Superflares (white area) arise from starspots (dark areas) much larger than those seen on our Sun.Hiroyuki Maehara (Kwasan and Hida Observatories, Graduate School of Science, Kyoto University) Some middle-aged stars burn and rave like newborns, producing flares thousands of times as energetic as those we see on the Sun, according to the first large survey of these events.Solar flares occur when magnetic-field loops threading through sunspots get twisted and break, releasing massive amounts of radiation and accelerating charged particles into space. The largest ever measured on the Sun took place on 1 September 1859, and was observed as a...