Answer
Prior to Clyde Tombaugh's discovery of Pluto in 1930, no other known Kuiper belt objects had been identified or confirmed. Pluto, initially classified as the ninth planet, was later reclassified as a dwarf planet in 2006. Further exploration and observations using advanced telescopes have since led to the discovery of numerous other icy bodies within the Kuiper belt region, providing insights into the composition and formation of our solar system.