Sun activity for December 4, 2023: Waiting on the solar wind!
Today’s top news: Aurora watchers get ready. The solar wind stream is on its way. The giant coronal hole continues to spew out lots of fast solar wind toward Earth. The speed of the solar wind at Earth has started to slowly increase but so far the full stream of solar stuff is not yet blasting Earth’s magnetic field. The stream is expected to reach us by midday UTC today (December 4). It’s expected to cause a G2 (moderate) geomagnetic storm. The rush of solar particles should continue into the next day (December 5) with slightly calmer storms at the G1 (minor) level. Please submit your images to EarthSky’s community page.
Last 24 hours: Sun activity is low with 15 C flares over the observation period (11 UTC yesterday to 11 UTC today). The large event was a C8.1 flare from AR3511 at 1:22 UTC December 4. AR3500 produced the most flares during the period at three flares. The sun has eight active regions on its Earth-facing side.
Next 24 hours: Today’s forecast is a 99% chance for C flares, a 30% chance for M flares, and a 5% chance for X flares.
Next expected CME: No Earth-directed coronal mass ejections (CMEs) were observed in the available imagery.
Current geomagnetic activity: Earth’s geomagnetic field is unsettled at the time of this writing (11 UTC on December 4). The large coronal hole on the Earth-facing side of our star is now located in a geoeffective position, a position where its high-speed solar wind will impact Earth’s magnetic field. The solar wind is expected to impact Earth midday today, December 4 (UTC). G2 (moderate) geomagnetic storming is forecast for today with G1 (minor) storms on December 5. In the words of Jim Morrison of The Doors, we are “waiting for the sun”. And more aurora is on the way!

Sun activity for December 3, 2023: Giant coronal hole spraying Earth!
EarthSky sun activity author Dr. C. Alex Young also produces @thesuntoday.
Today’s top news: A large coronal hole spewing out lots of fast solar wind has rotated into a geoeffective position, that is, a prime position for affecting Earth. So that stream of solar stuff is due to blast Earth’s magnetic field, meaning more geomagnetic storms … meaning more auroras! The stream is expected to reach us by midday UTC tomorrow (December 4). It’s expected to cause a G2 (moderate) geomagnetic storm . The rush of solar particles should continue into the next day (December 5) with slightly calmer storms at the G1 (minor) level. Aurora watchers get your warm clothes and cameras ready, and please submit your image to EarthSky’s community page.
Last 24 hours: Sun activity is low with 12 C flares over the observation period (11 UTC yesterday to 11 UTC today). The large event was a C4.0 flare from AR3499 at 7:54 UTC December 3. AR3500 produced the most flares during the period at five C flares. The sun has six active regions on its Earth-facing side.
Next 24 hours: Today’s forecast is a 99% chance for C flares, a 35% chance for M flares, and a 10% chance for X flares.
Next expected CME: The coronal mass ejection (CME) produced during the M1.0 event by AR3500 (at 21:20 UTC on December 1) is expected to graze Earth on December 5. No other Earth-directed coronal mass ejections (CMEs) were observed in the available imagery.
Current geomagnetic activity: Earth’s geomagnetic field is unsettled at the time of this writing (11 UTC on December 3). It’s expected to continue at quiet-to-unsettled levels during the rest of December 3. The large coronal hole on the Earth-facing side of our star is now located in a geoeffective position, a position where its high-speed solar wind will impact Earth’s magnetic field. The solar wind is expected to impact Earth midday December 4 (UTC). G2 (moderate) geomagnetic storming is forecast for December 4 with G1 (minor) storms on December 5. More aurora is on the way!

Sun activity for December 2, 2023: Fantastic auroras, over past day
Today’s top news: What a day for auroras! As of this writing (11 UTC on December 1), there have been reports of beautiful displays across many time zones and from Earth’s northernmost and southernmost regions. The excitement lasted all day on December 1 as night fell around the globe. For most of the day, Earth’s magnetic field was engaged in G1 (minor) storming. There were also peaks of G2 (moderate) and up to G3 (strong) at around 11 UTC yesterday. Here in the Northern Hemisphere, auroras were reported as far south as northern California – and even Arizona – in the U.S. And Scandinavia reported auroras as far south as Oslo. Iceland had auroras, of course, and also Australia! Thank you all for the beautiful photos you shared at our community page. Keep ’em coming! Earth’s geomagnetic field is back to quiet this morning. It’s expected to continue at quiet-to-unsettled levels during the rest of the day through tomorrow as the effects of several coronal mass ejections (CMEs) on Earth’s magnetic field begin to wane. But more is coming. See Current Geomagnetic Activity below.
Last 24 hours: Turning our heads sunward, activity on our star continues at moderate levels. Sunspot group AR3500 once blasted out an M1.0 flare (at 21:20 UTC on December 1). It caused an R1 (minor) radio blackout on Earth, affecting an area over the South Pacific Ocean, east of French Polynesia. Strong activity has been observed over the past day on the sun’s northwest limb (edge), as long-lasting prominences flickered around the edges of our star. The northeast also showed activity with prominences and jets. In terms of flaring – compared to yesterday’s 14 C flares – we saw a small increase. In the past day, the sun produced 18 Cs, plus the abovementioned M, for a total of 19 flares. Sunspot group AR3500 continues as lead flare producer of the day (and the week). It blasted out 10 flares, the M included, out of the 19 of the past day. It’s also still the biggest sunspot region in extension on the Earth-facing sun. This region is fast moving to the sun’s southwest limb, carried by the sun’s rotation. It’ll be out of sight in the next couple of days. The sun today bears eight total active regions on its Earth-facing side.


Sun activity for December 1, 2023: G3 storm is here! Auroras started
Today’s top news: The excitement has begun, and there could be a lot more to follow! By monitoring the solar wind, we’ve been tracking the four coronal mass ejections (CMEs) that have been crossing the distance to Earth, and they’ve just arrived. The first first arrived late yesterday, causing a G1 (minor) geomagnetic storm. The second, a large combination of the three most recent CMEs, arrived just a few hours ago at the time of writing (11 UTC on December 1). A G2 (moderate) geomagnetic storm followed, soon jumping up to a G3 (strong) storm. Auroral imagery has already started flowing in online, largely thanks to graduate student and aurora hunter extraordinaire, Vincent Ledvina. Alaska and western Canada are enjoying the beginnings right now, but if the storm lasts until tonight, those in the northern US could have a show too. Stay tuned!
Last 24 hours: While we’re seeing exciting activity on Earth, sun activity is moderate after the production of one M flare between 11 UTC yesterday and 11 UTC today. The M1.1 was fired by sunspot group AR3502 at 4:39 UTC on December 1. The eruption caused an R1 (minor) radio blackout on Earth, affecting an area over the west coast of Australia. Besides the M, the sun produced 14 C flares during the past day. The lead flare producer of the day (and the week) is sunspot group AR3500, which threw out seven C flares. While showing some decay, this active region has kept its beta-gamma magnetic complexity, so the possibility of large M flares remains. It is still the largest and most complex of the ten active regions currently on the Earth-facing side of our star.
Sun activity for November 30, 2023: 4 blobs of sun coming our way
EarthSky sun activity author Dr. C. Alex Young also produces @thesuntoday.
Auroras incoming late tonight and tomorrow night! Four coronal mass ejections (CMEs) are currently headed toward Earth. These blobs of solar plasma and magnetic fields are expected to reach us late today into tomorrow. The first one (late today) will give the south of Earth a glancing blow. And then comes the big punch. Three CMEs should reach us early tomorrow, December 1. In fact – on its journey through space – a large CME that left the sun on November 28 will overtake the two events from the previous day, creating a complicated mass of sun-stuff known as a cannibal CME. Sound scary? Not at all. And it’s going to bring some beautiful auroral displays to northern latitudes! Forecasters are predicting up to a G3 (strong) geomagnetic storm, with auroras that could even be somewhat visible on the horizon to those at latitudes like those in the northern U.S. Good luck, aurora chasers!
Last 24 hours: Sun activity is back to low, with 14 C flares produced between 11 UTC yesterday and 11 UTC today. The largest was a C3.8 flare from sunspot group AR3500 at 14:35 UTC on November 29. This region has remained active after Tuesday’s almost-X flare, firing more flares than any other sunspot group (six out of the 14) as well as producing jets all day. It has kept its beta-gamma magnetic complexity, so the possibility of large M flares remains. It is the largest and most complex of the ten active regions currently on the Earth-viewed side of our sun.
Sun activity for November 29, 2023: Almost-X flare! Auroras incoming
EarthSky sun activity author Dr. C. Alex Young also produces @thesuntoday.
Bam! The sun almost reached X flare levels with an M9.8 released at 19:50 UTC on November 28. An X flare is the strongest category of solar flare. This almost-X came from sunspot region AR3500 near the center of the sun’s disk. It sent a CME (coronal mass ejection) straight toward Earth. Space weather forecasters at NOAA predict this blob of sun-stuff will reach Earth on November 30. This CME is traveling to us behind another CME – released from the sun on November 27 – which is expected to reach us on late November 29. Together, these two solar blasts may provoke G1 (minor) to G2 (moderate) geomagnetic storms at Earth. That means substantial auroras will be visible at higher latitudes. Fingers crossed for clear skies!
Last 24 hours: Sun activity has risen to high after the production of the M9.8 flare. Between 11 UTC yesterday and 11 UTC today, the sun released two M flares and six Cs. The M9.8 came shortly after an M3.4 at 19:13 UTC, November 28. Both flares came from AR3500, and both produced radio blackouts off the west coast of South America. The M3.4’s blackout was rated at R1 (minor), while the almost-X flare produced an R2 (moderate) blackout. AR3500 continues to show a beta-gamma magnetic complexity. The sun currently has ten active regions on its Earth-facing side.
Sun activity for November 28, 2023: More sun-stuff headed toward Earth
EarthSky sun activity author Dr. C. Alex Young also produces @thesuntoday.
The sun is at it again! We saw a huge eruption on the sun yesterday, and it’s headed our way. In fact, the last 24 hours was full of action, with a huge solar burp in the northeast at around 18:24 UTC yesterday, followed by another one slightly further northeast at around 22:23 UTC. And if those two weren’t enough, another blast came from an area not yet in view, just over the northeast limb (edge). The first two more than likely were directed toward Earth, while the third one will probably pass us by. As with the previous day’s eruption, if these coronal mass ejections (CMEs) are heading toward Earth, this could mean geomagnetic storms. And when Earth’s magnetic field gets disturbed, that means more auroras! Keep an eye out over the next few days.
Last 24 hours: With eight C flares produced by the sun during the past day, sun activity is currently deemed to be low. The largest flare was a C6.7 from AR3500 at 18:52 UTC on November 27. The lead flare producer of the period (11 UTC yesterday to 11 UTC today) is an unnumbered active region coming into view on the northeast limb, which fired two of the eight blasts. The sun currently has 10 active regions on its Earth-facing side. Sunspot group AR3500’s magnetic complexity reduced to a less-potent beta-gamma configuration, the same as AR3499. The rest of the active regions show simple alpha and beta configurations.
Sun activity for November 27, 2023: Watch sun-stuff blast into space
EarthSky sun activity author Dr. C. Alex Young also produces @thesuntoday.
It is a low sun activity day, but nobody told our star that. It released a huge rope of plasma and magnetic fields, a filament, off into space, possibly heading our way. We await further analysis for confirmation of an Earth-directed coronal mass ejection (CME). If this CME is heading toward Earth, this could mean disturbances in Earth’s magnetic field – aka geomagnetic storms – and that would mean more auroras. Stay tuned!
Last 24 hours: Sun activity has dropped again over the past 24 hours, with six C flares over the past day (11 UTC yesterday to 11 UTC today). The largest was a C2.7 from AR3500 at 12:52 UTC on November 26. The sun still has an impressive number of active regions – 12 in all – but most stayed the same or decayed some. Region AR3500 has maintained its beta-gamma-delta configuration, but its size and flare activity are small. AR3499 has developed a beta-gamma configuration, showing some increase in magnetic complexity.
The sun in recent days







Sun images from our community
We invite you all to send us your beautiful recent photos of sunspots and auroras. Naturally, we love receiving your photos! And to those of you who’ve already posted a photo to our community page, thank you.




Bottom line: Sun activity for December 4 is calm but we are waiting on the sun’s wind from a giant coronal hole to blast Earth providing more auroral displays.