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Sigmoids are a type of active region that has an 'S' (or 'reversed-S') shape because of their bending or twisted magnetic field structures. Since such distorted structures are unstable, sigmoids often erupt and sometimes become a source of big flares and coronal mass ejections (CMEs).
Although there are days and weeks when sigmoids are rarely seen, they sometimes appear in herds and adorn the solar disk. Early January of 2014 was such a period. We observed at least 6 different sigmoids in the first 15 days of the month. Below is information on each sigmoid appearing in the image above: