The sun emitted a significant solar flare on June 10, 2014. NASA’s Solar Dynamics Observatory - which typically observes the entire sun 24 hours a day — captured images of the flare.
This flare is classified as an X2.2 flare. 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.
About one hour later, the sun released a second X-class flare. This is classified as an X1.5 flare.