The hottest catalog of the year: the most comprehensive list of slow-building solar flares yet

Solar flares occur when magnetic energy builds up in the sun's atmosphere and is released as electromagnetic radiation. Lasting anywhere from a few minutes to a few hours, flares usually reach temperatures around 10 million degrees Kelvin. Because of their intense electromagnetic energy, solar flares can cause disruptions in radio communications, Earth-orbiting satellites and even result in blackouts.