SNAP-1 is a tiny spacecraft weighing only six kilos. Constructed by engineers at Surrey University, it is the latest in a line of nanosatellites which are set to have a dramatic impact on our ability to explore and utilise space. Quentin Coopertalks to Dr Craig U nderwood and Dr Andrew Coates about the engineering of these machines and the future of nanosatellite technology. Producer John Watkins. E-MAIL: material.world@bbc.co.uk