Starsees, also called sailseeds, are a fictional life form in the Known Space science fiction series by Larry Niven. These large (approximately one mile in diameter) "seeds" travel through interstellar space. Nothing is really known about them, other than they seem to migrate from the galactic center to the rim to eject their eggs, and then travel back to the core. Sometimes the eggs are ejected towards other galaxies, but most are left to hatch and migrate themselves to the core.