At 1:09 PM ET (1709 GMT) on Tuesday, June 20, our star experienced an X-Flash, the strongest type of solar flare. Images of the flare were captured by NASA’s Solar Dynamics Observatory, which continuously monitors solar activity with satellites from other agencies and observatories of the European Space Agency, among other organizations.

“Solar flares are powerful bursts of radiation,” says NASA’s solar flare Twitter account. “Harmful radiation from glare cannot pass through Earth’s atmosphere to physically affect people on the ground. But if it’s dense enough, it can disrupt the atmosphere in the layer where GPS and communication signals propagate.”

The flare was associated with a coronal mass ejection (CME), a large cloud of superheated plasma ejected into space by the sun. According to SpaceWeather.com, which is quoting a NASA model, the CME did not target Earth and therefore will not develop any aurora here.

But solar plasma could trigger a bright light show on Mars that will be seen by orbiters such as NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) in a matter of days.

The sun is now approaching the zenith of its 11-year cycle of activity and many sunspots are accumulating on its surface. Sunspots, which are foci of magnetic activity, serve as launchpads for flares and CMES.

Usually these eruptions are harmless to humanity, only causing light shows. But NASA and other agencies are keeping an eye out for the sun in case a warning is needed to protect critical infrastructure like power lines or satellites. Source