We don't yet know if this flare hurled a CME into space. If it did, it could have a grazing Earth-directed component. Confirmation awaits fresh data from SOHO coronagraphs.
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Giant sunspot AR3664 unleashed another X-flare today (May 11th @ 0139 UT)--its strongest yet. NASA's Solar Dynamics Observatory captured a bright ultravolet flash from the category X5.8 explosion: Radiation from the flare caused a deep shortwave radio blackout over the Pacific Ocean. Ham radio operators and mariners may have noticed loss of signal at frequencies below 30 MHz for as much as an hour after the flare's peak.
We don't yet know if this flare hurled a CME into space. If it did, it could have a grazing Earth-directed component. Confirmation awaits fresh data from SOHO coronagraphs. https://spaceweather.com/
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The first of six CMEs hurled toward Earth by giant sunspot AR3664 hit our planet's magnetic field today. The impact on May 10th at 1645 UT jolted magnetometers around the world and sparked a severe (G4-class) geomagnetic storm. This storm is underway now. More CMEs are following close behind and their arrival could extend the storm into the weekend. Sign up for Space Weather Alerts to receive instant text messages when the CMEs arrive. The ongoing storm is producing low-latitude auroras in the southern hemisphere. Ken James sends this picture from the Snake Valley Observatory in Victoria, Australia: "The red, yellow and green colours were easily visible to my naked eye," says James. Readers in the USA should note that the southern latitude of Victoria, Australia, 37 degrees, is the same as the northern latitude of central California. That's how far down auroras could be seen if it were dark instead of daylight in North America. Why is this storm so severe? Take a look at the solar wind data from NOAA's DSCOVR spacecraft: After the CME struck, the speed of the solar wind blowing around our planet abruptly increased to more than 700 km/s. More importantly, south-pointing magnetic fields from the sun washed over the Earth, opening a crack in our planet's magnetosphere. Solar wind poured through the gap to turbo-charge the storm.
https://spaceweather.com/ No. AR3664 is indeed a 'Carrington-class' sunspot, but the CMEs it hurled toward Earth over the past few days are not as potent as the monster CME of Sept. 1, 1859. NOAA says we might experience a severe geomagnetic storm when the CMEs arrive this weekend. If geomagnetic storms were hurricanes, 'severe' would be category 4. The Carrington Event was category 5 or greater. So this is no Carrington Event. Even so, category 4 is pretty intense--if it happens. Stay tuned for some great auroras!
Great sunspot AR3664 has hurled an astonishing five CMEs toward Earth. They're all in this frenetic 2-day coronagraph movie from the Solar and Heliospheric Observatory (SOHO): The two bright objects are Jupiter (left) and Venus (right). The CMEs will miss those planets and hit Earth instead.
According to a NOAA forecast model, the first three CMEs could merge for form a "Cannibal CME." Cannibal CMEs form when fast-moving CMEs overtake and gobble up slower CMEs in front of them. Internal shock waves created by such CME collisions do an good job sparking geomagnetic storms when they strike Earth's magnetic field. The Cannibal CME is expected to arrive on May 11th. It alone could spark a strong (G3) geomagnetic storm. With two more CMEs following close behind, storm levels could become extreme (G4), sparking auroras at mid- to low-latitudes across Europe and the USA. https://spaceweather.com/ Sunspot AR3615, last seen in March crackling with X-flares, is now transiting the farside of the sun. The sunspot is so big, it is affecting the way the sun vibrates, allowing researchers to detect its seismic echo. Also, NASA's rover Perseverance can see the sunspot all the way from Mars. This large active region will return to the Earthside of the sun about a week from now.
https://spaceweather.com/ Big sunspot AR3590 is as dangerous as it looks. Late yesterday (Feb. 21 @ 2307 UT), the active region produced a powerful X1.8-class solar flare with a shortwave radio blackout over the western USA and Pacific Ocean. NASA's Solar Dynamics Observatory recorded the extreme ultraviolet flash: Hours later (Feb. 22 @ 0635), the sunspot erupted again, producing an almost identical X1.7-class flare. Neither explosion produced a bright CME. This means the double flares will *not* cause a geomagnetic storm on Earth.
More explosions are in the offing. AR3590 has an unstable 'beta-gamma-delta' magnetic field that harbors energy for additional X-class explosions. https://spaceweather.com For the second time in less than a week, energetic solar protons are raining down on Earth's upper atmosphere. Forecasters call this a "solar radiation storm." Today's storm (near category S2) is rich in "hard protons" wiith energies greater than 50 MeV. It is causing a shortwave radio blackout inside the Arctic Circle and speckling the cameras of some Earth-orbiting satellites. The plot above shows storm data recorded by NOAA's GOES-18 satellite in Earth orbit. Sensors on the satellite are counting energetic protons as they pass by en route to Earth. Triggered by an explosion near the sun's southwestern limb (inset), this storm could last for another 24 hours.
https://spaceweather.com/ Yesterday (9 February) at 13.14 UT, the sun produced one of the most powerful solar flares in years, an X3.4-class explosion from just behind the sun's southwestern limb. NASA's Solar Dynamics Observatory (SDO) recorded the extreme ultraviolet flash: The source of the flare appears to be departing sunspot AR3575. Because the blast site was eclipsed by the edge of the sun, the flare was probably even stronger than its X3.4 classification suggests. This was a big explosion. Hours after the flare's peak, Earth was still feeling the effects of the blast. Solar protons energized by the flare are following curved magnetic field lines from the sunspot back to our planet. The resulting hailstorm, called a "radiation storm," is still intensifying at the time of this writing (9 February) and has just reached category S2: This plot shows what NOAA's GOES-18 satellite is seeing right now. The colored lines count the number of energetic protons streaming past the satellite en route to Earth. Green and blue are of special interest because they trace "hard protons" capable of upsetting spacecraft electronics, e.g., causing reboots of onboard computers and temporarily fogging cameras. The explosion also hurled a bright CME into space. It will not hit Earth. Instead, a NASA model of the CME shows it is heading for Mercury, Venus and Mars. It will hit all three planets this weekend. 10 February 2024: For the second day in a row, energetic protons from the sun are raining down on Earth. This is called a "solar radiation storm," and it is currently a category S2 event. A data-plot from NOAA's GOES-18 satellite shows how protons surged around our planet just after yesterday's X-class solar flare: The colored lines count the number of energetic protons streaming past GOES-18 en route to Earth. Green and blue are of special interest because they trace "hard protons" capable of upsetting spacecraft electronics, e.g., causing reboots of onboard computers. These particles can even reach all the way down to aviation altitudes, boosting dose rates for passengers and crews flying commercial planes over Earth's polar regions. We can actually *see* some of these protons. Take a look at this SOHO coronagraph movie of the sun hours after the flare: The "snow" in this movie is caused by the radiation storm. Each speckle is a solar proton striking the spacecraft's digital camera. This is a good example of how radiation storms can temporarily interfere with orbital imaging systems.
Another effect of the radiation storm is an ongoing blackout of shortwave radio transmissions around Earth's poles. This is called a "polar cap absorption event". Earth's magnetic field is guiding many of the incoming protons towards the poles, where they ionize the upper atmosphere; this, in turn, wipes out radio signals below 30 MHz. Many shortwave radios inside the Arctic Circle simply won't work until the radiation storm is over. https://spaceweather.com For the second month in a row, sunspot counts in the sun's northern hemisphere are more than double the south. The asymetry is obvious in this summary of September's sunspots compiled by astronomer Senol Sanli using data from NASA's Solar Dynamics Observatory: According to the Royal Observatory of Belgium's Solar Influences Data Analysis Center, in September the monthly sunspot number for the sun's northern hemisphere was 90, the southern hemisphere was only 44; that's a ratio of 2-to-1 in favor of the north. August was about the same. Looking back over an entire year, the north is leading the south by an average of 50%. What's going on? In fact, it's not unusual for the sun's northern and southern hemispheres to be out of synch. As long ago as the 19th century, solar cycle pioneers Spoerer (1889) and Maunder (1890) noted that there were often long periods of time when most sunspots were found preferentially in one hemisphere and not the other. This plot from the Royal Observatory of Belgium shows assymetries throughout the last 6 solar cycles: Until recently, Solar Cycle 25 was pretty evenly matched, north vs. south. Sunspot counts from August and September, however, suggest that the northern hemisphere may be seizing control--at least temporarily. This has happened during the upslope of all four previous solar cycles (21-24).
One possible explanation for this phenomenon may be that the two hemispheres of the sun have their own solar cycles, one out of phase with the other by about a year. Indeed, Solar Max is often double peaked. You can see it in the hemispheric sunspot plot. In the three most recent cycles (22-24), north peaked before south, creating two surges of solar activity separated by a "Gnevyshev gap." Solar Cycle 25 might continue this trend. A complete discussion of sunspot asymmetries is included in David Hathaway's excellent review article "The Solar Cycle." https://spaceweather.com/ The sun is partying like it's 2002. That's the last time sunspot counts were as high as they are now. The monthly average sunspot number for June 2023 was 163, according to the Royal Observatory of Belgium's Solar Influences Data Analysis Center. This eclipses every month since Sept. 2002: Above: This plot is based on NOAA's interactive Solar Cycle Progression. Check it out! Solar Cycle 25 wasn't expected to be this strong. When it began in Dec. 2019, forecasters believed it would be a weak cycle akin to its immediate predecessor Solar Cycle 24. If that forecast had panned out, Solar Cycle 25 would be one of the weakest solar cycles in a century.
Instead, Solar Cycle 25 has shot past Solar Cycle 24 and may be on pace to rival some of the stronger cycles of the 20th century. The last time sunspot numbers were this high, the sun was on the verge of launching the Great Halloween Storms of 2003, which included the strongest X-ray solar flare ever recorded (X45), auroras as far south as Texas, and a CME so powerful it was ultimately detected by the Voyager spacecraft at the edge of the solar system. www.spaceweather.com March was another strong month for Solar Cycle 25. According to NOAA, the average sunspot number was among the highest of the past 10 years: Originally, forecasters thought Solar Cycle 25 would be about the same as Solar Cycle 24, one of the weakest solar cycles in a century. March's sunspot numbers are the latest sign that Solar Cycle 25 will exceed predictions. In fact, Solar Cycle 25 has outperformed the official forecast for more than 24 months in a row.
Solar Maximum is not expected until 2024 or 2025, so the solar cycle has plenty of time to strengthen, bringing more X-flares, geomagnetic storms and auroras. You can follow the progression here. https://spaceweather.com/ Something rare and strange happened last month. On Feb. 23rd, growing sunspot AR3234 produced an M-class solar flare. It was nearly midnight in Florida when the explosion occurred, so you'd expect no one there to notice. On the contrary, in the community of High Springs, FL, amateur radio astronomer Dave Typinski recorded a strong shortwave radio burst. "You CAN see the sun at midnight in Florida... sometimes," says Typinski. This is what his instruments recorded while the flare was underway: A double wave of static washed over Florida, filling the radio spectrum with noise at all frequencies below 25 MHz. "The Sun was 69° below the horizon when this happened," he marvels. How is this possible? The entire body of our planet was blocking the event from Typinski's antenna. It's called "antipodal focusing". First postulated by Marconi more than 100 years ago, antipodal focusing is a mode of radio propagation in which a signal starts out on one side of the planet, gets trapped between Earth's surface and the ionosphere, and travels to the opposite hemisphere. Waves converging at the antipode can create a surprisingly strong signal. "This is the second or maybe third midnight solar radio burst I've seen in ten years, but it's by far the strongest," says Typinski. "The previous events happened at the height of Solar Cycle 24. They're quite rare." This diagram from a declassified US Gov.report shows the basic geometry of antipodal focusing. Pause: Yes, solar flares can produce radio signals. Typinski's midnight burst was a "Type V", caused by streams of electrons shooting through the sun's atmosphere in the aftermath of the flare. Plasma waves rippling away from the streams emited intense bursts of natural radio static. The burst was first observed in broad daylight at the Learmonth Solar Observatory in Australia, then it curved around Earth to reach Typinski. Above: An example of antipodal focusing of seismic waves caused by the Chicxulub asteroid impact. The geometry is the same as for radio waves. [more]. "This propagation mode was used during the Cold War," notes Typinski. "The U.S. would park a SIGINT ship in the south Pacific to grab signals from the Eastern Bloc. The Soviets probably did the same thing, parking in the southern Indian ocean."
Turns out, this method of spying works for radio astronomers, too. Would you like to record an event like this? NASA's Radio JOVE program makes it easy. Off-the-shelf radio telescope kits allow even novices to monitor radio outbursts from the sun, which are becoming more frequent as Solar Cycle 25 intensifies. www.spaceweather.com It seemed like sunspot AR3088 would never stop exploding. Over the past four days, the strangely-magnetized active region produced more than a dozen M-class solar flares: Each X-ray peak in the graph above produced a corresponding shortwave radio blackout on Earth. No part of our planet was untouched. More than half of the explosions also produced a coronal mass ejection (CME). Earth dodged them all. Only one and maybe two delivered glancing blows of no consequence. All the rest sailed harmlessly into space. The simple reason why: AR3088 was never facing Earth. Most of the explosions occurred while the sunspot was approaching or even rounding the sun's western limb. This movie from NASA's Solar Dynamics Observatory is a good example. It shows a flare from AR3088 on Aug. 29th partially eclipsed by the edge of the sun. The explosion registered M9 on GOES satellite X-ray sensors, but the uneclipsed flare was probably much stronger--perhaps even an X-flare.
If the sunspot had been facing us, we might now be experiencing strong geomagnetic storms with spectacular low-latitude auroras. Maybe next time... https://spaceweather.com/ Solar Cycle 25 continues to overperform. Sunspot counts for Sept. 2021 were the highest in more than 5 years. And, for the 11th month in a row, the sunspot number has significantly exceeded the official forecast. The plot above shows sunspot counts vs. time. The red curve traces the forecast issued by the NOAA/NASA Solar Cycle 25 Prediction Panel in 2019. It calls for a relatively weak solar cycle peaking in July 2025. The sun has a mind of its own, though. Higher-than-expected sunspot counts suggest a stronger cycle, with a peak occurring in late 2024 instead of mid-2025. This is good news for aurora watchers, but maybe not so good for the Internet. https://spaceweather.com/ Suspicious0bservers: Daily Sun, Earth and Science News
Today's Featured Links: Slime Mold, Cosmic Web? - https://news.ucsc.edu/2020/03/cosmic-... - https://arxiv.org/pdf/2003.04393.pdf New Moon Hypothesis Need: https://news.unm.edu/news/new-researc... Solar Forecast: https://arxiv.org/pdf/2003.04563.pdf Geomag Max in Mesopotamia: https://www.sciencedirect.com/science... Amazon to Disappear? https://www.bangor.ac.uk/news/researc... … Probably not: https://earthobservatory.nasa.gov/ima... |
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