NOAA has issued a rare G4 watch for a severe geomagnetic storm that is expected on October 10 and 11. G4 refers to NOAA's scale for the intensity of geomagnetic storms, which ranges from G1 to G5. Prior to the geomagnetic storm in May of this year that reached G5 intensity, the last G4 watch was issued in January of 2005.
This watch was issued for a coronal mass ejection (CME) that occurred around 03 UTC on October 9 and is expected to reach Earth around 12-15 UTC on October 10. An article from the Washington Post states that the speed of the CME, around 2.5 million miles per hour, is the fastest that a CME has been ejected toward Earth during the current solar cycle. From my very limited understanding of space weather, it seems that faster CMEs generate higher ram pressures against Earth's magnetosphere and can result in more severe geomagnetic storms. The x-ray brightness of solar flares gets a lot of attention, and this was an X-class flare (the highest level on the classification scale), this was an X1.8 flare whereas flares have been observed at least up to X28. The high speed of the CME, however, seems to be a factor in the potential for a severe geomagnetic storm.
One of the main questions that we can't answer until the CME gets to within about a million miles of Earth is the orientation of its magnetic field. If the CME's magnetic field is aligned in the same direction as Earth's, it will produce a less severe geomagnetic storm than if it's aligned in the opposite direction. An excellent resource for data about space weather and this CME is NOAA's space weather enthusiasts dashboard. There's a lot of data on that page that is useful if you're concerned about the possibility of viewing auroras or potential disruptions to the power grid, so hopefully some of the comments can explain a bit more about what it means. I don't know a whole lot about space weather, but I'll try to offer a cursory explanation of what I believe some of it means.
The solar visible light shows where sunspots are currently observed, whereas the LASCO C3 images are observed from satellites can be used to see CMEs when they occur. A CME will appear like an explosion outward from the sun's corona. The data is input into a model called WSA-ENLIL, which predicts the density and radial velocity (outward from the sun) of solar wind plasma. A higher plasma density or a faster radial velocity should result in a stronger geomagnetic storm. This is also useful for estimating when a CME will reach Earth. I believe the GOES magnetometer data is used to measure how much the Earth's magnetic field is compressed or stretched and can identify the onset of geomagnetic storms. The ACE MAG and SWEPAM data are satellite-derived measurements of the solar wind. In addition to showing the plasma speed, temperature, and density, the Bz and Phi variables show the orientation of the magnetic field in the solar wind. If Bz is positive, it's a northward-oriented magnetic field. However, a negative Bz indicates a southward-oriented magnetic field, the opposite direction of Earth's magnetic field, and this can result in more severe geomagnetic storms. Basically, a strongly negative Bz around -10 or even -20 would be more favorable for a strong geomagnetic storm. The aurora forecast is a short-term forecast (~30 minutes to an hour) of the probability of auroral activity over a location, though auroras may be visible near the horizon in areas equatorward of what the forecast shows.
There's a lot of data on NOAA's space weather dashboard that can be useful for anyone hoping to see the auroras. My understanding of space weather is very limited, so if anyone else has a better understanding of what the data means, please share the information in the comments. Although a G4 or even a G5 geomagnetic storm is possible, but there's still a lot of uncertainty until the CME gets very close to Earth.
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Three of our community had sent in submissions regarding the solar storms expected to arrive over the weekend. Auroras, weather permitting, will be visible over much of the northern hemisphere. For those of you who like to see such things, or for those of you looking for something different to do, why not get outside and take a look:
Updated flare status
For the first time since October 2003, G5 conditions have been observed. This is described as an extreme geomagnetic storm and is the highest level on NOAA's scale for geomagnetic storms. In addition to reaching G5 conditions, an S2-level solar radiation storm was observed today, and HF radio blackouts at the R3-level have occurred multiple times.
If you're hoping to see auroras, NOAA provides real-time short-range ~30-60 minute forecasts of auroral activity in both the northern and southern hemispheres. There is also a separate dashboard for monitoring disruptions to HF radio.
Solar storms incoming this weekend
Earth prepares for solar storm impact from three CMEs this weekend
Solar activity has reached high levels in the past 24-36 hours, with background flux at or near M1.0. The most significant developments from the Sun include the growth and merging of Regions 3664 and 3668, as well as the production of numerous M-class solar flares and two X-class solar flares from CMEs that are expected to arrive at Earth this weekend.
Sunspot AR3663 released five plumes of solar plasma—coronal mass ejections, or CMEs—in the past day, with the second, third, and fifth being forecast to slam directly into our planet this weekend.
This could lead to "strong" geomagnetic storms in our magnetic field and atmosphere, which could result in auroras being seen as far south as Illinois and Oregon.
(Score: 3, Informative) by day of the dalek on Thursday October 10 2024, @08:06AM (1 child)
The space weather enthusiasts dashboard [noaa.gov] shows coronagraph images from the SOHO satellite. As I said in the summary, this is typically for detecting CMEs as they're being ejected out from the sun's corona. But there's a bright white streak across the upper-right quadrant of the image right now, too. It's not caused by the sun's corona, nor is it a fault with the satellite's instruments. That's actually comet Tsuchinshan-Atlas crossing the satellite's field of view [noaa.gov].
Currently living rent free in aristarchus' head. [soylentnews.org]
(Score: 2) by Reziac on Friday October 11 2024, @03:37AM
Another view you can move around:
https://classic.nullschool.net/#current/space/surface/level/anim=off/overlay=aurora/orthographic=283.38,-5.15,579/loc=-102.097,33.543 [nullschool.net]
And there is no Alkibiades to come back and save us from ourselves.
(Score: 2, Informative) by Anonymous Coward on Thursday October 10 2024, @10:20AM (1 child)
That the Orange Shitstain wants to shut down an privatize NOAA
(Score: 1, Funny) by Anonymous Coward on Thursday October 10 2024, @03:42PM
Sir, you have insulted my underwear drawer for the last time. I demand satisfaction! Tighty-whities at 10 paces at the crack of noon!
(Score: 4, Insightful) by VLM on Thursday October 10 2024, @12:03PM (3 children)
The best link I can think of for web SDRs would be
http://kiwisdr.com/public/ [kiwisdr.com]
There are probably better lists.
Note that the value of radio monitoring increases with experience; where I live its "normal" to hear 5 MHz WWV but not 10 MHz at this time of day. That will change after sunrise. Normally I'll hear "pretty good" 10 MHz WWV all day. I'll try to check in between my other activities it'll be interesting to see how disrupted it gets. My point being that if I had a SDR on that list if someone who never used it tuned in either yesterday or today or tomorrow they'd be able to draw roughly zero useful conclusions from whatever they observe, but I've occasionally tuned in WWV since the 80s so I have a pretty good idea of normal vs abnormal radio propagation patterns so I probably could draw a useful conclusion based on observations.
Note that this storm is large but not unusually so.
This plays into the gradual and seemingly permanent de-technical-ization of the internet. In the old days, if there was anything about the USGS Boulder CO magnetometer, it would have been a FTP site with raw data going back 25 years. Sadly, there is a general trend on the internet to remove historical data and replace it with (often AI generated swill) journalism articles. So you can find elementary school classroom presentations on the Boulder magnetometer, but you'll find it near impossible to find actual data. Sort of like the de-technicalization of NASA, where you used to be able to "easily" find raw data files from space probes but that's all buried under journalism and pretty pictures and the occasional predictions, fearmongering and otherwise. However the point of this rant is if you COULD find a list of recent historical geomagnetic conditions you'd see G4 is pretty common. Like "more often than I get a thunderstorm" common where I live. I THINK the story is they're hedging their bets that this might be much larger like a major G5. That would indeed be interesting. However if you try to search for the Boulder magnetometer you'll get perhaps 100 to 200 boosterism journalism articles which provide roughly zero value, unfortunately. I would have liked to post a list of the geomagnetic conditions over the past month and also a short list of the last 5 or so G4 storms to give some context, but the internet is non-technical now, propaganda and boosterism only. Kind of sucks.
The internet used to be technical, then it was "for pr0n", now its propaganda and filler material (often AI generated) almost exclusively.
(Score: 1) by day of the dalek on Thursday October 10 2024, @12:54PM (2 children)
The NOAA scale for geomagnetic storms is directly linked to the planetary K index, sometimes referred to as the Kp index. Historical data for this certainly is available online. If you'd like a plot of the frequency of three-hourly Kp index values in each year, you can get those at https://kp.gfz-potsdam.de/en/figures/kp-values-frequency [gfz-potsdam.de]. If you'd like the raw data in a text file, that's also available at https://kp.gfz-potsdam.de/app/files/Kp_ap_since_1932.txt [gfz-potsdam.de]. The data set goes all the way back to 1932. Historically, a Kp index of at least 8- (7.667) was reached in a lot of years, but such occurrences have been a lot less frequent after 2005.
NOAA's forecast from yesterday evening said, "G4 (Severe) levels is likely with G5 (Extreme) levels possible." This morning's forecast still predicts a maximum Kp index of 8+, but still says that G5 conditions are possible. For what it's worth, although G4 conditions haven't occurred all that frequently since 2005, they've still happened several times, but prior to May of this year, NOAA hadn't issued a G4 watch since 2005. Here's an interesting article from earlier this year: https://www.nytimes.com/2024/06/25/science/mike-bettwy-solar-flares-storms.html [nytimes.com].
I don't fully understand why alerts are set up that way, but it seems like a G4 watch is the maximum that the Space Weather Prediction Center can issue.
Currently living rent free in aristarchus' head. [soylentnews.org]
(Score: 2) by VLM on Thursday October 10 2024, @01:23PM (1 child)
Yeah that's my point, I'd like to agree with you but your link is just a picture.
https://kp.gfz-potsdam.de/en/data#c222 [gfz-potsdam.de]
Is probably the best (maybe only?) source of data out there.
My general cantankerousness is related to there being hundreds of clickbait and filler articles in web searches hiding actual data like this.
(Score: 2, Informative) by day of the dalek on Thursday October 10 2024, @01:51PM
NOAA actually does have the data online, too. You'll just need to use FTP to download it. The URL is ftp://ftp.ngdc.noaa.gov/STP/GEOMAGNETIC_DATA/INDICES/KP_AP [noaa.gov].
I generally agree about a lot of articles being of low quality, and generative AI is certainly making things worse. Search engines are also to blame for providing lower quality results. For example, there have been many times where I'll search for the exact title of a journal article, and Google will return links to other articles from the same journal but not a link to the specific article I'm searching for. But despite the difficulty in finding data sometimes, it's my experience that NOAA really does make a very large amount of data freely available online.
For space weather observations, go to https://www.swpc.noaa.gov/observations [noaa.gov], click on any products, and then click on the data tab. It will have links to how to get raw and archived data. I've worked with weather and climate data sets, and there's a huge amount of observational and forecast data archived. Some of the really large data sets produced by NOAA like radar data and some raw data from the really high resolution forecast models are hosted by Amazon, but they can be easily searched and downloaded for free. The problem isn't that the data is unavailable, but it can be hard to find where to get some of the data from. I have no experience working with raw data from NASA, but I've generally had a pretty good experience getting data from NOAA. It's definitely become a lot easier in the past several years to get raw weather radar data, and that's a massive data set that goes back as far as the early 1990s for some radars.
I won't defend the clickbait or poor search engine results, but I think NOAA actually does a pretty good job of making their data available to the public.
Currently living rent free in aristarchus' head. [soylentnews.org]
(Score: 2) by VLM on Thursday October 10 2024, @06:46PM (1 child)
At 1830 UTC I see the Kp value is supposed to be 8, and the forecast was its going to get "about two points worse than whatever it is at 1800" so that's kind of bad.
On the other hand I'm listening to WWV on 10 MHz and the skywave does not sound any wierder than it ever does. Maybe its not having an impact yet or not enough of a SNR degradation for me to notice yet.
(Score: 2) by VLM on Friday October 11 2024, @01:11PM
Kp remains around 8 and WWV sounds about normal. Kind of a nothingburger
(Score: 3, Informative) by pTamok on Thursday October 10 2024, @09:34PM (2 children)
I'm seeing some spectacular Northern Lights. Green and red.
Of course, I don't have my best camera with me, or a tripod. I still have a couple of memorable shots though.
The skyglow where I usually am drowns stuff out, but they have been incredibly bright - when I first saw them, I thought it was the Moon behind high cloud.
(Score: 1, Informative) by Anonymous Coward on Friday October 11 2024, @02:28PM
Similar reports from friends along the Maine shoreline (in a fairly dark-sky area). They've sent a couple of fabulous aurora photos.
(Score: 0) by Anonymous Coward on Friday October 11 2024, @11:28PM
Randall Munroe saw some too--
https://xkcd.com/2997/ [xkcd.com]
(Score: 2) by corey on Thursday October 10 2024, @10:22PM
The Bureau of Meteorology SWS website is good to keep an eye on. I am on their mailing list and they issued a couple of warnings yesterday. But unfortunately I’m on holiday in Queensland where it’s tropical, strong and rainy (plus fairly bad light pollution), so I’m not going to see anything.
https://www.sws.bom.gov.au/Space_Weather [bom.gov.au]