the sun spot activity has a period of around 11 years.
    • 8bitsrule2 hours ago
      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..."

      • gexlaan hour ago
        "Cool! What's G13 do?" - Bill Hicks

        Looks like G5 is the highest level and the scale system is used by NOAA.

      • gosub100an hour ago
        "Free Energy!"
    • non-2 hours ago
      > 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?

      • inatreecrown22 hours ago
        roughly up to 5-10 times the normal dose.
    • xeckr3 hours ago
      Looks like we get these for about 60 days for periods lasting 11 years.
    • neonmagenta3 hours ago
      so more of a 'bad storm here and there' level?
  • bartman4 hours ago
    We had intense aurora in Berlin, Germany. Green clouds dancing in the sky levels. Started around 22:10 local time or a bit earlier, and at this point there's only a faint red/green glow remaining.
    • rob743 hours ago
      Yeah, there were auroras even as far south as Munich. Maybe not as intense, but it's the first aurora I ever saw, so I can't really judge...
      • ccozan3 hours ago
        I am south-west of Munich and with a perfect clear sky I could only see stars, one meteor, and that's it.
    • fluxflexer3 hours ago
      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!
      • jacquesm3 hours ago
        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.
    • karim793 hours ago
      I was just out at a dog park and saw nothing! We have clear skies. I can't believe I missed this.
    • Tachyooon3 hours ago
      Could you see it from the inner city or only closer to the edges?
      • bartman2 hours ago
        Friends who live in Kreuzberg and Friedrichshain could see it pretty well. I'm a bit further south within Berlin where skies are minimally darker, but between 10pm and 11pm it was so bright that light pollution didn't matter.

        Funnily enough, despite having lots of alerts set up it was my mom who texted me from northern Brandenburg as she spotted it after getting an alert from RegenRadar, of all apps...

        • Tachyooon43 minutes ago
          It's amazing to hear it's visible in such a big city. I don't have a good intuition for all the metrics that describe how strong this storm was/is, but when put like this it hits home.

          Nice to hear earth weather apps also work great in space haha. I'll keep that in mind when I set up my own notifications. Hopefully I have time to look into it before the next storm hits.

    • paulmist4 hours ago
      Also seen in the Netherlands!
  • miduil5 hours ago
    Nice, you can already see some solar flares in Austria again.

    https://www.foto-webcam.eu/webcam/kleinfleisskees/

    https://www.foto-webcam.eu/

  • andrewinardeeran hour ago
    Any tips on best practices in how one can protect homelab rigs from a Carrington level event? Let's say we were given two days notice that the mother of all S4s was inbound. Just switch everything off?

    What if one of my homelabs needed 100% uptime to meet my wife's SLA for messaging? Is this able to be protected?

    • amluto21 minutes ago
      Not much? As I understand it, the major effects are in very long wires. Long wires can have get massive induced currents. But your homelab is unlikely to have long wires or very large loops. Ethernet wires are limited to 100m, and unshielded Ethernet is transformer-isolated to well over 1kV.

      Shielded Ethernet could plausibly have issues with induced current on the shield. PoE might be less immune than ordinary Ethernet depending on what you’re doing with it, although well-behaved devices should be isolated. If you have a cable ISP, the cable shield might get toasty, although it’s likely to be grounded close enough to your house that any damage will be upstream.

      Your 100% uptime will be tricky if your ISP goes down or you lose power.

    • idatum23 minutes ago
      Discontinue use of your telegraph system.

      Perhaps though you will still be able to continue to send and receive messages despite having disconnected your power supply. [1]

      [1] https://babel.hathitrust.org/cgi/pt?id=uva.x001679510&seq=40...

    • rootusrootus33 minutes ago
      AFAIK the risk is for long transmission lines. So your equipment at home is not really in any danger, as long as there is not a major surge on the transmission lines that makes it all the way to your house. If that happens, well, losing the home lab is probably no longer the issue.
  • frzen3 hours ago
    I had the most intensely coloured lights visible in the west of Ireland. I've seen them a few times before but never like this. Phones were capturing them in video not just long exposures.

    Not sure what the best service is to be alerted ahead of time. Apparently it'll be strong here again at 6am according to some of the apps some random people were waving around.

    • ortusdux3 hours ago
      There are several apps that do a good job of alerting users. I use "Aurora Pro", which I prefer because it checks cloud cover and lets you set alert thresholds based on viewing probability.
      • King-Aaron3 hours ago
        I woke up to a notification from aurora pro today, I'd forgotten I had the app. This would explain it
  • Animats4 hours ago
    PJM had some geomagnetic disturbance warnings, but did not progress to the alert stage or grid re-configuation actions. So, no US power grid problems.

        104955 Warning Geomagnetic Disturbance Warning 01.19.2026 14:30 
        PJM-RTO
        A Geomagnetic Disturbance Warning has been issued for
        14:30 on 01.19.2026 through 16:00 on 01.19.2026 .
        A GMD warning of K8 or greater is in effect for this period. 
        End time: 01.19.2026 16:00 
    
    (All times are prevailing Eastern US time)

    I've posted on this before, for other warnings. Not going to repeat that.

  • rediguanayum4 hours ago
    Moon should be good too to see Aurora tonight: waxing crescent 1% https://www.moongiant.com/phase/today/
  • drmpeg2 hours ago
    Although everyone is interested in visible aurora, the proton flux is also really impressive. It peaked at 37,000 pfu at 1910Z. The highest ever recorded was 43,500 pfu in March 1991.
  • bashtoni4 hours ago
    Australian Bureau of Meteorology advisory for visible aurora: https://www.sws.bom.gov.au/Aurora
    • jp0d4 hours ago
      Are there any resources to track Aurora sightings or predicted sightings?
      • lakid30 minutes ago
        https://aurora-alerts.uk/ Ignore the UK TLD, this tracks global sightings
      • stubish3 hours ago
        At the bottom right of that page is a subscribe link, with a number of different alerts and lists to subscribe to.
    • aussieguy12342 hours ago
      Worth noting that Kp, which many talk about in discussions online, is more or less useless for anyone in Australia or the southern hemisphere. Lots of beginner Aurora chasers here get tripped up by that.

      What is useful is KAus and the G index, KAus is shown on this page, so thats what i'll be tracking.

    • hahahahhaah4 hours ago
      Is that tonight or last night?
      • bashtoni3 hours ago
        It was only issued this morning Australian time, so I presume it's for tonight.
  • WhitneyLand3 hours ago
    How rare is this?

    G4 storms are ~100 per solar cycle (~11 years).

    So roughly 9 G4 events/year on average.

    • tbrownawa minute ago
      But they should mostly be in the same part of the cycle rather than spread evenly.

      It probably wouldn't make sense to calculate "average snow days per month" across an entire calendar year (in most places...), this is the same thing.

    • burnt-resistor2 hours ago
      Like 20-25 years rare according to some space weather youtuber.
  • nbf_19952 hours ago
    Title says "S4" solar radiation event, but the linked page says "G4" geomagnetic storm
  • dschuessler5 hours ago
    This page looks like an accessibility nightmare. The entire warning text is an image. There is no transcription present for screen reader users. I did not expect this from a government website.
  • Kunsang2 hours ago
    • neogodless36 minutes ago
      This is definitely not a language I speak!

      Flux and bZ!

  • ComputerGuru4 hours ago
    Do you need long exposure to make it visible with a camera? How does that work in the presence of light pollution?
    • thebruce87m4 hours ago
      Tonight I could see the colours without the camera but it definitely stands out more with the long exposure of the camera.

      Even with lights in the direct line of the shot you you can get good results - presumably the phone is doing HDR to achieve this.

    • Macha3 hours ago
      Local light pollution normally makes it hard to see with anything short of long exposure, but today it was naked eye visible and regular photos also captured it.
  • JoeDaDude2 hours ago
    There is a video update from the NOAA Space Weather Prediction Center. (I could only find this on Facebook) https://www.facebook.com/reel/1190509063198524
  • aliljet3 hours ago
    I wonder if we're going to see an aurora over Seattle tonight?
  • PlatoIsADisease4 hours ago
    Years ago I was concerned about this and made a plan with my wife for what to do if she was at work.

    But now we have a bunch of kids in different schools and haven't updated our plan.

    Does anyone have a plan for what happens if we have a really bad event?

    • hnuser1234564 hours ago
      A really bad event would be that long-distance transmission lines act like antennas and pick up millions of volts and blow up all the transformers.

      I don't know how much you can plan for that other than "if it happens, try to get home", and then all the usual prepper stuff.

    • myself2483 hours ago
      Pray for clear skies and go out and watch the beautiful aurora, silly!

      Depending on the kids' ages, you can teach them quite a lot about the Earth's magnetic field and why the aurora concentrates at the poles, how the high-energy particles light up the sky (it's a lot like a neon light), and how the atmosphere shields us from any danger despite the spectacular show.

    • rootusrootus3 hours ago
      For a really bad event that managed to blow a lot of transformers (presumably due to grid operators not seeing it coming) ... well, take up farming.
    • Tepix4 hours ago
      Buy a bit of extra food and water.
      • y1n03 hours ago
        And toilet paper! Rolls and rolls of toilet paper!
    • fuzzer3714 hours ago
      Keep a couple days water and food on hand, go up to the pub, have a pint, and wait for this all to blow over.
      • JoshTriplett4 hours ago
        With how much modern cars rely on electronics, I would not try to drive during such an event.
        • lxgr4 hours ago
          Solar flares are only dangerous to very long conductors.
        • whyleyc3 hours ago
          It’s ok - The Winchester is within walking distance.
          • jrgd2 hours ago
            Omg i watched this yesterday!
        • throwaway815232 hours ago
          That's a safety feature. It prevents you from drinking and driving if you go to a pub during a solar flare. :)
        • jrgd2 hours ago
          No one would drive to the pub anyway. Better walking back home…
          • JoshTriplett2 hours ago
            Valid. I think I have such an ingrained different set of assumptions (a pub being just another kind of place for food, and "going to" anything involving a form of transportation) that that didn't even occur to me.
    • swader9994 hours ago
      First rule of fight club...
  • tigerlily3 hours ago
    Hopefully it's clear space weather for Artemis II coming up. I wonder what they do if it's inclement en route?
    • perihelions3 hours ago
      There's not that much they can do. It's often discussed that if the extreme August 1972 solar storm had overlapped with an Apollo mission (it didn't), it would have acutely sickened the astronauts.

      https://en.wikipedia.org/wiki/August_1972_solar_storms#Human...

      > "Had a mission been taking place during August, those inside the Apollo command module would have been shielded from 90% of the incoming radiation. However, this reduced dose could still have caused acute radiation sickness if the astronauts were located outside the protective magnetic field of Earth, which was the case for much of a lunar mission. An astronaut engaged in EVA in orbit or on a moonwalk could have experienced severe radiation poisoning, or even absorbed a potentially lethal dose."

      The Orion capsule's contingency plan looks something like this:

      > "To protect themselves, astronauts will position themselves in the central part of the crew module largely reserved for storing items they’ll need during flight and create a shelter using the stowage bags on board. The method protects the crew by increasing mass directly surrounding them, and therefore making a denser environment that solar particles would have to travel through, while not adding mass to the crew module itself."

      https://www.nasa.gov/missions/artemis/orion/scientists-and-e...

  • _carbyau_4 hours ago
    Weirdly, while the site in question is "blaring klaxons!" there are more "cool night lights!" posts than concern.
    • zamadatix4 hours ago
      Unless you're in space, a large scale electrical operator, or relying on HF radio there isn't much reason to be interested other than the lights for a G4 (what this is currently classed as).
      • pvab323 minutes ago
        my Telecaster sure was noisy this morning but I didn't think much of it
    • rzzzt3 hours ago
    • guerrilla4 hours ago
      > while the site in question is "blaring klaxons!"

      No, it isn't. It clearly says everything is under control but it would be good to keep an eye on it.

  • aussieguy12344 hours ago
    I'll be going out tonight if this continues into Australian night time hours.

    At this strength, I could see the full display including colors with my naked eye in Melbourne, May 11th 2024. This storm is slightly stronger than that event.

  • uticus6 hours ago
    Possible aurora visible through central US tonight
  • zahlman4 hours ago
    It seems that the peak was several hours ago, and I haven't observed any effects from it...
    • guerrilla4 hours ago
      The peak was originally supposed to be 6-7 hours from now... it's still showing KP 8 here though, so I'm not sure what's going on. It could get more intense.
  • ferguess_k4 hours ago
    Darn Montreal is still too south. Wish I were in Winnipeg.
  • tramtrist3 hours ago
    We never get aurora in Japan :(
  • anon1152 hours ago
    any effects on the human body??
  • cbeach3 hours ago
    Probably a stupid question, but should I unplug my EV? (UK)
    • qayxc3 hours ago
      No need. Wrong type of solar event. You might be able to see auroras, though. I saw some a couple of hours ago.
    • jacquesm3 hours ago
      No.
  • burnt-resistor2 hours ago
    Up to G-5 possibly. Cell phone visible in dark areas throughout most of CONUS.

    It was mentioned that air travel ionizing radiation exposure increases during geomagnetic storms. I'd consider pausing travel for a couple of days to not be a guinea pig because there's not enough data to consider it safe. If anyone absolutely must fly tonight, it'd be interesting if they were to take a high sensitivity dosimeter to see what happens.

  • 7 hours ago
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  • yzydserd4 hours ago
    [flagged]