Solar flare formation, illustration. Solar flares are eruptions in the solar atmosphere that cause a large increase in levels of dangerous radiation and charged particles. Solar flares also severely disrupt communications via satellite and radio. At left, gas rising from the Sun's surface is trapped by the Sun's magnetic field. Magnetic field lines (purple) converge at cooler regions on the Sun's surface known as sunspots. At centre, the magnetic field is expanding outwards, with a 'pinch' developing closer to the surface. At right, the outer part of the magnetic field breaks open as material escapes in the form of a flare. At the pinch point where the magnetic field lines cross and realign, there is a burst of energy (white glow) with associated expanding superhot gas (white).