Eight years after being reduced to a "dwarf planet" by the International Astronomical Union in 2006, our far distant cousin is finally getting some real push to be upgraded back to the ninth "planet" ...

Pluto is a bit of a loner. The dwarf planet is no longer considered a regular planet; it does not orbit on the same plane as ...

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 ...

A new study suggests yet another theory for a possible extra planet in our solar system, likely of a size between Mercury and Earth. The authors dubbed it Planet Y.

Using Pluto as an example, this celestial body, once considered the ninth planet, was redefined as a dwarf planet in 2006.

By Will Dunham WASHINGTON (Reuters) -Astronomers using the Hubble Space Telescope have observed a white dwarf - a highly ...

New observations suggest that the dwarf planet Makemake is surrounded by faintly glowing methane gas. Scientists are unsure ...

More than 50 times further from the Sun than Earth, the tiny dwarf planet Makemake is one of the last places you'd expect to ...