Watch a ball throw on each planet in our solar system, plus Pluto and the moon, below. Imagine throwing a baseball. Easy, right? Maybe you've already done it a few times. Now imagine throwing a ...

Pluto has long been one of the most debated celestial bodies in our solar system. Once classified as the ninth planet, it was redefined in 2006 as a dwarf planet, a decision that still sparks ...

All planetary systems have this point, called a barycenter, where their mass is perfectly balanced. For some systems - like Pluto and its moon, Charon - the barycenter is outside the planet. See more ...

We discovered something: Pluto was different! Pluto was discovered because Neptune’s orbit showed an anomaly that indicated that there was something else out there. So they looked and eventually Clyde ...

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 many people, the definition of a planet was only made clear in 2006, when the spunky world Pluto was demoted from a planet to a dwarf planet. Now, a team of astronomers is pushing for “planet” ...

“My very excellent mother just served us nine.” It doesn’t quite work without “pizzas” at the end. Nor do other schoolchild mnemonics for remembering the planets of the solar system, now that Pluto ...

Once the quirky underdog of our solar system, Pluto held planetary status until 2006, when it got a cosmic demotion that still stings space fans. Discovered in 1930, Pluto was the ninth planet for ...

Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto. Many Americans grew up with this as the definitive planetary lineup and created clever mnemonic devices to memorize them in ...