According to both NOAA and Wikipedia, an X1 Class solar flare produces 0.0001 watts of energy per square meter, or greater. Therefore, an X45 solar flare would produce 0.0045 watts of energy per square meter. However, that cannot be correct. That is too absurdly small. http://www.spaceweatherlive.com/en/help/the-classification-of-solar-flares [Broken][/URL] Solar flare - Wikipedia, the free encyclopedia If a logarithmic scale is used, where: X1 = 0.0001 watts/m^2; X2 = 0.0002 watts/m^2; X3 = 0.0004 watts/m^2; X4 = 0.0008 watts/m^2; ... X42 = 219,902,325.5552 watts/m^2; X43 = 439,804,651.1104 watts/m^2; X44 = 879,609,302.2208 watts/m^2; X45 = 1,759,218,604.4416 watts/m^2. That does not appear to be correct either. That is too absurdly large. Outside of Earth's atmosphere the sun normally produces ~1,300 watts of energy per square meter. However, the atmosphere of the planet absorbs some of this energy and by the time the sunlight reaches the surface of the planet it produces ~1,000 watts of energy per square meter. I cannot figure out this solar flare classification scheme. In order to cause an aurora, much less having the ionized particles reach he surface of the planet, there must be considerably more energy than 1,300 watts per square meter hitting the planet. The article below is what got me thinking about the amount of power involved in solar flares: If the solar flare classification scheme uses a logarithmic scale, then a solar flare that is 10,000 times more powerful that an X45 solar flare would be producing 17.6 trillion watts of energy per square meter (the equivalent of 17.6 trillion Joules per second). Is that even possible, or am I way out in left field? Hopefully, someone can clear up my obvious confusion.