tau Cet is a Sun-like G-type star (about 0.78 solar masses, 5,310 K), 12 light-years from Earth. Tau Ceti is the nearest single Sun-like star, and its compact planets have made it a long-standing nearby-world target. tau Cet g is a 1.8-Earth-mass planet, with an orbital period of 20.0 days, at 0.133 AU from its star, on an eccentric orbit (e ≈ 0.06), discovered in 2017 via radial velocity. tau Cet h is a 1.8-Earth-mass planet, with an orbital period of 49.4 days, at 0.243 AU from its star, on an eccentric orbit (e ≈ 0.23), discovered in 2017 via radial velocity. Mutual gravitational tugs between the planets can slowly reshape their orbits, preserving clues to the system's assembly.