Sun-like stars produce superflares roughly once per century

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By Valeriy Vasilyev et al, Science. 

Editor's Summary: Solar flares are bright, transient, multiwavelength emissions from active regions on the Sun. The most intense directly observed solar flares release energies of about 1032 erg. It is unclear whether the Sun can produce more intense flares than that or how often they might occur. Vasilyev et al. investigated brightness measurements of 56,000 Sun-like stars observed by the Kepler space telescope. They identified almost 3000 bright stellar flares with energies of about 1034 to 1035 erg, which are called superflares. The occurrence rate is about one superflare per star per century. If the Sun behaves like the stars in this sample, then it could produce superflares at a similar rate. —Keith T. Smith. 

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