kepler's third law: a law stating that the ratio of the square of the revolutionary period (in years) to the cube of the orbital axis (in astronomical units) is the same for all planets
kepler's law: (astronomy) one of three empirical laws of planetary motion stated by Johannes Kepler
survivor guilt: a deep feeling of guilt often experienced by those who have survived some catastrophe that took the lives of many others; derives in part from a feeling that they did not do enough to save the others who perished and in part from feelings of being unworthy relative to those who died