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because it was named for the Roman god of the underworld |
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although the “New Horizons” spacecraft made a voyage there and beyond in 2006 |
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when the International Astronomical Union (IAU) changed its status to that of dwarf planet |
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as it is very difficult for astronomers to collect reliable information about it |
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while Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune are “classical” planets |