Astro Watch : Scientists observing a curious neutron star in a binary system known as the 'Rapid Burster' may have solved a forty-year-old mystery surrounding its puzzling X-ray bursts. They discovered that its magnetic field creates a gap around the star, largely preventing it from feeding on matter from its stellar companion. Gas builds up until, under certain conditions, it hits the neutron star all at once, producing intense flashes of X-rays. The discovery was made with space telescopes including ESA's XMM-Newton.Discovered in the 1970s, the Rapid Burster is a binary system comprising a low-mass star in its prime and a neutron star – the compact remnant of a massive star's demise. In such a stellar pair, the gravitational pull of the dense remnant strips the other star of some of its gas; the gas forms an accretion disc and spirals towards the neutron star.As a result of this accretion process, most neutron star binaries continuously release large amounts of X-rays, which are punctuated by additional X-ray flashes every few hours or days. Scientists can account for these 'type-I' bursts, in terms of nuclear reactions that are ignited in the inflowing gas – mainly hydrogen – when it accumulates on the neutron star's ...