Pluto's days, though they drag on a bit at around 153 hours, are nothing compared to its years. Pluto's orbit takes 248 Earth ...

Earth has a newly-discovered neighbor in the solar system. But the heavenly body – possibly a dwarf planet à la Pluto – isn't a frequent visitor. Located beyond Neptune, its extreme orbit ...

Pluto, once considered the ninth planet, was reclassified as a dwarf planet in 2006 because it shares its orbital path with ...

Space probe isn't done after historic Pluto flyby. — -- New Horizons conserved energy by taking naps on its 3 billion mile journey to Pluto but the spacecraft isn't done yet and may have enough ...

Pluto’s thin, blue haze glows in this image from NASA’s New Horizons spacecraft. Though the dwarf planet is just a faint speck through a telescope, opposition this month offers skywatchers their best ...