Within decades, solar storms are likely to become more disruptive to planes and spacecraft, say researchers at Reading University. The work, published in Geophysical Research Letters, predicts that once the Sun shifts towards an era of lower solar activity, more hazardous radiation will reach Earth. The team says the Sun is currently at a grand solar maximum. This phase began in the 1920s - and has lasted throughout the space age. Mike Lockwood, professor of space environment physics at Reading, said: All the evidence suggests that the Sun will shortly exit from a grand solar maximum that has persisted since before the start of the space age. In a grand solar maximum, the peaks of the 11-year sunspot cycle are larger and the average number of solar flares and associated events such as coronal mass ejections are greater. On the other hand in a grand solar minimum there are almost no sunspots for several decades. The last time this happened was during the Maunder Minimum, between about 1650 and 1700. NG