Solar flare today: is the Sun active right now?
·Live data check: September 11, 2026, 09:36 UTC. Source: NOAA GOES X-ray flux. This block is rewritten every morning.
Yes. The strongest flare of the past 24 hours was a C1.6, peaking at 17:12 UTC on September 10, 2026, a small one, the routine kind. Over the past 7 days the Sun produced 0 X-class, 1 M-class, and 21 C-class flares; the strongest was an M1.0 on September 5, 2026.
The Sun flares nearly every day. What matters is the class: a C-class flare that nobody felt, or an X-class flare that faded shortwave radio across the daylit half of the planet. The line above answers that each morning from NOAA's GOES record, and the dashboard carries the live NOAA Kp and NASA's event list.
How do you check if there is a flare right now?
Open the Lumara dashboard and look at the space weather strip. It lists the latest solar flare from NASA's DONKI catalog with its class, so a glance tells you whether the Sun is quiet or active. Next to it you get recent coronal mass ejections and the live NOAA Kp index, the chain that reaches Earth. No login, no ads, and the sources are the same NOAA and NASA feeds forecasters watch.
What do the B, C, M, and X classes mean?
Flares are graded by peak X-ray output, and the scale is multiplicative. Each letter is ten times stronger than the one before it, so an X1 is a hundred times the energy of a C1.
| Class | What it means on Earth |
|---|---|
| B | Background level. No effect at the ground. |
| C | Small. Common, and usually unnoticed. |
| M | Medium. A brief fade of shortwave (HF) radio on the sunlit side of Earth, NOAA R1 to R2. |
| X | Strongest. Can black out shortwave radio across the daylit side of Earth, and paired with an eruption, can light up aurora far from the poles. |
Where can you see the flare on the Sun?
A flare is a burst of radiation from a magnetically tangled region on the Sun, and it shows up best in specific wavelengths. The 131 and 94 angstrom channels are tuned to the millions-of-degrees plasma that lights up during a flare, which is why those views look nearly black on a calm day and then flash bright when a region erupts. Lumara streams all twelve NASA wavelengths, so on an active day you can watch the spot that produced the number. The live NASA Sun image guide breaks down what each channel reveals.
Can a solar flare affect radio, GPS, or the internet?
The flare itself is light, so it arrives in eight minutes and the atmosphere absorbs it long before it reaches you. The knock-on effects are what matter. Strong flares ionize the upper atmosphere and disrupt the high-frequency radio that pilots and ham operators rely on. They can nudge GPS accuracy. And the big ones often travel with a coronal mass ejection, a slower cloud of plasma that takes a day or two to cross to Earth and can trigger the geomagnetic storms that drive the northern lights.
The last total solar eclipse crossed Iceland and northern Spain on August 12, 2026 (the record). The next one is August 2, 2027 over Egypt (the guide).
Common questions.
Is there a solar flare today?
Almost certainly a small one. The Sun produces low-level C-class flares most days. What changes day to day is the size. The line at the top of this page comes from NOAA's GOES X-ray record each morning, and the dashboard lists NASA DONKI's flare events with their class, so you can see at a glance whether today is quiet or active.
What do the solar flare classes B, C, M, and X mean?
They rank a flare by its peak X-ray brightness, and each step is ten times stronger than the one below. B and C are minor and harmless at the ground. M can fade shortwave radio on the sunlit side for a few minutes. X is the strongest and can black out shortwave radio across the daylit side of Earth.
Can a solar flare affect me on the ground?
Earth's atmosphere absorbs the radiation, so a flare is not a health risk on the ground. Large flares can disrupt shortwave radio, GPS accuracy, and satellites, and the eruptions that often come with them can push aurora to lower latitudes a day or two later.
Where does Lumara get its solar flare data?
The daily numbers on this page come from NOAA's GOES X-ray flux record. The dashboard lists flare events from NASA's DONKI catalog, which posts them a few hours after they happen. Both are free in Lumara with no account and no tracking.