Peter Goldreich is renowned for his many collaborative insights into astrophysical topics as diverse as planetary rotation, pulsars, and helioseismology — the science of ‘sunquakes’. He correctly predicted that ‘shepherd’ moons maintain Saturn’s F ring. Peter’s research on the evolution and migration of planets is particularly important considering that over 1,000 planetary systems have already been discovered around stars other than the Sun.
Peter is an expert in the theory of resonances — the mathematics underlying the periodic reinforcement of the gravitational forces of two or more bodies orbiting a larger one. As well as Saturn’s rings, the theory helps to explain galactic spiral arms and ‘hot jupiters’ — Jupiter-like planets found very close to the star that they orbit.