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 ...

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

Pluto, a celestial snowball with a surface of methane ice some 3.6 billion miles from the sun, might be making its way back into the solar system fraternity. First discovered and classified as planet ...

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 ...

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