KOI-351 is a Sun-like F-type star (about 1.20 solar masses, 6,080 K, 1.20 solar radii), 848 light-years from Earth. Kepler-90 (KOI-351) is the only known eight-planet exoplanet system, a packed architecture that matches the Solar System in planet count. The system hosts 8 confirmed planets on orbits ranging from 7.0 days to 332 days. With 8 confirmed worlds, KOI-351 is a densely packed system whose resonances, spacing, and formation history are active research topics. Mutual gravitational tugs between the planets can slowly reshape their orbits, preserving clues to the system's assembly. KOI-351 b orbits well inside Earth's distance from the Sun. At 1.3 Earth radii, KOI-351 b is a compact world comparable in size to rocky planets in our Solar System.