From the time of its discovery in 1930 until 1992, Pluto was a happy, full-fledged planet. A little odd maybe with its tipped, eccentric orbit and tiny size, but the ninth planet just the same. That ...

Pluto hasn't been a planet for almost 20 years. In the early 2000s, scientists discovered several objects of a similar size to Pluto. So, during the summer of 2006, members of the International ...

For almost a decade, astronomers have been searching for a ninth planet in the solar system. Recently, new evidence of ...

Pluto's unusual eccentricity and tilt is likely due to its interactions with neighboring Neptune and other giant planets, ...

Scientists who argue for Pluto to be classified as a planet are getting more ammo for a debate that has raged over the last 15 years. A team of researchers published a study in the scientific journal ...

Astronomers are investigating a potential hidden planet, dubbed Planet Y, far beyond Neptune. Its gravitational pull is ...

Claims that the Solar System has a tenth planet are bolstered by the finding by a group led by Bonn astrophysicists that this alleged planet, announced last summer and tentatively named 2003 UB313, is ...

Demoted planet Pluto may have an ice volcano on its surface the size of Yellowstone, scientists recently discovered. The newly discovered volcano, Kiladze Caldera, was originally pegged as a crater ...

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