Dark comets, mysterious objects with traits of both asteroids and comets, may have brought water to Earth in the past. An international team of astronomers, publishing in Icarus, suggests these dark comets could make up 60% of near-Earth objects and likely originated from the asteroid belt between Mars and Jupiter. Unlike typical comets, dark comets contain some ice but lack the visible dust and gas cloud. This discovery offers a new mechanism for ice delivery to the inner solar system.