A winning and moderately easy concert piece that takes its name from one of the moons of Jupiter, Callisto is a vibrantly scored set of two variations on a fragment of a theme from the Jupiter movement of Gustav Holst's orchestral suite, The Planets. The characteristic flatted-7th of much English folk music is retained in both the quick opening section and the slow, reflective variation that forms the B section of this clever and appealing overture-style piece.