Made in Finland, the X-ray Flux Monitor was launched aboard the Sunstorm CubeSat – about the size of a big, thick, paperback book – by Europe’s Vega rocket in August last year.

This stripped-down version of the full-scale XFM instrument, formally known as XFM-CS, has since amassed more than a year’s worth of data, observing hundreds of X-ray flares, dozens of them being associated with the occurrence of coronal mass ejections (CMEs). CMEs are huge explosions involving ejections of up to a billion tons of coronal plasma from the Sun at a time, which intensify the solar wind and are leading drivers of space weather.