The sun emitted its fourth significant solar flare, peaking at 5:40pm EDT on Friday. This flare is classified as an X3.1-class flare.
NASA's Solar Dynamics Observatory, which watches the sun constantly, captured images of the event.
An X3.2-class flare erupted from the lower half of the sun on Oct. 24, 2014. This image of the flare was captured by NASA's SDO and it shows extreme ultraviolet light in the 304 Angstrom wavelength
X-class denotes the most intense flares, while the number provides more information about its strength. An X2 is twice as intense as an X1, an X3 is three times as intense, etc.
The flare erupted from a particularly large active region -- labeled AR 12192 -- on the sun that is the largest in 24 years. This is the fourth substantial flare from this active region since October 19.
Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel.