Richard Canfield and David McKenzie from Montana State University in the US, and Hugh Hudson from the Solar Physics Research Corporation in Japan, analysed two years worth of images from the X-ray satellite Yohkoh. In addition to the link between sigmoids and solar flares, they also confirmed that there was a link between solar flares and sunspot activity.

Several explosions take place on the Sun's surface every day but only a few point in the direction of the Earth. Previously, the only advance warning about the flares came from the SOHO satellite. However, SOHO could only give a few hours warning at most. The statistical relationship between sigmoids and solar flares can provide warnings days in advance.