Assertion: asteroid belt's object | /r/CapableOf | begin in 1990
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text: After many more Pluto-sized and smaller icy objects were found orbiting beyond Neptune beginning in the 1990s, astronomers recognized that Pluto, far from being unique in its part of the solar system, is almost undoubtedly one of the larger and nearer pieces of this debris, known collectively as the Kuiper belt, that is left over from the formation of the planets.