The magnetic classification is associated with solar flares—thankfully they're unlikely to be disruptive.
The flare itself wasn't disruptive, but it indicates that a source of more flares could be slowly rotating toward our planet, according to officials.
Cosmic rays recorded in the atmosphere above California have dropped sharply thanks to the sun's increasing activity.
A huge "full-halo" solar ejection is headed straight for Earth, and will result in spectacular auroral displays on July 23.
A surge of solar wind following a coronal mass ejection from the sun is due to hit the Earth's atmosphere, creating a beautiful aurora display.
Streams of solar particles can force satellites out of their orbits. Over the next few years, it's a problem that could only get worse.
In 1859, a solar flare shocked the world. In 2012, we had a very close miss. At some point, Earth will be hit again.
Data is unclear as to whether the coronal mass ejection is facing away from or towards Earth—though it's unlikely to cause disruption either way.
The huge sunspot has the potential to send a solar flare our way. Whether it will or not remains to be seen.
A solar storm as large as four planet Earths has been recorded hovering above the Sun's surface.
Fortunately the M-class solar flare was not strong enough to be disruptive for us on Earth, though its bright flash was clear to see for NASA cameras.
A region of the sun that has only just rotated into view was responsible for a huge solar flare earlier this week associated with a radio blackout warning.
When a solar flare knocked out radio communications during the Cold War, disaster was narrowly averted. Experts discuss how likely this scenario is today.
The group of dark blots on the sun's surface are areas of intense solar activity that could flare towards our planet.
The flare erupted from the sun on Wednesday night, and scientists are working to determine if a coronal mass ejection (CME) is headed towards us as a result.
The number of sunspots—areas where solar flares and charged particles may erupt from—appears to be ahead of forecasts.
The stunning phenomenon, also known as aurora borealis, could be seen in states including South Dakota and Montana on Wednesday night as part of a geomagnetic storm.
Two solar eruptions are heading towards Earth and could hit us by Thursday, said the Space Weather Prediction Center.
The energy, known as a coronal mass ejection (CME), erupted from the sun's surface on March 7 and might deliver a glancing blow to our planet.
Had the explosion occurred today, it would have been "catastrophic" for satellites, aircraft, and computers, said scientists.
The storm, caused by a huge release of energy from the sun in the form of a coronal mass ejection, might also interfere with some electronics.
The burst of solar energy erupted from the sun on Thursday morning and was strong enough to potentially disrupt radio communications.
Santa will have some extra illumination to guide him over the North Pole this year as charged particles from the sun potentially enhance the aurora borealis.
The colorful auroras showed up from Scotland to Canada after scientists warned of potentially disruptive events following the space-based phenomenon.
The flare was facing away from Earth at the time it was recorded, but soon our planet could be looking "right down the beam" of solar activity.
It comes just weeks after scientists warned that a solar storm could set off voltage alarms and cause radio disruption.
The storm caused auroras as bright as day and widespread communications disruptions back in 1859.
Solar storms have the potential to knock out power systems, and some warnings have been issued because of this burst of activity.
Scientists announced the start of Solar Cycle 25, signaling the end of the solar minimum, on September 15.