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A/2017 U1 (previously C/2017 U1 (PANSTARRS)) is an apparently interstellar object passing through the Solar System. It was discovered on an extremely hyperbolic orbit by Robert Weryk on October 19, 2017[5] by the Pan-STARRS telescope, when the object was 0.2 AU (30,000,000 km; 19,000,000 mi) from Earth. Initially thought to be a comet, it was reclassified as an asteroid a week later.