Powerful solar flare erupts from sun triggering radio blackouts across North America (video)

satellite view of the sun erupting with the M8.46 class solar flare. There is an insert on the right of the image showing a close up view of the flaring region. — Sunspot region 4114 erupted with a colossal M8.46 class solar flare on June 15. (Image credit: NASA SDO imagery, annotations added in Canva by Daisy Dobrijevic.)

An Earth-facing sunspot has turned into a prolific flare factory, firing off multiple powerful M-class solar flares in less than 24 hours, along with several minor C-class eruptions.

The most intense of these solar flares erupted on June 15, peaking at 2:25 p.m. EDT (1825 GMT) and registering as an M8.46-class — just shy of the X-class category, the most powerful type of solar flare. This eruption also unleashed a coronal mass ejection (CME) — a massive plume of solar plasma and magnetic field — now partially headed toward Earth. Forecasts suggest the CME's flank could strike on June 18, according to Spaceweather.com.

What are solar flares?

Solar flares are caused when magnetic energy builds up in the sun's atmosphere and is released in an intense burst of electromagnetic radiation.

They are categorized by size into lettered groups according to strength:

X-class: The strongest
M-class: 10 times weaker than X
C, B and A-class: Progressively weaker, with A-class flares typically having no noticeable effect on Earth.

Within each class, a numerical value indicates the flare's relative strength. The June 15 flare came in at M8.46, making it a near X-class event.

Radio blackouts across North America

map showing radio blackout across north america shortly after the M class solar flare eruption on June 15. — Short wave radio blackouts across North America. (Image credit: NOAA Space Weather Prediction Center)

Because flare radiation travels at light speed, it hits Earth in just over eight minutes. When it arrives, it ionizes the upper atmosphere (specifically the thermosphere), which can disrupt shortwave radio communication on the sunlit side of the planet.

During the M8.46 event, North America was directly facing the sun, making it the prime target for the resulting shortwave radio blackouts.

What's next?

The sunspot region behind this activity isn’t slowing down. It unleashed another M6.4 flare early on June 16 at 5:30 a.m. EDT (0930 GMT) and remains in an Earth-facing position.

More solar flares — and possibly more CMEs — could erupt in the coming days. If they do, we may be treated to more northern lights displays as our planet remains in the strike zone of this highly active region.

Keep up to date with the latest aurora forecasts with our aurora forecast live blog and for the latest geomagnetic activity breakdown, check out NOAA's 3-day forecast.

Daisy Dobrijevic joined Space.com in February 2022, having previously worked as a staff writer for All About Space magazine. She completed an editorial internship with BBC Sky at Night Magazine and worked at the National Space Centre, communicating space science to the public.

Daisy holds a PhD in plant physiology and a Master's in Environmental Science. Based in Nottingham, U.K., she covers all things space, with a special focus on solar activity and space weather. She also has a keen interest in astrotourism and is always on the lookout for the next northern lights adventure.

She will be a guest speaker aboard HX's Solar Eclipse Expedition in August 2026 and will join Hurtigruten as an onboard astronomer for a northern lights sailing in January 2027.