Pluto's unusual eccentricity and tilt is likely due to its interactions with neighboring Neptune and other giant planets, said Renu Malhotra, a planetary scientist at the University of Arizona who has ...

A new study suggests yet another theory for a possible extra planet in our solar system, likely of a size between Mercury and ...

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 recent study introduces the idea of Planet Y, a theoretical world that could explain strange gravitational behavior beyond ...

Astronomers using the Hubble Space Telescope have observed a white dwarf – a highly compact stellar ember – that appears to have gobbled up an icy world akin to the dwarf planet Pluto, a finding with ...

Exoplanet hunters Christopher Watson and Annelies Mortier explain the long search for a 'twin Earth' capable of sustaining ...

Earth is the only planet in our solar system with a single moon, making it a rare phenomenon for a planet of its kind.

In 2006, updated research led to Pluto being controversially demoted to dwarf planet status by the International Astronomical Union. The reasoning was that Pluto's location in the far-flung ...

Using Pluto as an example, this celestial body, once considered the ninth planet, was redefined as a dwarf planet in 2006. Its average distance from the Sun is about 5.9 billion kilometers, a distance ...

Full Video- http://www.youtube.com/watch?v=WHNO079G1i8 Pluto, Eris, and the Dwarf Planets of the Outer Solar System Exploring Space Lecture webcast live on Tuesday ...