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 sits far out in the Solar System, small and dim, moving at a pace that barely fits human timelines. It was found in ...

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 ...

Pluto, discovered in 1930, was once considered the ninth planet in our solar system. In 2006, the International Astronomical Union reclassified Pluto as a dwarf planet because it doesn't meet all the ...

When NASA's New Horizons spacecraft sped by Pluto in 2015, it revealed an incredible world of ice and haze carved by various geological processes — hinting that an ocean may have played a role in the ...

Scientists have detected methane gas glowing faintly above Makemake, an icy dwarf planet smaller and farther than Pluto in space. Until now, Pluto was the only object that far out in the solar system ...

When the International Astronomical Union announced in 2006 that Pluto was being demoted from its status as the Sun’s ninth planet, many astronomers and non-experts alike were shocked. Pluto remains ...

On January 5, 2005, astronomers at NASA discovered Eris, the second-largest dwarf planet in the solar system. Eris is just ...

Lowell Observatory's sixth annual "I Heart Pluto Festival" will honor the remote icy world that was reclassified as a dwarf planet in 2006 When you purchase through links on our site, we may earn an ...