Scientists now think they can explain why the hypervelocity stars - that's stars going at 600 - 1000 km per second are only spotted in one part of the sky, in the constellation of Leo, and it's down to their explosive origins. Douglas Boubert is a second year PhD student in the University of Cambridge, and he and his team used a computer model to try and work out what was going on. Georgia Mills heard what they found. Like this podcast? Please help us by supporting the Naked Scientists