A device is described which produces and launches solid hydrogen pellets in a vacuum, for use in laser irradiation experiments. The pellets have both length and diameter of 0·25 mm, contain approximately 4×10 17 atoms, and are ejected with a velocity of 103 cm s -1. Most of the trajectories lie within 30 mrad of the mean. The device operates automatically and launches one pellet every 15 s.