Scientists using the European space agency (ESA) SOHO instrument have recorded four powerful solar flares that occurred within the space of just eight days. Solar flares are large explosions in the atmosphere of the sun, with the most powerful releasing energy equivalent to a thousand million mega tonnes of high explosive. Solar astronomers keep a close eye on solar flares as they can disrupt high technology systems. Space scientists used ESA's SOHO (Solar and heliospheric observatory) instrument to obtain advance warning of the events even though they were brewing on the far side of the Sun. Although SOHO cannot observe the region directly, it can form an image of activities in far side regions by analysing ripples on the Sun's surface. 'It adds some fun to see things coming,' commented Dr Philip Scherrer, a scientist from Stanford University, USA, who is involved in the project. SOHO is a cooperative project between ESA and NASA. The spacecraft was built in Europe for ESA and equipped with instruments by teams of scientists in Europe and the USA.